View Full Version : Has anyone tried this Passive Pre?
Well that is not exactly what I was saying...and have you seen the price of decent active pre-amps lately? I am more than happy with the sound of CD that I am personally getting however that wasn't always the case. I was simply speculating that it is the possible cause of the problem for those who are not happy with the medium.
Earlier you wrote:
I'm not keen on using active pre-amps with gain since after many years of experimentation I suspect it is the reason why a lot of people do not rate red book CD as a source compared to vinyl.
I'm simply saying that's certainly not been my experience - quite the opposite, in fact! :)
I've always used an active preamp, and I've always rated red book CD as a high quality music source. Essentially, using an active preamp has never spoiled my enjoyment of CD (or for that matter any digital source).
Marco.
I am more than happy with the sound of CD that I am personally getting however that wasn't always the case. I was simply speculating that it is the possible cause of the problem for those who are not happy with the medium.
Good point Martin - I am often told about vinyl when comparisons are made to my preference for (red book) digital playback . . ."Well you haven't heard vinyl on a good system". But you could also say that those who think CD/digital/file based audio is a poor medium have not heard digital at its best on a good file based audio system ;)
I would totally agree, Tim :)
Marco.
Macca and Marco - in my experience, you can never be absolutist about things like this. Some amps have sufficient gain and input impedance that a passive preamp is perfect for the job - hell, many integrated amps are/were designed like this from the outset (disliked round these parts, but the Cyrus 1 and 2 were perfect examples) and in fact, old Quad power amps (303/405-2 for example) can sound a heck of a lot better once the 33/34/44 is taken away and a passive put in their place.
It's also well possible to make an active preamp that is also totally transparent to the source. Some audiophool manufacturers make it really difficult to justify high purchase prices, but a couple of op-amps with a CLEAN power supply is all you need in many cases and most modern amplifiers NEED the extra voltage to drive them, especially if the interconnects are a few metres long. Forget the likes of the ARC Reference preamps - they're so bad that they need an SE mod every eighteen months and a new model every three years or so to keep sales going...
It's not rocket science you know guys :)
Macca and Marco - in my experience, you can never be absolutist about things like this.
Exactly my point, Dave. I was simply adding some balance to the argument. I'm sure that Martin's point, in some cases, is valid. However, it's simply not true to say that an active preamp universally makes CD sound bad/sub-optimal.
In my view, if it does, then buy a better/more suitable active preamp! ;)
Marco.
+1 :)
:respect: to both of you.
Earlier you wrote:
I'm simply saying that's certainly not been my experience - quite the opposite, in fact! :)
I've always used an active preamp, and I've always rated red book CD as a high quality music source. Essentially, using an active preamp has never spoiled my enjoyment of CD.
Marco.
Okay I was going to start a new thread but let's discuss it here.
You are taking my general point and making it specific to you. I am sure there are a lot of people using active pre-amps who are happy with the CD playback they are getting. But that will depend on the nature of their active pre-amp. I did not say that 'all active pre-amps ruin the sound of CD' as I am not in a position to make that claim. What I am saying is that for those who are dissatisfied with CD - and there are plenty of them - the problem may well lie with their active pre. Now that could mean they need a better active pre-amp. High quality active pre-amps are very expensive. What has your Croft set you back with all the mods? Thousands, I bet. Now how many people own an active pre of that quality? How many can afford one? How many use an integrated amp with an active pre-amp section? A lot. In fact I would suggest the vast majority of people who are unhappy with CD use an integrated with active pre section or use an 'affordable' active pre and that this is the cause of their dissatisfaction with CD.
Why do I postulate this hypothesis (and it is just a hypothesis since you will note I used the words 'I suspect') ?
Because I spent years wondering why CD sounded so poor compared to even budget vinyl playback despite all of the engineering and mathematical specs that said it should sound better. Does that sound familiar? It should since it is what many enthusiasts and the literature (magazines) have been saying since 1983 when 'pure, perfect sound forever' was first launched. I always went along with that view since it perfectly mirrored my own experience. CD sounded hard, glassy, forced; it could not replicate natural instrumental timbre, it did not do well with the reproduction of decay, particularly noticeable with cymbals. Nothing I heard changed that viewpoint. When I went to Scalford in 2012 I was particularly interested to see if any of the CD fronted systems overcame that problem. Not one did. Indeed on the way back my friend asked me if I had learnt anything from the experience and I remarked 'Yes, nobody has a CD player that can do cymbals properly, it's not just me.'
