View Full Version : Neurochrome Modulus-686
After upgrading my speakers to some Triangle Esprit Antal EZ, I want a bit more power than my Modulus-86 or Firebottle Monos can provide.
As I like the sound of the Modulus -86 amplifiers I currently have, I have decided to build myself a Modulus-686.
This is my first DIY build, so to test my skill/capability I started with the Guardian 686 speaker protection module. This is something I completed during the 1st confinement here in France, but I did not get round to testing it. It is now tested, and as we head into a second confinement, I have decided to build the power supply boards.
The target is to build a dual mono version in a large case. For this, I need two power boards. They were ordered last week, and have already arrived. I am mot waiting for the parts to arrive from Mouser before I start building them.
This is going to be a long term build, to spread the cost out a little.
Firebottle
04-11-2020, 07:48
Funnily enough I am also building a 686 amplifier for someone. Shall I posts pics on here?
killie99
04-11-2020, 07:56
I’ve just completed my dual mono 686, well, when I say completed I mean it’s playing music but still some work to do on tidying it up. I’ll see if I can post a pic later to show the inside
Funnily enough I am also building a 686 amplifier for someone. Shall I posts pics on here?
Why not. It will give me an idea of what mine should look line.
Out of interest, what transformers are you guys using?
I was thinking 2 off 2x24v 400VA, but someone has suggested 600VA. Price difference is not great, so is it a good idea?
ianlenco
04-11-2020, 09:17
I had an email from Tom yesterday about the release of 686 Rev 1.1 - is this what you guys have got?
That is what I am going to get. I need to shift some gear before I place my order.
killie99
04-11-2020, 09:37
I used two 25V 400VA Audio Grade from Toroidy, if you get bigger VA make sure they fit in the case as I almost made that mistake. Mine is a fairly big case and there's not a lot of room left. Internal dimensions of my case are: Width= 330mm Height= 142 mm Depth = 300 mm
https://i.postimg.cc/hv5bmkKW/amp-top-smallish.jpg (https://postimg.cc/Mf1Q2rcd)
https://i.postimg.cc/0jQ0bkR0/amp2-rear-smallish.jpg (https://postimg.cc/TLzDsXPK)
I have been advised to use 2 x 24V to allow for higher voltage on the mains.
That looks like a tight fit. One of the reasons I am looking atba 4U or 5U 400mm deep case. I just need to make sure it fits in my rack first.
ianlenco
04-11-2020, 09:51
If anyone is after a case for their project I have this spare.
https://i.imgur.com/Nnszrwth.jpg#gWPQG
Great heatsinks :) If you are interested pm me and we can talk details.
I've been thinking about attempting a Neurochrome build. how difficult is it -- a matter of connecting cables following clear, easy to follow templates or something that requires specialist understanding of circuit diagrams etc?
killie99
04-11-2020, 16:15
It's pretty straightforward. Tom supplies very good instructions on how to put it all together.
You can buy the Mod-686 fully populated but the other boards (if you want to use them, there are others available) Power-686, Guardian and ISS need to be purchased as bare boards and you need to order parts and stuff the boards yourself. Again, Tom supplies you with the BOMs, which you can order from Mouser as a project, so it's pretty easy to get all the correct parts - or you can choose to purchase the components you require from anywhere.
You don't need to be able to understand circuit diagrams to build it but ability to solder and distinguish different types of components (how to correctly orientate diodes electrolytic capacitors etc) is fairly essential.
There is a new ISS (intelligent soft start( coming out soon, which is only available fully populated.
I was unsure if I could do this, hence building the Guardian 686 first. That went quite well, so now I plan to build the power boards.
Progress
https://live.staticflickr.com/65535/50573141147_1b7e3e0cfa_c_d.jpg
Guardian 686
https://live.staticflickr.com/65535/50573011351_9a1c9525a8_c_d.jpg
Power 686
https://live.staticflickr.com/65535/50573012656_721ddabdde_c_d.jpg
Power 686 from the other end.
2nd Power 686 finished.
https://live.staticflickr.com/65535/50573339727_ea951598fa_c_d.jpg
Probably total overkill, but I don't intend to use any other amplifiers after this is finished.
I've been thinking about attempting a Neurochrome build. how difficult is it -- a matter of connecting cables following clear, easy to follow templates or something that requires specialist understanding of circuit diagrams etc?
The Power 686 boards were easier than the Guardian 686 to build, in my opinion.
There is less space between components, and the transistors were a challenge, but I watched a few YouTube videos, and I succeeded at my first attempt.
If you can solder, and use the internet, it is relatively easy.
The instructions supplied are very clear. There are step by step photos of what your board should look like as you progress through the stages.
I think I have just finished the soldering for this project now, apart from maybe a few cables to make up the harnesses.
It was quite therapeutic.
killie99
06-11-2020, 16:35
Kevin, Looks like you've configured the Guardian incorrectly. To use the Guardian with a Mod-686 you must use the balanced/bridged/BTL configuration, see page 11 of Tom's Guardian guide and you need 2 Guardian's, one for the left channel and a Guardian for the right channel.
It's built for a dual mono.
hornucopia
06-11-2020, 17:05
What IS a Guardian circuit? Surge protection? Soft turn-on?
And kudos to Stuart for observation!
It's built for a dual mono.
But you may be right, I may need two for a 686. In which case it may well be configured incorrectly.
It looks like you are correct.
Thanks for pointing it out.
Time to order some more parts...
What IS a Guardian circuit? Surge protection? Soft turn-on?
And kudos to Stuart for observation!
