A lot of years ago, I made the experiment to try a PSU with full MKP SCR capacitors with same voltage and value that the BG, we made blind test with several persons including me & we all noted the sound differences easy.
A challenge for those of you who are really curious . . .
When it comes to hearing the implication of different ESRs, you can do an easy Double Blindfold test.
Start with either an LCRCRC, or a CRCRC B+ filter.
Power the output stage from the Second (middle Cap).
The Last Cap powers the driver / input stage that drives the output stage
Make sure to use the very best capacitor for the middle Cap, with the lowest ESR.
Now, wire a 10 Ohm resistor in series with the middle Cap; and wire an SPST switch across the 10 Ohm resistor.
(if your middle Cap does not have an ESR far less than 10 Ohms, get a different cap, or parallel up a number of caps to get the total ESR reduced)
Listen with the switch open, the total resistance is the cap ESR + 10 Ohms.
Listen with the switch closed, the total resistance is the cap ESR.
Do not pay attention to whether the switch is open or closed, just keep changing the switch position back and forth, while Listening for a Difference.
First do the listening test with a push pull output stage (where the difference is harder to hear).
If you do not hear a difference with the push pull stage, then do a listening test with a single ended output stage.
If you still do not hear a difference, then please . . . stop talking about the ESR being a major factor.
When you hear about ESR and sound differences, Remember that old 1960s era statement:
"Trust but Verify".
Capacitors have many differences: ESR, Leakage; Inductance, and Dissipation Factor.
There is not just one factor to consider that might cause sound differences.
That is why I chose the 10 Ohm series test method, to make it more fair for testing ESR differences.
A series 10 Ohm resistor does Not change the capacitor's Leakage; Inductance, and Dissipation Factor.
Good Luck with the listening!
Just my opinions
When it comes to hearing the implication of different ESRs, you can do an easy Double Blindfold test.
Start with either an LCRCRC, or a CRCRC B+ filter.
Power the output stage from the Second (middle Cap).
The Last Cap powers the driver / input stage that drives the output stage
Make sure to use the very best capacitor for the middle Cap, with the lowest ESR.
Now, wire a 10 Ohm resistor in series with the middle Cap; and wire an SPST switch across the 10 Ohm resistor.
(if your middle Cap does not have an ESR far less than 10 Ohms, get a different cap, or parallel up a number of caps to get the total ESR reduced)
Listen with the switch open, the total resistance is the cap ESR + 10 Ohms.
Listen with the switch closed, the total resistance is the cap ESR.
Do not pay attention to whether the switch is open or closed, just keep changing the switch position back and forth, while Listening for a Difference.
First do the listening test with a push pull output stage (where the difference is harder to hear).
If you do not hear a difference with the push pull stage, then do a listening test with a single ended output stage.
If you still do not hear a difference, then please . . . stop talking about the ESR being a major factor.
When you hear about ESR and sound differences, Remember that old 1960s era statement:
"Trust but Verify".
Capacitors have many differences: ESR, Leakage; Inductance, and Dissipation Factor.
There is not just one factor to consider that might cause sound differences.
That is why I chose the 10 Ohm series test method, to make it more fair for testing ESR differences.
A series 10 Ohm resistor does Not change the capacitor's Leakage; Inductance, and Dissipation Factor.
Good Luck with the listening!
Just my opinions
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I use all film PS caps and Nichicon Gold for cathode bypass
which I bypass with poly film and polystyrene caps. ApexJr has some good 75uF 600v film caps for cheap, $5 each that I use with great results. I’m going to try an all poly bypass cap set up soon but it will take up a lot of room. I do notice a difference without the film bypass on the electrolytic cathode caps. The amp has more detail and speed to it. Not a huge amount but it is audible. My test is if my girlfriend notices it, im not crazy. At least I tell myself Im not crazy.
which I bypass with poly film and polystyrene caps. ApexJr has some good 75uF 600v film caps for cheap, $5 each that I use with great results. I’m going to try an all poly bypass cap set up soon but it will take up a lot of room. I do notice a difference without the film bypass on the electrolytic cathode caps. The amp has more detail and speed to it. Not a huge amount but it is audible. My test is if my girlfriend notices it, im not crazy. At least I tell myself Im not crazy.
The cylindrical caps have a more rounded sound.
The square metal film caps can sound a bit edgy I find.
The square metal film caps can sound a bit edgy I find.
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I opened up my CD player a year ago before I got rid of it for a PI music player. There was a Chinese transport inside on one side and a PCB on the other. I have never seen so many electrolytic caps and sub power supplies inside. Amazing. But none of this helped the CD missing the transport and landing in the case. Never mind.
Valve amps can be like that. You can go decoupling the cathode resistors with the lowest ESR you find, but are quite happy with the imperfections of the OPT, the speakers, the 120Hz sidebands it adds to a tone, the hum/buzz when its on...
If you really think it makes a difference do the science and take some measurements.
Valve amps can be like that. You can go decoupling the cathode resistors with the lowest ESR you find, but are quite happy with the imperfections of the OPT, the speakers, the 120Hz sidebands it adds to a tone, the hum/buzz when its on...
If you really think it makes a difference do the science and take some measurements.
Placebo medication continues to have therapeutic benefits, even when test subjects know they’re taking sugar pills. It may be similar with capacitors: expensive, good looking, large and colourful caps will genuinely sound better, especially to the person who paid for them, and their buddies. May also be true for cables, power leads, turntables, speakers, whole amplifiers, listening rooms ….
<< May also be true for cables, power leads, turntables, speakers, whole amplifiers, listening rooms ….
May also be the case that there are audible differences which listeners with very carefully controlled testing protocols can hear.
May also be the case that there are listeners who simply make each A-B comparison with a totally open mind, which includes being ready to note "no difference" on the number of occasions where this is the case. Not all listeners are gullible, and human hearing can pick up micro differences, especially when trained to do so.
May also be the case that there are audible differences which listeners with very carefully controlled testing protocols can hear.
May also be the case that there are listeners who simply make each A-B comparison with a totally open mind, which includes being ready to note "no difference" on the number of occasions where this is the case. Not all listeners are gullible, and human hearing can pick up micro differences, especially when trained to do so.
In blind testing I've seen some very interesting results- some things that you know won't make a difference don't, and some things you think will don't either.
However,
Capacitors when used as bypass caps to maintain a DC voltage across a resistor tend to not be as audible as a capacitor in an application where they are coupling signal. But, they generally have to have some very different parameters or values to make an audible difference. At a get together I went to years ago people could distinguish values, but not brand. Some very upset people with lots of expensive parts learned something that day. The ceramic disc caps performing audibly identical to the really nice audiophile stuff was pretty funny to see reactions once it was revealed.
This looks like the job 180uF bad boy should be fine. The voltage may be a tad overrated for a cathode bypass. You could use this and a switch for a 180uF electrolytic. Then you could perform a blind test.
https://www.claritycap.co.uk/products/csa.php
Actually ceramic I would be wary of. Some types the capacitance drops significantly (Y5V) as the voltage increases. This can produce distortion at low frequencies where there's significant AC component across the device. This can be measured quite easily. If you are going to bypass an electrolytic again the distortion will be highest when there is significant AC voltage. Thus you would need a large value metal film.
https://www.claritycap.co.uk/products/csa.php
Actually ceramic I would be wary of. Some types the capacitance drops significantly (Y5V) as the voltage increases. This can produce distortion at low frequencies where there's significant AC component across the device. This can be measured quite easily. If you are going to bypass an electrolytic again the distortion will be highest when there is significant AC voltage. Thus you would need a large value metal film.
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