Move forward in time a little and I borrowed a Tisbury passive off Jerry for no other reason that curiosity and general interest since I am a bit of a box-swapper. A revelation! Although the sound was not perfect as there were issues with a lack of bass, slam and attack nevertheless instrumental timbre and decay from CD were reproduced superbly - so well in fact that I spent a week trying to convince myself that I could live with the other shortcomings. I couldn't. Rather than give up I decided to try other passive pre-amps. I ordered the LDR passive pre-amp discussed earlier in this thread. Whilst waiting I came across an NVA passive in the classifieds on here and thought I would give that a go. That turned out to offer everything the Tisbury had but without the lack of slam and attack.
Now that is not to say that some active pre-amps will not give exactly the same results, or perhaps better. I don't know since I haven't tried them all and most are too expensive to box-swap through looking for one that will - unlike passives. So my point is - if you are unhappy with CD replay it is *not the medium* it is the active pre-amp or the active pre-amp stage in the integrated amp you are using that is the problem - so get a better active pre that does not have that issue or if you cannot afford that then go passive and solve the problem that way.
man, that took ages, time for a cup of tea.
Hi Martin,
We're getting things way too complicated here, mate...
I am sure there are a lot of people using active pre-amps who are happy with the CD playback they are getting. But that will depend on the nature of their active pre-amp.
I completely agree with the above. All I was doing was adding my own experience of using an active preamp and stating that, contrary to what you've found, it has never spoiled my enjoyment of CD, compared with my enjoyment of vinyl - no more, no less.
If you wish to extrapolate the discussion and tackle why your experience of active preamps has been different to mine, then that's cool. I should add that in 30 years of using active preamps (I've never actually owned a passive preamp), along with CD players, the situation has been the same. Therefore, in that respect, the Croft isn't doing anything special :)
Marco.
Hope the tea was still hot after that write-up :stalks:
It echoes my experience ...
I always had the feeling that something was held back in my old Quad 34/306 combo until I took the 34 out of the chain and replaced it with a 50$ passive box. The difference was immediately audible. Maybe I was just lucky with the matching, but that experience has converted me to be a believer in the passive approach. The nice thing is that it is quite inexpensive to swap passives as there is not much in them.
Of course, the 34 is not the best pre-amplifier I fully admit.
Hi Martin,
.
If you wish to extrapolate the discussion and tackle why your experience of active preamps has been different to mine, then that's cool. I should add that in 30+ years of using active preamps (I've never actually owned a passive preamp), the situation has been the same. Therefore, in that respect, the Croft isn't doing anything special :)
Marco.
That's fine in your case. But that is not the experience of many enthusiasts, not just me. There was no question for me that at Scalford 2012 the vinyl fronted systems trounced the digital, as did one system using a Nakamichi Dragon (using recordings from an LP12)
Take this thread on PFM for example http://www.pinkfishmedia.net/forum/showthread.php?t=155094 in which a number of people simply cannot get their heads around the idea that there are people who prefer digital replay. Most own and use CD players and consider them inferior to their vinyl set ups, in some cases markedly inferior. They blame the problem on the inherent nature of the medium. I am suggesting the fault lies elsewhere. Maybe I am wrong, like I said it is a hypothesis and only extrapolated from my own personal experience. Given that it is a debate that has raged for 30 years now I think it is worth bringing any new findings to the table for discussion.
Were you not considering purchasing a passive pre-amp? Perhaps that will prove to be superior to the Croft. I will be interested in the outcome.
Hope the tea was still hot after that write-up :stalks:
It echoes my experience ...
I always had the feeling that something was held back in my old Quad 34/306 combo until I took the 34 out of the chain and replaced it with a 50$ passive box. The difference was immediately audible. Maybe I was just lucky with the matching, but that experience has converted me to be a believer in the passive approach. The nice thing is that it is quite inexpensive to swap passives as there is not much in them.
Of course, the 34 is not the best pre-amplifier I fully admit.