A speaker protection circuit.
killie99
06-11-2020, 17:29
I only know because when I was ordering the boards from Tom he explained that regardless of the configuration, if you are using the 686 boards you must have a Guardian for each channel
killie99
06-11-2020, 17:49
One of the guys on DIYAudio did a great build guide:
https://blog.andytather.co.uk/index.php/lm3886-build-thread/
I only know because when I was ordering the boards from Tom he explained that regardless of the configuration, if you are using the 686 boards you must have a Guardian for each channel
Thanks. I have reconfigured the board. You have saved me some disappointment later in my build. :thumbsup:
https://live.staticflickr.com/65535/50572712263_3bc2d6e2b9_z_d.jpg
Time to order the missing one.
One of the guys on DIYAudio did a great build guide:
https://blog.andytather.co.uk/index.php/lm3886-build-thread/
I found that one. It looks very tight in a 300 mm case. I was thinking going for 400mm.
It is almost a shame to hide those transformers away as well...
What did you guys use for a soft start?
My Toroidy transformers have shipped (2 x 24V, 400VA) so I need to sort out a good soft start so I can test the Power 686 boards.
killie99
10-11-2020, 15:18
I used Tom's V1 ISS board - guess that isn't an option anymore as he's replacement it with a V2. Pretty much the same features though other than selectable soft start delay and emergency shutdown for Hypex and Purify boards.
hornucopia
10-11-2020, 16:44
A speaker protection circuit.
Must find out if my 86 has one! Firebottle.....?
Firebottle
10-11-2020, 17:40
No it doesn't but the 3886 power chip has a lot of built in protection.
What are you using as a soft start Alan?
Firebottle
10-11-2020, 21:07
The 286 I have is using the switch mode psu's (2x) with built in soft start.
The 686 build has the Neurochrome board.
A question about the case.
I am going to order a case from Modushop, the 4U/400 Dissipante.
I am just wondering how you specify the holes in the back panel? I have the CAD file, but how many holes do I need to pay for?
Did anybody get the case engraved/printed as well?
This weekend has seen me altering the CAD files that Tom makes available for my specific build.
I noticed that the distance between the hole centres was not correct for the Mod 686 V1.1, so I had to find a decent CAD package, learn how to use it, and produce the drawing file for Modushop to prepare my case.
28848
The first is the side view, with the positioning of the boards, with the holes drilled and tapped for me to fit the PCBs.
28849
Then we have the rear layout, to which I have deleted the trigger, and added RCA inputs as I want the option of both inputs.
WBT binding posts will be used, so the cutouts have been modified for them.
28850
Then we have my proposed layout, where I will be putting the power 686 boards up on a mezzanine floor.
killie99
17-11-2020, 17:36
20% off at Modushop from 20-30 Nov with code BLACKFDAY
I am still waiting for the ISS and Mod 686 boards, but thought I would progress with what I can.
So, I fitted the transformers, built the Mezzanine and fitted the Power 686 boards to it, and trial fitted it in the case, just to make sure I can get the top on.
https://live.staticflickr.com/65535/50681936118_49d549cb37_c_d.jpg
I am happy with the progress so far.
One thing that I have learnt this weekend is that the 19mm spacing of the binding posts limits the choice of posts.
If you are getting a dissipante case machined up, increase this to the 30mm standard, and you will have more choice of a quality post.
Not much progress has been made recently, as I am mainly waiting for parts.
I have fitted the binding posts, and I have connected the transformers to the Power 686 boards and check that they function correctly.
I am happy to report that they do.
Tomorrow should see my Intelligent Soft Start and Mod686 boards arrive, so I may be able to wire this up at the weekend.
Hi Kevin, just noticed this thread. I would like to make a suggestion regarding your binding posts. When I repurposed an ancient GAS Son of Ampzilla chassis to build a Neurochrome 286 I connected it up with the ubiquitous brass, nickel and gold speaker posts parading as 'connectors'. I used these to fire up the amp knowing that from experience I would later modify the connection.
This mod. consists of a pair of 8mm diameter cheapo binding posts chosen merely for strength, although stainless steel 316 nuts and bolts would allow more torque and be better. The posts or bolts are used merely as clamps and are not used to conduct the delicate audio signal.
I bring the cable directly from the Neurochrome modules outside the amp and terminate to a FUREZ pure unplated copper lug. The same make of lug on the speaker cable and the lug from the module is then placed back to back and clamped with as much force as you think it will stand. I took a spanner to my 8mm posts and torqued the hell out of them. This method does away with the great expense of quality binding posts and the usual terminals, and more importantly removes any possible deleterious effect of the binding posts.
I use the same principle to connect to my speakers. Obviously this is not appropriate for components that you may later wish to sell but I am happy to do it to my DIY stuff.
Short of soldering your speaker cables directly to the modules, which is not very practical, this is the next best thing. You have effectively removed the posts from the signal path. I modded a friends Aragon 4004 but at his urging retained the original binding posts. My old Hafler power amp also responded well to this.
BUT: does this really make a difference? Yes, it really does.
I have always had a soft spot for James Bongiorno's amps, the design genius behind Great American Sound but feel Tom's 286 is possibly better, certainly possesses a lower noise floor but is ruthlessly revealing. Good luck with your build.
hornucopia
18-12-2020, 20:40
....so, you thread the wire from amp board through the case hole, then add lug?
Keeping the wires insulated against touching the case, of course!
Having a Hafler DH200 makes me think.....(besides the 86 amp!)
Looks like DNMs idea of speaker pins is parallel here? Less metal in circuit.
Thanks for the info Charles.
I have already bought and fitted the speaker binding posts, but bought ones without masses of metal in them as a compromise.
I managed to do a bit more last night and this morning.
https://live.staticflickr.com/65535/50735273863_9ffaced4cb_c_d.jpg
When I ordered my case, I did not realise that the Intelligent Soft Start PCB had changed dimensions from the previous version, so I had a choice of drilling more holes in the case, or making a mounting plate.
