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Cary SLP-90 preamp power supply

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Been watching this from a distance. Donning flame suit... I have to agree with Michael here. The human brain has an almost infinite capacity to rationalize and massage the messages coming in from the sensory inputs according to what the emotional needs of the individual are at the time. Until we have a complete theory of hearing and audio (we don't yet!) then people will just have to accept some individuals can hear things that others either do not hear, or refuse to accept that they're hearing.

I'm not saying people are necessarily in denial about not hearing things. The most likely account is that they are not hearing the distinctions and simply refuse to accept that other people do and rationalize that assumption based on their erroneous belief that we know everything there is to know about the brain/auditory interface.
 
Until we have a complete theory of hearing and audio (we don't yet!) then people will just have to accept some individuals can hear things that others either do not hear, or refuse to accept that they're hearing.

I'm afraid that's nonsense. You don't need to have "a complete theory of hearing and audio" to demonstrate the ability to hear a difference. You just need to demonstrate the ability to hear a difference. 😀 This, of course, is much different than making an empty claim about hearing a difference.

Basic engineering still works once you limit claims to those demonstrated with ears only. You know, the same engineering that allows us to image atoms or send spacecraft to planets hundreds of millions of miles away. Or, for that matter, write nonsense that can be read almost instantly by millions of people around the world.
 
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That's why I was donning my flame suit. We disagree completely on this and I don't expect our disagreement to end here. But I think it's very good for you to know that there are people who vehemently disagree with you and others on this. We just don't speak up very often for fear of being attacked. 🙂 Over and definitely out on this thread.
 
I think reality is the opposite: we can measure lots of things we can't hear - our hearing is weak and easily fooled..
The ability to hear and sense one's surroundings is one of the basic evolutionary requirements of living creatures. Developed over billions of years it is probably the most refined of all our senses. It is not our hearing that is weak and easily fooled, it is our brains that can not accurately decipher or accept the signals that our ears are sending, that is fooled. And just as training and practice can make one a better dancer, juggler, video game player, singer, guitarist, etc. So, can training and practice make one a better listener. And that is why some people can hear better than others. Whether thru genetics or training to discount someone's ability to hear better than another flies in the face of logic. That would be tantamount to believing that musicians have achieved their abilities only thru repetition and not through a highly developed sense of hearing. regards, 808
 
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Basic engineering still works once you limit claims to those demonstrated with ears only. You know, the same engineering that allows us to image atoms or send spacecraft to planets hundreds of millions of miles away. Or, for that matter, write nonsense that can be read almost instantly by millions of people around the world.[/QUOTE]