I had to make a fresh cup...:)
I don't know what pre-amps Marco has used, I think prior to Croft he had Naim and no doubt he has heard many more hi-end active pre-amps than I have. In my own case I have only used integrateds, a LinnLK1, an XTZ and a Croft Micro-Basic. Interestingly the Croft came closest to acceptable with CD since it did have a lucidity to the sound that nothing else I had used matched. However it had issues with too much gain on the line stage that made any slightly 'hot' master unlistenable. I did consider getting that sorted by Croft (as many owners of that pre-amp range have done) but as for me that pre-amp was ultimately too coloured in its presentation for my taste I instead decided to try something else entirely. Marco's Croft is a far more sophisticated pre-amp compared to the £400 Micro-Basic so it could well be that it offers the best of all worlds, I simply don't know as I have not heard it.
Martin, your experiences in respect of this discussion are equally as valid as mine. I also think that what you're saying makes sense and could explain why some folk feel the way that they do about CD.
You know my opinion on the vinyl vs. CD debate, as it's been discussed here many times: ultimately, I prefer vinyl to CD (as I consider that, at its best, it produces more lifelike sounding results with music), *BUT* that doesn't in any way alter my opinion that CD (or digital) at its best can sound fantastic.
In short, I've never had a problem getting excellent sound from CD, or any aspect digital music replay, with using an active preamp. Although I've never actually owned a passive preamp, every time I've tried one, the results have always been worse than when using a high-quality active preamp. That has been my experience to date.
I was originally going to buy the Khosmo passive advertised as a back-up for the Croft, should I ever be without it for any reason, but mainly to obtain the stepped attenuator included in the package. Since I'm now going for the remote control version of that attenuator, it's not really worth buying the preamp.
However, it'll be interesting comparing your NVA P90 with the Croft at the forthcoming bake-off. Rest assured that if I prefer your passive preamp, not only will I acknowledge the fact, but I will investigate the use of high-quality passive preamp options accordingly :)
Marco.
Martin, your experiences in respect of this discussion are equally as valid as mine. I also think that what you're saying makes sense and could explain why some folk feel the way that they do about CD.
.
Thank God for that - I was beginning to think my incredibly long-winded explanation had totally missed the mark :)
I'm not attempting to introduce a new chapter in the CD vs Vinyl debate, in fact I was trying (and failing) not to do that lest it divert the discussion into that tedious realm. I was more making the point that many set ups although they are fine with vinyl do not do CD justice, which would explain a lot. To my knowledge no-one has ever mentioned this before either on forums or in the magazines. So I thought it worth mentioning.
The active v passive bake off will certainly be interesting and like you I will have no problem declaring the Croft to be superior if that is what I think. I do not consider my hi-fi purchases to be an extension of myself and I am not insulted or upset if people criticise them or disagree with them. My only problem would be that if the Croft turns out to be better than the passive(s) with CD that I cannot really afford to buy one of them for myself. So if that turns out to be the case you better keep a close eye on it or it might 'walk off', don't forget I am a Scouser... ;)
anthonyTD
21-04-2014, 12:00
The Analog output stage of a CD player can in many cases, make or break an otherwise good player, just as a badly designed, or miss-matched preamp, a system is only as good as its weakest link!
A...
LOL... in that case, log out and enjoy your cuppa! :lol:
Seriously.. I think that if you had stuck with the Croft and had some resistors changed you would be very happy. The Crofts do come with high gain, it's well documented, I had it changed on mine and the difference was huge. CD has a tendancy to come across loud and nasty sometimes depending on the mastering but get the match right between the cd player and the pre, your laughing.
Your cd player could also be part of the problem too.. Have the output stage looked and and tweeked, again... huge benefits.
Joe - the Croft for me made everything sound like it was recorded in 1970, be it on vinyl or CD. It was a laugh riot and communicated the music superbly but I decided that in the end it was not the sound I was looking for, I wanted a system that gave a 'straight from the desk' sound and that really showed up all the elements of the production as the engineer would hear them. To that end I changed both my pre-amp and loudspeakers and by chance (and a little bit of instinct as to what might work) I now have something pretty close to that. So all's well that ends well as the Bard did say.
Just a point for those suggesting the CD player may be the problem - if I were to stack up all the Cd players I currently own they would reach the ceiling - that is *not* an exaggeration. If I added in the ones I have tried and moved on and those I have heard elsewhere then they would reach the roof. The CD player is not the issue here.
my only problem would be that if the Croft turns out to be better than the passive(s) with CD that I cannot really afford to buy one of them for myself. So if that turns out to be the case you better keep a close eye on it or it might 'walk off', don't forget I am a Scouser... ;)
Lol! :D
I do not consider my hi-fi purchases to be an extension of myself and I am not insulted or upset if people criticise them or disagree with them
Me neither. Also, my opinions on hi-fi are never 'written in stone', and so if I learn something new that invalidates my previous opinions, I simply update them accordingly.