I want for the plate, as it will give a cleaner external look.
I have connected up all of the power supply system to run a final check that everything is as it should be, prior to connecting up the amplifier power, and the input/output signal wiring.
So far, so good.
No magic smoke has escaped.
@hornucopia, Yes exactly. PM me if you have any questions so as to not derail this thread.
https://i.imgur.com/VmfvxFD.jpg
killie99
19-12-2020, 15:13
Kevin, what's the diameter of the holes in your case for the speaker terminals? I managed to track down some gold plated tellurium copper speaker posts at Mouser (548-BU-P3770-0) but they need a small 9.5mm hole but means no chunky brass nonsense in the signal path.
Stuart,
The right size for some gold plated, pure copper binding posts from Viborg. :thumbsup:
I just need to ground the XLR sockets to the chassis, and then I am done....
Power on has been achieved.
I had a couple of minor issues, but I have managed to resolve them.
Troubleshooting did involve removing the speaker protection, but it made no difference.
I will be adding the speaker protection back into the circuit tomorrow.
For the moment, I am just going to play some tunes, with a feeling of content.
https://live.staticflickr.com/65535/50739285248_f0ac8ba723_c_d.jpg
The last photo taken before I put the lid back on after tidying up the cabling.
Power on with the speaker protection in the circuit was achieved this morning.
It is sounding fabulous. I am very happy with my first build. It is going to take quite an amplifier to better this beast.
camtwister
20-12-2020, 14:31
I'm chuffed for you, Kevin.
I hope you get much enjoyment from your efforts.
ianlenco
20-12-2020, 14:54
Great stuff! As my first amplifier build a few years back I put together the original Modulus 86 - it was also my first effort with proper soldering. I learnt a lot about all the components needed and which way round to solder them :lol: I don't think I would have got anywhere without Tom's guidance. They sounded great too and I dare say the 686 sound even better.
Congratulations
Thanks guys.
There is something very satisfying about listening to an amp you built yourself.
i bet there is,well done k for getting stuck in!
killie99
20-12-2020, 19:33
Brilliant, glad it's all working as it should!
https://live.staticflickr.com/65535/50739285248_f0ac8ba723_c_d.jpg
The last photo taken before I put the lid back on after tidying up the cabling.
Power on with the speaker protection in the circuit was achieved this morning.
It is sounding fabulous. I am very happy with my first build. It is going to take quite an amplifier to better this beast.
Hi Kevin
Well done
I am contemplating the Modulus 86 build and have been in touch with Tom Christensen.
I gather you have 2 x Power 686 s in there in the middle of the chassis.
Silly me but where are the torroids ? Hope you will indulge this novice.
With my intended 86, I might opt for SMPS as Tom says the amp is PSU agnostic.
Would you have any comments about that, as I note from yr opening post that you also have the 86.
Ta.
The toroids are hiding beneath the power 686 mounting plate, which is raised above the bottom of the case.
The Mod-86 is a good amp, but my speakers needed a bit more power.
All my Mod-86 amps have had torroids, so I have no experience with an SMPS.
I have read that people have swapped from SMPS to toroidal and reported an improvement in sound quality.
Ah Thanks.
I dont need much power so i figure the 86 will be fine
Mines a semiactive drive of modded NS1000s, and also a pair of JBLs done a similar way
I need a nice sounding stereo power amp just to drive the High Pass to tweets and midranges via simple passive XOs
Which one of Tom's construction would you guys recommend when it comes to quality not power ?
MOD686 with lower supply voltage or something else ?
Thanks in advance for your advice.
I think they all share the same basic circuit design, so I would select the amp based on the power requirements.
I went from Mod -86 monos to a 686 as I wanted more power to control the speakers better.
The sound did not change much, if at all.
I thought so but started to doubt about it when I found Tom saying this :
"In my own unscientific listening tests I did find that the LXmini cleans up a bit at high volume levels when powered by the Modulus-286, compared to the Modulus-86. I did not perceive any difference between powering the LXmini with the Modulus-286 and the Modulus-686."
At high volume...
If you often listen at high volume, then it’s probably the most powerful amp that you want.
I've been thinking about attempting a Neurochrome build. how difficult is it -- a matter of connecting cables following clear, easy to follow templates or something that requires specialist understanding of circuit diagrams etc?
It is a straightforward assembly job, more mechanical than electrical I think. If you can wire a plug you can build one of these!
Just beware that the Neurochrome 686 is a very neutral amplifier with almost no character of its own other than it has a high level of clarity due to its low distortion chip amp design. So what you use with it will reveal there own character as it were.
It is a fantastic amplifier to hear but it has no character whatsover and reminds me of digital audio, processing music in a robotic way. Technically it is as good as it gets and very accurate.
However if you want to reveal truly what this amplifies abilities are and how it sounds listen to some vocals you know well. Yes they will sound very detailed and very clear but they will not sound like the person you probably know from your current system.
I know what the vocalists should sound like from my own system as I have heard them live and I can make the comparison.
The Neurochrome 686 made the same vocalist almost unrecognisable.
Opti-cal
19-02-2021, 09:32
It is a straightforward assembly job, more mechanical than electrical I think. If you can wire a plug you can build one of these!
Just beware that the Neurochrome 686 is a very neutral amplifier with almost no character of its own other than it has a high level of clarity due to its low distortion chip amp design. So what you use with it will reveal there own character as it were.
It is a fantastic amplifier to hear but it has no soul whatsover and reminds me of digital audio, processing music in a robotic way. Technically it is as good as it gets and very accurate.
However if you want to reveal truly what this amplifies abilities are and how it sounds listen to some vocals you know well. Yes they will sound very detailed and very clear but they will not sound like the person you probably know from your current system.
