Main reason I did not listen to it is that my phono cables are too short.
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Main reason I did not listen to it is that my phono cables are too short.
My minor intermittent hum has come back to my BB3.
I removed all of the internal ferrites, as they looked messy and it has made no difference - the hum got no worse.
One thing I did notice while I was in there was that there was a small white spot under one of the power capacitors on the bottom of the case.
As a precaution I have ordered some new Nichicon capacitors. I also took the opportunity to order a few sheets of Silent Coat 2mm damping sheet to use on the CD player, Phono Stage and amplifier.
I would probably put a bit in the Pre 90, if I could work out how to get the case apart. :scratch:
I rate the Silent Coat very highly.
Same.Quote:
Originally Posted by Jimbo
Anywhere I've used it its noticably improved sound, even in amps and other non-moving part gear.
Its well worth using and works great.
Tthe 4mm stuff is even more effective.
Probably worth trying in anything as even DACs are subject to vibration and I think SS amps benefit too. I use it particularly well in my Croft amps which have thin metal cases and lots of rattle glass bottles!:lol:Quote:
Originally Posted by Gazjam
Great sounding biscuit tins tho!
Worked well in both my Dac and Preamp, as well as when modding a couple of disc spinners.
Interested to hear how Kevin gets on with his.
Yes it was a surprise for me.
It won't be going in the pre-amp.
I can't get the case off. It most have hidden screws under the feet.
CD player, Phono Stage and amp will be done. I bought three sheets (to the wind?).
The phono stage and CD will get the most attention.
I'm wondering if this Silent Coat might help me...Quote:
Originally Posted by CageyH
There is a small amount of mechanical buzz comes from my Musical Fidelity A5 integrated (only audible when close to it, the buzz only comes from the unit, doesn't come from the speakers, and does not increase with volume). It's a common thing with these amps, where users suggest it may be a consequence of varying voltages.
Maybe Silent Coat could deaden the sound to some degree, what do you think?
sounds like the tx.. it might help a bit
I agree it sounds like you may have a slightly noisy transformer in your MF A5.
I'd consider trying a DC blocker. The Audiolab DC Block is pretty good, and I currently use one to cure a buzzing toroidal transformer in my set-up.
If its buzzing, its vibrating!:lol:Quote:
Originally Posted by Pigmy Pony
Cures the buzz but does it knacker the sound?Quote:
Originally Posted by Desmo
Yes, I have read of some users have used DC blockers with some success, with others saying it killed the dynamics to some degree.Quote:
Originally Posted by Jimbo
'Buzzing' might not be the best description for the sound, but it is not like the kind of hum you might hear associated with earthing problems. In a phone conversation with John Sampson of JS Audio last year I mentioned it as an afterthought (it really doesn't bother me much) he just said something along the lines of 'very common, just one of those things'.Quote:
Originally Posted by Jimbo
Still might be worth me trying this Silent Coat though.
Sorry about the thread hijack Kev. :)
I have 3 very buzzy toroids in my Croft amps which I can hear very clearly when up close. When I used Silent Coat on the cases there was a noticeable reduction in noise but also less vibration getting through to my valves. I should have had them ripped out and put in a separate box but alas Glenn is no longer with us sadly.Quote:
Originally Posted by Pigmy Pony
It is no coincidence that Glenn top of the range preamps were indeed two separate boxes with the rattly toroids separate from the rest of the delicate tubes.
Worth checking the central bolt in your toroid for tightness.
Sometimes just giving it a nip with a pair of pliers can solve buzz.
I've used silentcoat directly on transformers, didn't make it sound worse.
Avoid RF treatment around transformers though, found it kills the top end.
Built a DC blocker and fitted it to my balanced mains a while back?
Quickly removed it, as dynamics and air took a hit.
System dependant as usual of course, YMMV
No worries.Quote:
Originally Posted by Pigmy Pony
I built one of these https://sjostromaudio.com/pages/inde...yle-heavy-duty into my Mod 686.
Does what it says on the tin.
I did try an external DC blocker first to see if it was DC related or pure mechanical hum.
Fortunately for me, it was DC related. My amp is now silent.
The Audiolab DC Block did not knacker the sound in my setup but of course YMMV. There are quite a lot of +ve reviews of the Audiolab on the Richer Sounds site: https://www.richersounds.com/audiola...RoC0CUQAvD_BwEQuote:
Originally Posted by Jimbo
But peakload is only 600 VA. With 800VA in my amp, it is simply not big enough.
I have just added a 375 x 250 x 2mm sheet of Silent Coat to my Big Bottle 3 phono stage, coating exposed areas of the internal case, so front panel, sides, lid, base and rear panel. Some panels have had more Silent Coat applied than others. I am really not expecting to hear a difference.