That's the way I've always been. I hate people with rigid and inflexible opinions on audio. The fact is, ALL of us are on a continual learning curve, and so we should happily embrace that fact.
Marco.
I wanted a system that gave a 'straight from the desk' sound and that really showed up all the elements of the production as the engineer would hear them.
That's precisely what my Croft does *now* (or at least as close as possible to my perception of such). However, it's taken years of tweaking and no little amount of expense to get there, as in stock form it was way too 'cuddly'/old-fashioned sounding for my tastes.
IME, all the older Croft preamps were voiced that way as standard. The current range perhaps goes too far in the opposite direction.
Marco.
That's precisely what my Croft does *now*. However, it's taken years of tweaking and no little amount of expense to get there, as in stock form it was way too 'cuddly'/old-fashioned sounding for my tastes.
IME, all the older Croft preamps were voiced that way as standard. The current range perhaps goes too far in the opposite direction.
Marco.
Do you mean the older Crofts were more neutral (for want of a better word) or that the new ones are too neutral? It's not really clear from your post. I've not heard the regulated versions anyway I am only commenting on the micro basic which is the cheapest in the new range.
Macca and Marco - in my experience, you can never be absolutist about things like this. Some amps have sufficient gain and input impedance that a passive preamp is perfect for the job - hell, many integrated amps are/were designed like this from the outset (disliked round these parts, but the Cyrus 1 and 2 were perfect examples) and in fact, old Quad power amps (303/405-2 for example) can sound a heck of a lot better once the 33/34/44 is taken away and a passive put in their place.
It's also well possible to make an active preamp that is also totally transparent to the source. Some audiophool manufacturers make it really difficult to justify high purchase prices, but a couple of op-amps with a CLEAN power supply is all you need in many cases and most modern amplifiers NEED the extra voltage to drive them, especially if the interconnects are a few metres long. Forget the likes of the ARC Reference preamps - they're so bad that they need an SE mod every eighteen months and a new model every three years or so to keep sales going...
It's not rocket science you know guys :)
Good post Dave. I do think that preamps are more difficult to get to sound good / transparent than power amps, and there's a lot of respected preamps out there that don't hold up to a simple volume pot and some RCA jacks.
Funny that you mention "a pair of opamps" as I've popped open my LFD DLS and the preamp box looks a lot like the LFD phono stage designs e.g. 2x opamps with 4x regulator ICs with big RC filters after the regs, PCB has no tracks and is hardwired. I haven't opened the power supply box yet but it's heavy.
Firebottle
21-04-2014, 14:02
'The CD player is not the issue here.'
Appreciate that you've tried a few Martin :eek: but I think it is. Not from a whatever make is flavour of the month aspect, but from the output level standpoint.
Given that a normal preamp is going to be expecting say 200 to 300 mV, most CD payers are 2V output, that's a lot to cope with.
Has anybody tried using a quality attenuator, Rothwell springs to mind, when feeding the CD into the pre?
:cool: Alan
The Black Adder
21-04-2014, 14:58
Joe - the Croft for me made everything sound like it was recorded in 1970, be it on vinyl or CD. It was a laugh riot and communicated the music superbly but I decided that in the end it was not the sound I was looking for, I wanted a system that gave a 'straight from the desk' sound and that really showed up all the elements of the production as the engineer would hear them. To that end I changed both my pre-amp and loudspeakers and by chance (and a little bit of instinct as to what might work) I now have something pretty close to that. So all's well that ends well as the Bard did say.
Must have been something wrong with something then because the Croft certainly doesn't 'make' music sound poorly produced or recorded or old fashioned.... It will reproduce what is true enough to what's recorded more than a lot of pre's out there.
Anyway, glad you have what you want.
'The CD player is not the issue here.'
Appreciate that you've tried a few Martin :eek: but I think it is. Not from a whatever make is flavour of the month aspect, but from the output level standpoint.
Given that a normal preamp is going to be expecting say 200 to 300 mV, most CD payers are 2V output, that's a lot to cope with.