I know what the vocalists should sound like from my own system as I have heard them live and I can make the comparison.
The Neurochrome 686 made the same vocalist almost unrecognisable.
That's what preamps are for!
My 686 allows the upstream components and ancillaries to be heard, very clearly.
I don't think I would partner it with similarly 'neutral' preamps. That ultimate transparency can certainly be a bit too much at times. (I think this is what you're eluding to Jim??). I completely agree it is reminiscent of some Class D amps and does have a somewhat synthetic 'digital' sound. A little cold at times.
Hence why I will only ever partner it with something that adds a little 'flavour' or harmonics in the form of tubes. I certainly wouldn't try partnering it with a passive pre or indeed straight from a DAC's variable output etc.
BUT - with that added 'soul' (and possibly speakers slightly favoring the lower registers) it has magnificent heft, weight and grip on any music I put through it. It also does cue's and transients incredibly accurately and go from 0-100 like no other bit of kit I've heard. Soundstage pushes miles beyond the speaker boundaries without breaking sweat even a little. Drove Quad 63's (before one went bad ((unrelated)) on me) with stunning ease.
Cheers
That's what preamps are for!
My 686 allows the upstream components and ancillaries to be heard, very clearly.
I don't think I would partner it with similarly 'neutral' preamps. That ultimate transparency can certainly be a bit too much at times. (I think this is what you're eluding to Jim??). I completely agree it is reminiscent of some Class D amps and does have a somewhat synthetic 'digital' sound. A little cold at times.
Hence why I will only ever partner it with something that adds a little 'flavour' or harmonics in the form of tubes. I certainly wouldn't try partnering it with a passive pre or indeed straight from a DAC's variable output etc.
BUT - with that added 'soul' (and possibly speakers slightly favoring the lower registers) it has magnificent heft, weight and grip on any music I put through it. It also does cue's and transients incredibly accurately and go from 0-100 like no other bit of kit I've heard. Soundstage pushes miles beyond the speaker boundaries without breaking sweat even a little. Drove Quad 63's (before one went bad ((unrelated)) on me) with stunning ease.
Cheers
Great to hear you have incorporated the 686 and managed to give it a bit of soul by adding carefully chosen pieces of kit up and down stream. I think this is what is needed to get the best out of the 686.
cheers
Opti-cal
19-02-2021, 10:15
Great to hear you have incorporated the 686 and managed to give it a bit of soul by adding carefully chosen pieces of kit up and down stream. I think this is what is needed to get the best out of the 686.
cheers
Thanks Jim,
for anyone interested a fully tube rectified preamp (Musical Paradise MP-701) using Mullard GZ34, 6SN7 X4 (tried various RCA/Sylvania combos) eventually settled on some Russian 6H8C tubes (6SN7 equivalents) was exactly what was required to get the 686 beyond just being an incredibly powerful, neutral amplifier.
To be fair the preamp also has massive Audyn Copper and Mundorf Supreme Gold caps (probably a few hundred quids worth) and has been fettled by Mr Alan Firebottle so its at a very decent level of performance. If i do stick a merely 'decent' preamp in there I don't doubt a lot of the character I now have in the system would be removed with it.
Cheers
Firebottle
19-02-2021, 10:43
Cobblers you pair. Character? Soul?
What I have hear is absolute transparency and accuracy to what's in the recording.
If the vocalist doesn't sound the same as in real life that is down to how the recording was done. A concert hall is never going to sound the same as a studio.
Opti-cal
19-02-2021, 10:52
A concert hall is never going to sound the same as a studio.
Whilst I agree with you there if what you say is correct then I certainly prefer the added distortion/harmonics a concert hall (or in this case some tubes) adds. Right or wrong it just sounds better to these ears!
Listening to the 686 with a very transparent active pre, whilst undoubtedly accurate (to a fault in certain recordings), is never as much fun as listening with some tubes in the mix. System dependent of course . . . .
If accuracy is the sole goal then blessed be the 686 with an equally transparent pre however I'm still finding out exactly what I'm looking for . . . . think U2 did a song about that kind of thing . . .
Cobblers you pair. Character? Soul?
What I have hear is absolute transparency and accuracy to what's in the recording.
If the vocalist doesn't sound the same as in real life that is down to how the recording was done. A concert hall is never going to sound the same as a studio.
Thats your opinion Alan. From my experience the 686 was the most characterless amplifier I have ever heard and correct me if I am wrong but I though you said it had no character of its own on a post somewhere?
Whilst I agree with you there if what you say is correct then I certainly prefer the added distortion/harmonics a concert hall (or in this case some tubes) adds. Right or wrong it just sounds better to these ears!
Listening to the 686 with a very transparent active pre, whilst undoubtedly accurate (to a fault in certain recordings), is never as much fun as listening with some tubes in the mix. System dependent of course . . . .
If accuracy is the sole goal then blessed be the 686 with an equally transparent pre however I'm still finding out exactly what I'm looking for . . . . think U2 did a song about that kind of thing . . .
You have absolutely nailed what the 686 is about Chris and I agree if you want neutrality, transparency and accuracy this is the amplifier to buy.
Some of us want a different flavour or musical experience from our music not always exactly what the mastering engineer was listening too in the studio.
walpurgis
19-02-2021, 11:03
An amplifier is a tool. It is only required to 'make the signal bigger', if it does anything else like adding "soul" or "character" then there's something wrong with the design!
An amplifier is a tool. It is only required to 'make the signal bigger', if it does anything else like adding "soul" or "character" then there's something wrong with the design!
I agree with you there Geoff to a point but no two amplifier ever sound the same and certainly valve and solid state amplifiers will produce a different interpretation of the recording.
Its up to the individual to decide which is the most accurate and which one they enjoy most.