Nobody disputes that..What I do dispute are those that say that there is no performance in putting in a film cap vs a lytic in the power supply..Just by nature,a 35uf film cap is more effective then a 35uf lytic regardless of type.
I have over 11,000 caps from k40s to vitamin Qs to Gudeman to Westcap to Pyramid,and Jensen paper in oil caps as well as Russian Teflons,Sonicap Teflons and film caps,Solen film and ton foil,Multicaps,Mundorfs,Clarity caps,716ps,Hovlands,Obligatos,Dynamicap,thetas,and Vcaps,and the list goes on.
These caps all sound different by nature from each other regardless of dielectric.
Now getting back to lytics vs the film caps. A few can't tell the difference and that's fine but truthfully, I don't think some of you even bothered to find out if there is a difference. Lytics have stress on the dielectric and this is how they are able to get large amounts of capacitance into a small area..There are compromises tho from doing this in the form of leakage and if there was no performance difference,why bother making film caps at all?
I have a sencore Lc102 which is one of the most thorough cap analyzer ever made. I also own over 284 tube amps and all but 6 are vintage..Now granted many are duplicate mono amps such as Dyna mk3s and Mac Mc60s and Heath w5ms and Eico hf50s and Hf60s,Fisher 55a.Heath W6ms as well as many stereo amps like Leak St50s and Mac Mc275s and Mc240s and the list goes on.
The point is,I have upgraded and modded every type amp and preamp under the sun and while I can sweep two different amps for freq response, and linenerity,power, and distortion and get similar numbers, the amps can have a much different sonic flavor just by virtue of FB level or dampening,or the way the amp processes the music thru its output trafos.
Out of all the mods and upgrades I have done,the biggest sonic difference came from using film caps in the power supply either as the main filters or a bypass on lytics. I don't believe in just putting .1 or .22 across a lytic because I never found one bit of difference going that small..I usually bypass with 20% of the lytic's value so if I have a 100uf lytic,I bypass it with a 20uf or larger film cap.
The other thing I find makes a difference is using Schottky diodes because they are very quiet.
I will be putting up a pair of Mc30s I rebuilt using an all film cap supply and a choke and I can will show you the distortion and power numbers as well as the 1khz,10khz and 20khz sq waves..These amps will make 52 watts using a GZ34 and when I using a 5u4,it drops to about 46 watts..I'm using Rca 6L6gc black plates. I use two different distortion analyzers.
These are the analyzers I use and on this particular amp is an Mc225 and it makes over 30 watts both channels driven. That I just did a rebuild with 820uf panasonics in the doubler and a dual 100uf FT down stream and a single 50uf FT.It says 30.34 watt and the bottom Tek is showing 15.5v and when you square that and divide by the 8 ohm load,it shows the exact power reading on the HP.
 

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exeric said:
Until we have a complete theory of hearing and audio (we don't yet!) then people will just have to accept some individuals can hear things that others either do not hear, or refuse to accept that they're hearing.
It is easy to check if someone is really hearing something: just check that they can hear it! That is, ears alone unaided by sight or other information channels.

The most likely account is that they are not hearing the distinctions and simply refuse to accept that other people do and rationalize that assumption based on their erroneous belief that we know everything there is to know about the brain/auditory interface.
No. It is rational to accept that a signal change which according to circuit theory is very small and therefore according to known psychoacoustics should be inaudible, and indeed is found to be inaudible in 'ears-only' testing, is actually inaudible. The burden of proof is on those who claim that they can hear things which accepted science says they cannot hear, and which seem to disappear when ears alone are tested.

But I think it's very good for you to know that there are people who vehemently disagree with you and others on this. We just don't speak up very often for fear of being attacked.
We are well aware that such people exist. They are very vocal; on some audio sites they form the dominant majority. Fortunately that is not the case here; they may be a majority (I don't know) but they are not dominant. Such people are rarely attacked here, but their false views are often rightly criticised.

DAK808 said:
Whether thru genetics or training to discount someone's ability to hear better than another flies in the face of logic.
I don't discount someone's ability to hear better than another. I also don't discount people's ability to sincerely believe they are hearing something when the necessary information entered their brain via some channel other than their ears.

michael samra said:
Just by nature,a 35uf film cap is more effective then a 35uf lytic regardless of type.
More effective as what? A charge reservoir? No. More effective at lightening a wallet? Yes. More effective as feedstuff for bragging? Yes.

Lytics have stress on the dielectric and this is how they are able to get large amounts of capacitance into a small area..There are compromises tho from doing this in the form of leakage and if there was no performance difference,why bother making film caps at all?
Leakage does no harm in a PSU cap. Film caps are made because people want to buy them. In some cases this is because there is a legitimate circuit reason for doing so.
 
AC electric motors are a great example of where a film cap is a much better choice over 'lytics. The run cap gets abused.

That is very true and if you remember,many companies such as Marantz and Pederson and early Williamson uses a paper in oil cap for the first stage filtering right after the dual Dampers in the case of the Marantz 2.. Supratek uses film caps in all their later preamps and when I upgrade the earlier ones i put in a 100uf motor run and a 50uf motor run off the GZ34..

Here are some of the caps I use and you see quite a variety of lytics and film caps and motor runs.I just put of couple of each up to get them in the picture.
 

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