Has anybody tried using a quality attenuator, Rothwell springs to mind, when feeding the CD into the pre?
:cool: Alan
Yep. It 'flattened' the sound for me. Didn't like its effect at all.
Hi Martin,
Do you mean the older Crofts were more neutral (for want of a better word) or that the new ones are too neutral?
Nope. The older Crofts (and by those I mean the ones that use 6SL7 output tubes, as opposed to ECC83s), in my experience, sound somewhat softer/fuller than current Crofts, which can sound a little bright/lightweight and/or forward in comparison.
Much of that presentation is to do with the inherent sonic signature of their respective output tubes, which to an extent can be ameliorated by modifications to other parts of the circuit. What I've done with my preamp is modify it in such a way as to hear what the circuit is truly capable of, by removing the bottleneck of (justifiably) 'built to a price' components, supplied as stock.
In essence, having heard the current range of Croft preamps, and whilst liking them, IMO my modded Charisma-X acts as more of an 'open window' - although it should do, given that I've spent about £1500 on components modifying it! :)
Marco.
Must have been something wrong with something then because the Croft certainly doesn't 'make' music sound poorly produced or recorded or old fashioned.... It will reproduce what is true enough to what's recorded more than a lot of pre's out there.
Anyway, glad you have what you want.
Who mentioned poorly produced or old fashioned? Not me. Let me give you an example
of what I mean: Robert Plants first three solo albums are very well produced but are very early eighties digital recorfings. Super clean and slightly 'glassy' sounding. Through the Croft they sounded richer and fuller with no glassinrss, you could not tell that they were digital recordings at all. Some might say they preferred the way the Croft presented them but frankly if the Croft is right then evrrything else is wrong.That is colouration, there really is no question about it. Did it make them less enjoyable from a purely musical point of view? No. Was it accurate to the source? No. Some wouldnt care but I do. I don't want my amplification to add its own conyribution to the production. I did enjoy the Croft for several years and it was an important part of the learning curve for me and helped me identify the way I wanted to go.
anthonyTD
21-04-2014, 17:09
Hi Alan,
That would certainly be the case with old design pre-amps as source equipment of the day had relatively low output voltage, however, most modern preamp designs take into account that modern source equipment has a healthy 2v line level signal. There really is no need for a preamp to have gain these days,[unless of course the power amp is deliberately designed to have an unusually low input sensitivity] what is important is their ability to drive the cable and input load combination of modern designed power amps.
'The CD player is not the issue here.'
Appreciate that you've tried a few Martin :eek: but I think it is. Not from a whatever make is flavour of the month aspect, but from the output level standpoint.
Given that a normal preamp is going to be expecting say 200 to 300 mV, most CD payers are 2V output, that's a lot to cope with.
Has anybody tried using a quality attenuator, Rothwell springs to mind, when feeding the CD into the pre?
:cool: Alan
Some might say they preferred the way the Croft presented them but frankly if the Croft is right then evrrything else is wrong.That is colouration, there really is no question about it.
Indeed, Martin.
The point is that that coloration in question can be removed by the mods both Joe and I have carried out to our respective Croft preamps, whilst retaining the inherent musicality provided by the circuit Glenn designed, in order to create an exceptionally good preamp - one which can compete with others costing many thousand pounds more.
At the end of the day, all audio equipment is built to a price, so in a preamp when decent (but nothing special) components are upgraded for better ones of the same electrical value, in an otherwise very well designed circuit, the only thing that can happen is improved fidelity...
As Joe has slowly been modifiying his preamp in line with mine, that is precisely what has happened and what he's heard for himself :)
Marco.
Indeed, Martin.
The point is that that coloration in question can be removed by the mods both Joe and I have carried out to our respective Croft preamps, whilst retaining the inherent musicality provided by the circuit Glenn designed, in order to create an exceptionally good preamp - one which can compete with others costing many thousands more.
As Joe has slowly been modifiying his preamp in line with mine, that is precisely what has hapepened and what he's heard for himself :)
Marco.
I don't doubt it for second. But we were talking about unmodified micro basics not modded 25r or charisma. And if Joe has modified his amp to sound less coloured then why suggest that the micro basic in standard form is not coloured and that it is more likely something was wrong with the set up. Bit of a non seqitor, surely?
'The CD player is not the issue here.'
Appreciate that you've tried a few Martin :eek: but I think it is. Not from a whatever make is flavour of the month aspect, but from the output level standpoint.