Thats your opinion Alan. From my experience the 686 was the most souless amplifier I have ever heard and correct me if I am wrong but I though you said it had no character of its own on a post somewhere?
You seem to contradict yourself, an excerpt from your "Jimblog":
"I was so impressed with the 686 performance in all the combinations I tried today. It has star quality and I feel it may well be exactly what I am looking for. Compared to other muscle amps I have heard it goes about its business without letting you know it is there, most other power amps I have heard have their own sonic signature. Not the 686. I know this amp was engineered for vanishingly low levels of distortion but I was anxious this would also mean it had no soul or spirit. This is certainly not the case.
The Croft although transparent is not as clean as the 686 or grain free so it must be introducing something else which becomes apparent when switching between the two. I wrote in my listening notes the words analogue, smooth and clarity many times. It is this very aspect that makes the 686 stand out above most amps I have heard. I have heard greater clarity from other power amps but they then become etched and fatiguing, not so the 686. You could listen to this in your system without ever tiring from it. As Alan ( Firebottle) said it almost has no sound of its own, you have to dial this in with your own ancillary equipment whether that is digital or analogue, valve or SS"
I agree with you there Geoff to a point but no two amplifier ever sound the same and certainly valve and solid state amplifiers will produce a different interpretation of the recording.
Its up to the individual to decide which is the most accurate and which one they enjoy most.
It is not up to you what amplifier is more "accurate", the specifications and circuit design do that. It is only for you to decide what amplifier you prefer listening to.
Opti-cal
19-02-2021, 11:16
From my relatively short experience . . . . .
Power amplifier - Neutral
Source/DAC - Neutral
Speakers - Neutral
Preamp - whatever you like - warm, lush, rich, revealing, transparent or indeed neutral etc.
It's where preferences and tweaks can be made most noticeably to the system. In an ideal scenario all of it would be 'neutral' (of no character) but our ears (senses) aren't all stimulated by the same things (objective sound).
Until I settled on the 'right' (for me) combination of tubes/caps etc for this particular preamp I had 3-4 other amplifiers around just in case and as a reference. Class A, tube, integrated, class D. With this preamp and this power amp they are all sold/for sale.
Room acoustics also play a part in this, a neutral amplifier (preamp/whatever) may sound way too harsh in a 'sharp' acoustic environment. Changing to a warmer/lusher sounding one (maybe rolled off/distorted) may be exactly what the room (and therefore in this case 'the system') requires. At least in the interests of listener satisfaction. At this point measurements and accuracy are a fallacy. They give you the information straight and true, if you don't actually like listening to this information (accurate or not) then there is no point in chasing it really is there?
Depends what you're in it for really.
Personally accuracy/transparency has gotten me very close to where I want to be (huge fan of Quad 57/63's) but had I been simply wanting to increase accuracy/transparency I certainly wouldn't have settled on this preamp. That would have been a mistake as far as my listener satisfaction is concerned.
You seem to contradict yourself, an excerpt from your "Jimblog":
"I was so impressed with the 686 performance in all the combinations I tried today. It has star quality and I feel it may well be exactly what I am looking for. Compared to other muscle amps I have heard it goes about its business without letting you know it is there, most other power amps I have heard have their own sonic signature. Not the 686. I know this amp was engineered for vanishingly low levels of distortion but I was anxious this would also mean it had no soul or spirit. This is certainly not the case.
The Croft although transparent is not as clean as the 686 or grain free so it must be introducing something else which becomes apparent when switching between the two. I wrote in my listening notes the words analogue, smooth and clarity many times. It is this very aspect that makes the 686 stand out above most amps I have heard. I have heard greater clarity from other power amps but they then become etched and fatiguing, not so the 686. You could listen to this in your system without ever tiring from it. As Alan ( Firebottle) said it almost has no sound of its own, you have to dial this in with your own ancillary equipment whether that is digital or analogue, valve or SS"
I stand to be corrected and after my final listening session I believed the 686 had no soul but it certainly had spirit, a very neutral one.
It is not up to you what amplifier is more "accurate", the specifications and circuit design do that. It is only for you to decide what amplifier you prefer listening to.
Yes circuit design will give you technical accuracy and Daniel you can have an opinion on which one you feel sounds more accurate.
Lawrence001
19-02-2021, 11:41
From my relatively short experience . . . . .
Power amplifier - Neutral
Source/DAC - Neutral
Speakers - Neutral
Preamp - whatever you like - warm, lush, rich, revealing, transparent or indeed neutral etc.
It's where preferences and tweaks can be made most noticeably to the system. In an ideal scenario all of it would be 'neutral' (of no character) but our ears (senses) aren't all stimulated by the same things (objective sound).
Until I settled on the 'right' (for me) combination of tubes/caps etc for this particular preamp I had 3-4 other amplifiers around just in case and as a reference. Class A, tube, integrated, class D. With this preamp and this power amp they are all sold/for sale.
Room acoustics also play a part in this, a neutral amplifier (preamp/whatever) may sound way too harsh in a 'sharp' acoustic environment. Changing to a warmer/lusher sounding one (maybe rolled off/distorted) may be exactly what the room (and therefore in this case 'the system') requires. At least in the interests of listener satisfaction. At this point measurements and accuracy are a fallacy. They give you the information straight and true, if you don't actually like listening to this information (accurate or not) then there is no point in chasing it really is there?
Depends what you're in it for really.
Personally accuracy/transparency has gotten me very close to where I want to be (huge fan of Quad 57/63's) but had I been simply wanting to increase accuracy/transparency I certainly wouldn't have settled on this preamp. That would have been a mistake as far as my listener satisfaction is concerned.Many ways to skin a cat, having all bar one neutral components and then using the choice of the last one (could equally be a dac as a pre I have found - which is the situation I have happily ended up with) certainly makes life easier than mixing and matching several coloured components. Not to mention cables.