Tomorrow I will attack the CD player based on the instruction on the Lampizator website. If I am feeling strong, I will,do the amplifier as well, but that is mainly going to be the upper panel, which will probably take an entire sheet quite happily. Maybe I should have bought a few more….
You may end up taking some off as I found weirdly you can go too far!:eek: Will be interesting what you make of it Kev. It might be best to listen to your system a piece at a time rather than Silent Coat everything and then you will know wants contributing the biggest effect. Just a thought....Quote:
Originally Posted by CageyH
Surely damping the case is a good thing? It will cut down on vibrations, that could affect the delicate valves?
There is very little damping near the PCB.
Yes of course damping the BB3 with valves in it should make a noticeable difference but I found if you completely coated the case it could dampen things down a bit too much. But personal listening experience is what matters.Quote:
Originally Posted by CageyH
I was just suggesting to try listening to your system after coating one piece of kit at a time so you can attribute differences or not?
Ah, understood. I have not completely covered the case, in fact there is not a single panel that has been covered 100%.
The plan for the CD player is to put a patch on the top part of the case. This is quite flimsy, and a little on the mechanism.
The 686 has a flimsy lid. The rest is pretty solid, and access is not great to the rest of it. I certainly don’t want to put any on the heat sinks.
I think your biggest bangs for bucks may come from the BB3 then maybe CDP. Even DACs can benefit as those clocks don't like vibration!:)Quote:
Originally Posted by CageyH
With Solid state gear (686) I think it is the caps that benefit from anti vibration. Some manufacturers are building amplifiers with panel structures that are anti vibration including Teac who do a lot on their CDT to stop vibration round the drawer mechanism.
If you take a scroll down this article you can read about capacitors and vibration.
https://eepower.com/technical-articl...r-technology/#
:thumbsup:
Damping capacitors is another tweak that works, I did several before and after comparisons modding different pieces of kit, all improved the sound.
Heat Sinks?
Dont be too fast to dismiss damping them Kev, you obviously dont want to stop them functioning put a small piece on top can alter its resonant frequency, which can made a change to the sound.
Worked to good effect in my Oppo and Audiolab players.
Yes,
Its a bit of a rabbit hole, and sorta easy to dismiss, but vibration is worth making the effort to mitigate.
Just depends how far you want to take it I guess?
In my opinion, its worth doing a deep-dive on this stuff, it really works.
To James’ point about OVERdampening:
Yes, you can do that, but not for the obvious reason?
Once top level vibrations are damped, going further its about changing the resonant frequency (vibration) and that can interact with something else giving a less preferred effect.
Think of applying a damping sheet to the underside of a turntable plinth…. Would change SOMETHING in the sound, right?
Would you prefer it though?
Apply the Tweak, listen and compare, keep if you like it.
Job done. Move on to the next one.
:thumbsup:
Job is done.
I actually had 4 sheets, so the BB3, CD player and 686 have been done.
Having checked the specs of the silent coat, it seems safe enough to use on the 686 heatsinks, so a strip was fitted on both.
The lid and base have been done, as were the front panel, and a few small bits fitted on the rear panel, as there was not much room here.
I have turned the system on, and a) it still work, b) it still sounds good.
Was it with it? Not at the listening levels I use when the family is home, as there is very little sound pressure to cause vibrations.
When they go out, I will wind the wick up a bit.
Keep us posted.Quote:
Originally Posted by CageyH
A question:
While heat sinks are responsible for the lion's share of heat dissipation, some of this heat will also be lost through the casework. If the amp's case feels warm to the touch when in use, this must mean that some of the heat escapes this way. In which case applying the silent coat may be insulating the amp to some degree?
think the 'to some degree' is the point. the heat syncs should dispose of the vast proportion of it. heat syncs no doubt are bolted to the case so will heat up a bit, but the case is big enough to stay just warm with the air around itQuote:
Originally Posted by Pigmy Pony
Agreed - the sound deadening material is, I assume, applied to the inside of the case.
There's going to be some insulation effect from lining the inside of a case, I don't see how there can't be. Whether it will raise the internal temperature enough to reduce the service life of the components inside I don't know.
Putting it on a heatsink is inevitably going to reduce its ability to dissipate heat, again hard to say if that would eventually cause a problem.
The heatsink forms part of the case.
It looks a bit like this - https://www.audiophonics.fr/12611-th...-4mm-black.jpg
Adding a small strip of the Silent coat to the internal face of the heatsink is going to have very little affect on the operating temperature of my amp.
There are holes in the top that will vent the case, and the fins on the side will have a better dissipation affect than the vertical inner surface of the heatsink.
The main source of heat will be the output devices.
The heat from them is largely conducted to the fins of the heat sink where it is dissipated by convection (and to a smaller extent by radiation).