Given that a normal preamp is going to be expecting say 200 to 300 mV, most CD payers are 2V output, that's a lot to cope with.
Has anybody tried using a quality attenuator, Rothwell springs to mind, when feeding the CD into the pre?
:cool: Alan
Alan I dont have any means of measuring the output voltage of my cd players but it is unlikely that they are all 2v. Also Tony C recently remarked that the output voltage of the Technics slp1200 is only 1.2 volts. I've got two of them. Also I have tried Rothwells at 10dB attenuation that was not an improvement. I don't come up with these conclusions off the top of my head you know. I spend a lot of time experimenting with various combinations and a lot of critical listening goes on.
The Black Adder
21-04-2014, 17:39
I don't doubt it for second. But we were talking about unmodified micro basics not modded 25r or charisma. And if Joe has modified his amp to sound less coloured then why suggest that the micro basic in standard form is not coloured and that it is more likely something was wrong with the set up. Bit of a non seqitor, surely?
All I did was to have the gain reduced.... that's all I did.... OK!?
I found that after I did that everthing sounded less forced and harsh to which I felt that you heard the very same thing. All I suggested was to send it up to Glenn and have a couple of resistors changed to make a bit smoother. Too much gain can make sound very forward and a bit edgy.
But my 25 basic and my Micro25 did NOT make my collection sound like it was recorded in 1970... I just don't get that so I suggested that something could have been wrong somewhere, that's all... No trouble here.
All pre's are coloured in some way or another, you just have to persevere with some to make em fit.
Now that you have it sorted, that's cool... enjoy!
I don't doubt it for second. But we were talking about unmodified micro basics not modded 25r or charisma. And if Joe has modified his amp to sound less coloured then why suggest that the micro basic in standard form is not coloured and that it is more likely something was wrong with the set up. Bit of a non seqitor, surely?
I never said that the Micro Basic in standard form wasn't coloured - dunno where you got that from? :scratch:
What I said was that it (and others from the current range) have an inherently different sonic signature from the Croft preamps from a earlier era, and briefly outlined the differences between both.
Marco.
Joe
No trouble here either. There could be a number of reasons why we disagree as to whether the micro basic is coloured. It did take me a long time to come to that conclusion as it is not immediately obvious. I perhaps gave the impression with what I said earlier thst it is a blayent and obvious charteristic whereas in fact it is a quite subtle effect. Not everyone would notice and even fewer would care.
The Black Adder
21-04-2014, 18:35
Joe
No trouble here either. There could be a number of reasons why we disagree as to whether the micro basic is coloured. It did take me a long time to come to that conclusion as it is not immediately obvious. I perhaps gave the impression with what I said earlier thst it is a blayent and obvious charteristic whereas in fact it is a quite subtle effect. Not everyone would notice and even fewer would care.
No probs... I see where your coming from now.
If you do ever find yourself looking at another active pre then try for one of the older Octal valve versions. As Marco said, they do have a very different signature to the new types. They are all round much more wholesome sounding.
A passive will let you see in to the recording, whilst a decent active will let you get her knickers off! :cool:
Lol. I've got into enough trouble removing knickers to last me a lifetime already ;)
hifinutt
21-04-2014, 18:40
All I did was to have the gain reduced.... that's all I did.... OK!?
I found that after I did that everthing sounded less forced and harsh to which I felt that you heard the very same thing. All I suggested was to send it up to Glenn and have a couple of resistors changed to make a bit smoother. Too much gain can make sound very forward and a bit edgy.
But my 25 basic and my Micro25 did NOT make my collection sound like it was recorded in 1970... I just don't get that so I suggested that something could have been wrong somewhere, that's all... No trouble here.
All pre's are coloured in some way or another, you just have to persevere with some to make em fit.
Now that you have it sorted, that's cool... enjoy!
I find my tisbury pre a little harsh and edgy at louder volumes , does that mean its too much gain for my class A msb s200 power amp which was absolutely superb and awesome with my vibe
If you do ever find yourself looking at another active pre then try for one of the older Octal valve versions. As Marco said, they do have a very different signature to the new types. They are all round much more wholesome sounding.