Some people may like putting coloured components together to get to the sound they like. I certainly spent many years doing that, my choices depending on what good value kit came up on Gumtree and the like at any time.
Sent from my BKL-L09 using Tapatalk
The greatest laugh is that whatever you actually think are neutral components you end up sending the whole signal through a pair of speakers which must be the most non neutral component you can have and then you bounce the sound round a room that will have a massive effect again so some of the neutrality folk try and gain can be simply destroyed at the final point of delivery!
I stand to be corrected and after my final listening session I believed the 686 had no soul but it certainly had spirit, a very neutral one.
What i am struggling to reconcile (it seems you were struggling with it too) is the multiple coflicting or contradicting statements you make in them
Soekris - BT2 - 686
I listened to about an hour with this sytem and my final thoughts were that it was a touch analytical and that it confirmed what I thought of digital. If you want a digital system or play digital music predominently this would be a killer system. I have not heard better. Nothing is missing and nothing taken away. There is lots to revel in and enjoy. It can make you marvel at some digital recordings which sound magnificent through this sytem. It does not make the error of plunging down the total detail at the expense of the music route. There is a very nice balance to the BT2 and 686 in this respect and enough weight and warmth and a see through presentation to the recording. This is the best digital set up i have heard in this respect.
You say:
"nothing is missing and nothing is taken away"
"If you want a digital system or play digital music predominently this would be a killer system. I have not heard better"
"This is the best digital set up i have heard"
Here you are actively recommending " the most souless amplifier i have ever heard" :
"I think the 686 would be your dream amp Martin. It has almost no character of its own and is as neutral an amp I have ever heard. Every other amp I have listened too imparts some character like speakers do but the 686 does not. It is as transparent as air, yes the window is not even there!"
Then there is this:
Immediately plugging in the 686 things were different this time. :) Superb clarity, very clear cut soundstage and totally balanced sound from top to bottom. The soundstage was no smaller or larger than my current Series 7 so this was good. This amp has everything. Tonal quality, dynamics, detail in massive ammounts, super smooth grain free sound. Natural and excellent control not only in the bass region but over every frequency...no sibilance! Overall impression Clarity, clarity, clarity. Thats what I wrote in my notes. Fabulous amp and I have to agree with everyone elses opinion on how this amp performs.
The transparency and neutrality of this amp is reference class. I have not heard better anywhere. What a relief to hear what it can actually do. It complimented my Croft 25R superbly. A marriage made in heaven
And once again, you heavily compliment a 686:
In a digital set up it shows total precision and such amazing clarity it is breathtaking! With the inherent low noise floor and wide dynamic range of digital it really is the ultimate tool to convey what was mastered on the recording. Olivers BT2 helps this process very well too.
There is absolutely no sound signature to this amp it is almost invisible yet present at the same time like wind. Yes I know I am talking in slightly illusive terms but the 686 is a special amp and would suit very much those who do not want any character to be imposed on the music they are listening too. I feel this is almost impossible to do with any other piece of gear in the music chain.
Your words have changed whilst you have transfered your opinion from one forum to another.
Yes circuit design will give you technical accuracy and Daniel you can have an opinion on which one you feel sounds more accurate.
No, not an opinion. It's science.
The measurements will declare a clear and obvious advantage or disadvantage in measured performance for one amplifier over another. Whether you enjoy that performance is the only opinion you can have. Accuracy is also not an opinion. It is a measured fact. Your Opinion on what sounds more in line with your reality is an opinion.
You ( a person) cannot declare one amplifier to be more transparent or accurate by listening, when the specifications tell all of the story and your ears do not.
Also, this is not "my opinion" it is scientific fact. Sorry James.
No, not an opinion. It's science.
The measurements will declare a clear and obvious advantage or disadvantage in measured performance for one amplifier over another. Whether you enjoy that performance is the only opinion you can have. Accuracy is also not an opinion. It is a measured fact. Your Opinion on what sounds more in line with your reality is an opinion.
You ( a person) cannot declare one amplifier to be more transparent or accurate by listening, when the specifications tell all of the story and your ears do not.
Also, this is not "my opinion" it is scientific fact. Sorry James.
people here have the right to state their preference Daniel. this is not just about science but how people perceive the sounds they here. That is the ethos here.
I dont post here very often. I don't post anywhere often.
The "Flat Earth" opinions that surrounded this hobby in the 70s & 80s pushed me to abandon the HiFI "people" , magazines and then later forums.
I am once again going to leave forums to those who enjoy discussing HiFI but i wish to leave you with this:
If you get your temperature taken by a Dr, and the gadget they use is acurate to 0.00001%, would you argue with their result or the "accuracy" of it with an opinion based on what your mother thinks by placing her hand on your head? No, i don't think you will. You may prefer having mothers hand on your head than a thermometer up your arse, but when you want accurate results you use the Dr's gadget.
Science is accurate, your ears are not. Your preferences are not science, they are opinion.
Wakefield Turntables
19-02-2021, 12:54
No, not an opinion. It's science.
The measurements will declare a clear and obvious advantage or disadvantage in measured performance for one amplifier over another. Whether you enjoy that performance is the only opinion you can have. Accuracy is also not an opinion. It is a measured fact. Your Opinion on what sounds more in line with your reality is an opinion.
You ( a person) cannot declare one amplifier to be more transparent or accurate by listening, when the specifications tell all of the story and your ears do not.
Also, this is not "my opinion" it is scientific fact. Sorry James.