Any radiant heat produced within the case is in turn dissipated by radiation and convection from the exterior of the case. All the sound deadening material will do is to absorb the heat which will eventually be conducted through and dissipated from the exterior of the case.
Well this Silent Coat does look rather like that stuff people put behind their radiators to reflect heat back into the room, but at the end of the day I trust you guys' judgement on this more than my own :)Quote:
Originally Posted by Barry
So it will reflect heat back into the heatsink and make the amp cooler? :thumbsup:
As the amp does not run hot, I don't think it is an issue.
Quote:
Originally Posted by CageyH
it shouldnt do much really. the fans may cool more slowly but it wont be an issue unless it runs very hot, in which case i wouldnt advise it.. ie, on a mf a1000.... that amp doesnt look to be a hotty
I shouldn't think it would effect at 686 -they don't run that hot and there is lots of room int the case. Unless its running a lot of the time in Class A which it probably doesn't as it is a Class A-B amp.
The 686 case barely gets warm to the touch, even when being on for a complete day.
With the wick turned up, vinyl replay sounds a bit clearer now. I suppose that the Herbie’s tube dampers and the Silent coat have helped reduce vibrations.
Today, I fancied a change, so I swapped my Topping Pre90 out for my Firebottle KIN.
Vinyl is still very enjoyable to listen to.
I still need to put my RME DAC back in, and have a listen to the digital side.
After about an hour of listening, I think I want to change my pre.
Ideally for a hybrid pre like the KIN, but with balanced inputs/outputs and remote source selection and volume control.
I think I prefer this sound the the Pre90, which I have been using for a long time.
Interesting stuff Kevin,
Alan's gear is top notch, not surprised your enjoying it so much.
Had his phono stage a few years back, it sounded terrific.
My experience is that a good Pre can make a big difference sound wise?
None of that "straight wire with gain" nonsense. :)
I've been running the Pre90 for a few Months in my system as well, and been very impressed by it.
Well... for all the "Hifi" reasons anyway?
It replaced my PS Audio BHK preamp (Im a sucker for a "Giant Killer") and whilst I enjoyed the lack of slight valve background hiss (probably cos the gain structure of my setup) the Pre90 was no where near as "real"sounding and emotionally impactful.
Thats what I look for in a system.
The Toppings very clear with literally zero background noise...sure, but after some months with it now, I feel theres something "missing", or more likely "added" and off about its sound, at least in my System.
I initially thought it might be that it was so "technically correct" it wasn't adding any of its own euphonic flavour like a lot of Pre's do?
But its not that.
Its not clinical sounding either, exactly, but I'm more aware now with the Pre90 and the new Dac having ran in more from new, that it puts a bit of a "cold sheen" over the music.. I'd liken it to adding a sharpness filter to a Jpeg image?
Technically it hits the marks with low SINAD and such, but theres definately something missing and an artificial aspect to its sound.
Its missing the magic sauce, basically, and shows that measurements arent the be all and end all.
Theres better out there,sure, but for the spend its OUTSTANDING.
Took a punt on it, but its flavour doesn't suit my likes/system... wish it would have taken £600 to tick that box but sadly not.
Think its a nested feedback Op-Amp based design, and I've found with some kit in the past that can add an artificial flavour to the sound.
Dunno, no expert, I just hear what I hear.
Synergy is everything, so just in my system to my ears.
Worth noting though that some folks reckon the Pre90 goes head to head with the much more expensive Benchmark LA4, so its obviously not a mediocre amp.
So Im moving on from the Pre90 as well.
Its a great amp but feel its holding my system back, especially in the areas that give me the fizz.
I'm missing what the PS Audio BHK Pre brought to the table, but dont miss the slight valve hiss.
Fantastic value though, and easily expandable with an additional well priced add on box if you need more inputs.
Good to be able to swap back and forth between pre's Kevin, see where your mood takes you at the time! :)
The Topping's only real fault is low input impedance, especially with the balanced inputs (2Kohm) and the unbalanced is still only 9.6kohm.
So if your source does not have low output impedance frequency response is going to skew off downwards especially with balanced connection.
The Benchmark is much more compatible in that regard (80Kohm balanced and 37Kohm unbalanced).
I don't know if this is the reason why you both seem slightly dissatisfied with the Topping, but there it is. Maybe look at the output impedance of your DACs and phono stages. If you're going in balanced you want them to be less than 200 ohm.
The Dacs output impedance is around 27.5 Ohms, so pretty low?
Its just a system sound preference thing with me I think.
I plumbed the BHK pre back in to confirm the sound change and yup, the "magic" came back.
Confirmed that Pre amps can make a difference...again.
Yes should not be any issue there. You must just like those noisy valves ;)Quote:
Originally Posted by Gazjam
I like the sound of valves gently hissing as it lets me know my amp is on!:)