That's essentially it. Octal valves, such as 6SL7s, sound very different indeed from smaller ECC83/12AX7 types - and it is *that* which gives old and new Croft preamps their respective 'house sound' :)
Marco.
kininigin
21-04-2014, 19:24
Joe
No trouble here either. There could be a number of reasons why we disagree as to whether the micro basic is coloured. It did take me a long time to come to that conclusion as it is not immediately obvious. I perhaps gave the impression with what I said earlier thst it is a blayent and obvious charteristic whereas in fact it is a quite subtle effect. Not everyone would notice and even fewer would care.
Having got both the micro basic and the micro 25 i agree with your comments! When i first switched to the 25,it wasn't immediately obvious that it was better (i had different speakers then mind).After extended listening it then came apparent that it was less coloured imo.Not that the basic is massively coloured as you say!
fiddlemaker
21-04-2014, 19:26
FWIW the latest Croft line stage uses a 12bh7a valve, not ecc83.
kininigin
21-04-2014, 19:35
Hi Martin,
Nope. The older Crofts (and by those I mean the ones that use 6SL7 output tubes, as opposed to ECC83s), in my experience, sound somewhat softer/fuller than current Crofts, which can sound a little bright/lightweight and/or forward in comparison.
Not heard the older crofts but i tend to agree regarding the new ones! I got round that by using 5751 valves which to me had a better balance and fleshed the sound out a bit! I currently have a RTC french valve in the line stage,which came with the second 25 i bought.This i feel exaggerates the basic croft sound and i'm not too pleased with it having giving it plenty of time to get used to it! I will be going back for some 5751's i think! Unless there are others to consider!
kininigin
21-04-2014, 20:27
All I did was to have the gain reduced.... that's all I did.... OK!?
When i was using the 5751 valves they reduced the gain of the 25! Maybe that's the reason i prefered these valves rather than the sound of them,if you know what i mean!
Not heard the older crofts but i tend to agree regarding the new ones! I got round that by using 5751 valves which to me had a better balance and fleshed the sound out a bit! I currently have a RTC french valve in the line stage,which came with the second 25 i bought.This i feel exaggerates the basic croft sound and i'm not too pleased with it having giving it plenty of time to get used to it! I will be going back for some 5751's i think! Unless there are others to consider!
I agree, Darren. Also try some NOS Teslas or Brimars. Much of the signature you describe is down the use of current production valves (JJs or Electro Harmonix), which quite frankly, are not very good.
The problem is that Glenn needs to use valves that are easily obtainable and sonically consistent, which is something that doesn't always apply with NOS valves. Unfortunately, however, whilst current production fit that criteria, sonically, they're inferior to the best NOS varieties, which is why it pays to experiment :)
Marco.
kininigin
21-04-2014, 21:54
I agree, Darren. Also try some NOS Teslas or Brimars. Much of the signature you describe is down the use of current production valves (JJs or Electro Harmonix), which quite frankly, are not very good.
The problem is that Glenn needs to use valves that are easily obtainable and sonically consistent, which is something that doesn't always apply with NOS valves. Unfortunately, however, whilst current production fit that criteria, sonically, they're inferior to the best NOS varieties, which is why it pays to experiment :)
Marco.
I will look out for some to try.Do you know any decent suppliers? The 5751's i bought,were from someone on here,so not too sure where to look! I don't know but i would be supprised if Glen did use the current production valves in his own set-up! They do keep the cost of his amps down though...well until you swap them that is :lol:
Hi Darren,
Sorry I'm late to this... I'll PM you details of some good suppliers. Remind me if I forget!
In the meantime, since we were talking earlier about the internals of preamps, here's the inside of my (now highly modified from standard) Croft Charisma-X:
http://imagizer.imageshack.us/v2/800x600q90/843/qukz.jpg
Not exactly pretty (although well laid-out mostly by Glenn), but it's a simple and very effective (all hard-wired) circuit, which sounds superb! :)
Close-up of the valves used... From left to right: NOS Mullard M8214/ECC83 (on top of a NOS Mullard 85A2 voltage regulator) > 2 x NOS Russian Melz 69NS (6SL7) > 1 x GE 5691 (6SL7) > 2 x RCA VT-229 (6SL7):
http://imagizer.imageshack.us/v2/800x600q90/838/l2sc.jpg
Marco.
kininigin
02-05-2014, 20:35
Hi Darren,
Sorry I'm late to this... I'll PM you details of some good suppliers. Remind me if I forget!
.
Hi Marco,
Only just noticed this and yep that would be great!
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