If only things were so black and white......... :rolleyes: You fail to explain your logic. I'd like you to explain and define how the effects & measurements of each and every hi-fi based variable enabled you to come to your conclusions. Now this is something I'd like to see you produce when the combined effort of numerous companies, numerous highly intelligent individuals cant. I'd really love to see your Magnum Opus.... :goodluck:
What i am struggling to reconcile (it seems you were struggling with it too) is the multiple coflicting or contradicting statements you make in them
Soekris - BT2 - 686
I listened to about an hour with this sytem and my final thoughts were that it was a touch analytical and that it confirmed what I thought of digital. If you want a digital system or play digital music predominently this would be a killer system. I have not heard better. Nothing is missing and nothing taken away. There is lots to revel in and enjoy. It can make you marvel at some digital recordings which sound magnificent through this sytem. It does not make the error of plunging down the total detail at the expense of the music route. There is a very nice balance to the BT2 and 686 in this respect and enough weight and warmth and a see through presentation to the recording. This is the best digital set up i have heard in this respect.
You say:
"nothing is missing and nothing is taken away"
"If you want a digital system or play digital music predominently this would be a killer system. I have not heard better"
"This is the best digital set up i have heard"
Here you are actively recommending " the most souless amplifier i have ever heard" :
"I think the 686 would be your dream amp Martin. It has almost no character of its own and is as neutral an amp I have ever heard. Every other amp I have listened too imparts some character like speakers do but the 686 does not. It is as transparent as air, yes the window is not even there!"
Then there is this:
Immediately plugging in the 686 things were different this time. :) Superb clarity, very clear cut soundstage and totally balanced sound from top to bottom. The soundstage was no smaller or larger than my current Series 7 so this was good. This amp has everything. Tonal quality, dynamics, detail in massive ammounts, super smooth grain free sound. Natural and excellent control not only in the bass region but over every frequency...no sibilance! Overall impression Clarity, clarity, clarity. Thats what I wrote in my notes. Fabulous amp and I have to agree with everyone elses opinion on how this amp performs.
The transparency and neutrality of this amp is reference class. I have not heard better anywhere. What a relief to hear what it can actually do. It complimented my Croft 25R superbly. A marriage made in heaven
And once again, you heavily compliment a 686:
In a digital set up it shows total precision and such amazing clarity it is breathtaking! With the inherent low noise floor and wide dynamic range of digital it really is the ultimate tool to convey what was mastered on the recording. Olivers BT2 helps this process very well too.
There is absolutely no sound signature to this amp it is almost invisible yet present at the same time like wind. Yes I know I am talking in slightly illusive terms but the 686 is a special amp and would suit very much those who do not want any character to be imposed on the music they are listening too. I feel this is almost impossible to do with any other piece of gear in the music chain.
Your words have changed whilst you have transfered your opinion from one forum to another.
I have not even posted any of my review on this forum so your assessment is not accurate.
I am allowed my own opinion whether that is science based or listening based, unfortunately your assessments of equipment seem to be science based which only gets you so far, it certainly does not tell you how something will eventually sound.
The review and everything I have written and your have so painstakingly highlighted ( worryingly) I stand by and do not change.
So what is you issue?
I dont post here very often. I don't post anywhere often.
The "Flat Earth" opinions that surrounded this hobby in the 70s & 80s pushed me to abandon the HiFI "people" , magazines and then later forums.
I am once again going to leave forums to those who enjoy discussing HiFI but i wish to leave you with this:
If you get your temperature taken by a Dr, and the gadget they use is acurate to 0.00001%, would you argue with their result or the "accuracy" of it with an opinion based on what your mother thinks by placing her hand on your head? No, i don't think you will. You may prefer having mothers hand on your head than a thermometer up your arse, but when you want accurate results you use the Dr's gadget.
Science is accurate, your ears are not. Your preferences are not science, they are opinion.
I am allowed an opinion and usually I base it on what I hear rather than what can be measured.
Stryder5
19-02-2021, 14:48
I am allowed an opinion and usually I base it on what I hear rather than what can be measured.
I don’t understand the “attack” on you Jimbo to be perfectly honest. :scratch:
I don’t understand the “attack” on you Jimbo to be perfectly honest. :scratch:
Sometimes folk cannot accept your view or opinion may differ from there own?
It is a straightforward assembly job, more mechanical than electrical I think. If you can wire a plug you can build one of these!
Unless you buy fully populated boards, there is more to it than that.
Unless you buy fully populated boards, there is more to it than that.
Of course Kevin, dont know too many folk who have not built it without using fully populated boards?
Of course Kevin, dont know too many folk who have not built it without using fully populated boards?
The complete set are only available by special request. There was no option on the website when I bought mine.
The amp boards are pre-built now, as is the soft start.
I had to populate the PSU boards and the guardian 686.
The complete set are only available by special request. There was no option on the website when I bought mine.
The amp boards are pre-built now, as is the soft start.
I had to populate the PSU boards and the guardian 686.
When I looked recently there were populated 686 Guardian boards and PSU.
Well regardless of the science or listening ears (or both) I'm looking forward to hearing the 686 Alan kindly built for me. Not had a chance yet too listen (in the middle of a house move). The amp is currently with a friend who reports things like "massive 3d soundstage", "very smooth", "real sense of power" "bass very well defined" "effortless" and so forth. It will be interesting trying it with different preamps. Probably the main pre will be the Phast 6SN7 pre and secondly the passive LDR.
When I looked recently there were populated 686 Guardian boards and PSU.
You are quite right. May be I should have waited. :lol:
It adds quite a bit to the price though, even when considering the parts cost.
You are quite right. May be I should have waited. :lol:
It adds quite a bit to the price though, even when considering the parts cost.
Yeah even with a cheaper case I was looking at £1400 - £1800 for a decent build.
Well regardless of the science or listening ears (or both) I'm looking forward to hearing the 686 Alan kindly built for me. Not had a chance yet too listen (in the middle of a house move). The amp is currently with a friend who reports things like "massive 3d soundstage", "very smooth", "real sense of power" "bass very well defined" "effortless" and so forth. It will be interesting trying it with different preamps. Probably the main pre will be the Phast 6SN7 pre and secondly the passive LDR.
It is a superb amp Edward I am sure you will really like it. I have obviously stated it is a very neutral amp and I have also used the word souless but that is to imply neutrality, it has no real character of its own and is probably the most uncoloured amp I have heard.
I like distortion and colour (valves and vinyl) in my audio so ultimately it was not for me.:)
killie99
19-02-2021, 16:55
Like everything in hifi, it all comes down to what an individual likes and how each piece of equipment interacts with each other.
I'm sure most of us have bought kit we've heard which we thought was the dog's danglies and plugged it in to our system and just been depressed by the sound which has come out the speakers.
Take everyone's opinion with a pinch of salt and make up your own mind, that's what I do.
I remember being told Impulse H2's were the most coloured and bland speakers which were ever produced and my only chance of getting any decent sound out of them was if I used a 4W SET valve amp. I bought a pair and had them in my system for 13 years - for the vast majority of that time with BIG solid state amp's rated in excess of 100W.
It is a superb amp Edward I am sure you will really like it. I have obviously stated it is a very neutral amp and I have also used the word souless but that is to imply neutrality, it has no real character of its own and is probably the most uncoloured amp I have heard.
I like distortion and colour (valves and vinyl) in my audio so ultimately it was not for me.:)
Thanks. I can very much relate to your point about something sounding soulless. Likewise I need the sound to have 'life', it needs to have an emotional engagement where I feel drawn into the music, a feeling of 'being there'. Another way of characterising things is having texture and a richness, but not muddled. And yes these attributes are readily achievable with excellent valve based amplification, or well executed class a solid state (I'm looking at you Sugden). I would not describe the sound of valves as having distortion or colour, I would describe valves having an organic tonality which gets closer to how we experience real sound. So it will be interesting to see if the 686 gives that - of course married with a decent pre and downstream with decent speakers.
I have no complaints with my 686.
It is not soulless in my opinion.
I have no complaints with my 686.
It is not soulless in my opinion.
Sorry Kevin, I think I should have used the word Character rather than soul, I was trying to convey the fact it has very little imprint on the sound of its own ie it is invisible in the music chain because of its low distortion and neutrality, in effect it is doing an almost perfect job as i think Peter Walker once quoted "a straight wire with gain"
As others have pointed out if you want to influence the sound and atylor it to suit your own tastes then you have to use other components in the audio chain. In that respect it is a perfect amplifier as this would be exactly what i think most designers would like to achieve. It is very difficult to do this with say transducers such as cartridges or speakers as these nearly always tend to impart their own flavour or some character.:)
Impossible to do with carts or speakers, But then when you think that the recording itself was monitored, mixed and mastered using loudspeakers that were probably significantly different to what we are using it all starts to seem a bit pointless. You can only ever get in the ballpark with regards to 'accurate' replay no matter how perfect the amp. And it's a big ballpark.
The 686 measures very well but there are even better measuring amps like the Benchmark AHB1. And lots that measure worse but still measure well enough that they are a 'straight wire with gain.'
Once you're past a certain point on the road to perfect amplifier performance I think it would be difficult if not impossible to tell the difference. The 686 is overkill in that respect but then there's nothing wrong with a bit of over-engineering as any Victorian will tell you.
Personally I think it is for the music to have soul rather than the replay equipment. On the other hand we've probably all owned or at least heard systems that did nothing wrong but which were a little 'bland'. All depends on your expectations, what you're used to, and your mood. Imbibing alcohol is still the biggest system upgrade you can do IMO.
I think it all boils down to what you want from your system, or what particular sound you are looking for.
We are all different, which is a good thing. If not this forum (and others) would be a pretty dull place.
Opti-cal
20-02-2021, 11:51
Probably the main pre will be the Phast 6SN7 pre and secondly the passive LDR.
My instincts would suggest the Phast will be a very satisfying listen but always worth trying with others, you never know until you try. I'm excited for you Edward, considering it's a quality pre using 6sn7's.... Hope your mate isn't enjoying it too much!
Thanks Chris.
This is the amp. I'm sure it will make some nice noises.
https://i.imgur.com/1sbEkid.jpg
Opti-cal
20-02-2021, 15:36
Thanks Chris.
This is the amp. I'm sure it will make some nice noises.
https://i.imgur.com/1sbEkid.jpg
Chair has seen many a fine piece of hardware.....
Alan's never sat in it though ;)
hornucopia
20-02-2021, 21:59
Music sounds great via my Opera Consonance horns, via an 86 version.
Sorry Kevin, I think I should have used the word Character rather than soul, I was trying to convey the fact it has very little imprint on the sound of its own ie it is invisible in the music chain because of its low distortion and neutrality, in effect it is doing an almost perfect job as i think Peter Walker once quoted "a straight wire with gain"
This comment has cleared up the confusion I suffered whilst reading your blog, then seeing the "soulless" comment here. You are right that there was a better choice of description available.
I have read back through here and seen a suggestion from Strider5 that it was an attack on Jimbo? It was not intended as such and I regret it was seen that way.
Wherever your blog is posted or wherever you post It is in the public domain. It is my right that I can question what I read. If that be on Art of Sound, or anywhere else. My goal was to understand why there was a difference in your opinion on Art of Sound vs. what you had posted on audio addicts. Not to question your experience of listening and comparing.
As I see now it was just a bad phrase to use and your opinion was more consistent across the forums.
I am glad this has been cleared up.
:peace:
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