Thanks 6L6, always good to hear from you and please...... no more awesome builds....you depleting my wallet big time 
What about transformers? I know from the threads a lot of folks here including myself have used 400VA but have seen some use 500VA or even 600VA. Are there any benefits to upping the VA's and even going for the Antek "shielded" variants? My previous build had my shielded wire going to the chassis.
What about transformers? I know from the threads a lot of folks here including myself have used 400VA but have seen some use 500VA or even 600VA. Are there any benefits to upping the VA's and even going for the Antek "shielded" variants? My previous build had my shielded wire going to the chassis.
About transformer because I don’t know enough to not even know enough
I have a question I am still a beginner and still learning about the transformer being bigger . Maybe because these amplifiers are so low power bigger doesn’t mean better even if it’s just a little bit better . I think I remember reading one of papas Pass articles on class a amplifiers in transformer size . If you could correct my memory was he mentioning something about a transformer to her three times bigger then required to have some benefit ?. Even the larger transformer used inside a preamp being considered grotesquely large had benefit?. I also remember Paul from PS audio mentioning the exact same thing about using a much larger transformer then was actually required . And Paul from PS audio in his very early beginning days when he developed his very first preamp using an oversized transformer was one of the keys to his success . And I believe Carver audio he also went for those oversized exotic transformers with a very strange to typology when I first saw it I almost thought it was a hybrid switch mode power supply.
Correct me and set me straight is this one of those scenarios where are you using a distortion analyzer or some other sensitive piece of equipment and you’re trying to get a number as low as possible so you go overboard . Example 0.000005 some crazy tiny number . Or is there a Merritt behind a transformer when that large long hi db bass note hits the power can be delivered with quick recovery ?.
I also have read in more than one situation being mentioned having custom wound transformers for example 6 AMP windings transformer custom wound on the 8 AMP coil.
Thank you, seeking education.
I have a question I am still a beginner and still learning about the transformer being bigger . Maybe because these amplifiers are so low power bigger doesn’t mean better even if it’s just a little bit better . I think I remember reading one of papas Pass articles on class a amplifiers in transformer size . If you could correct my memory was he mentioning something about a transformer to her three times bigger then required to have some benefit ?. Even the larger transformer used inside a preamp being considered grotesquely large had benefit?. I also remember Paul from PS audio mentioning the exact same thing about using a much larger transformer then was actually required . And Paul from PS audio in his very early beginning days when he developed his very first preamp using an oversized transformer was one of the keys to his success . And I believe Carver audio he also went for those oversized exotic transformers with a very strange to typology when I first saw it I almost thought it was a hybrid switch mode power supply.
Correct me and set me straight is this one of those scenarios where are you using a distortion analyzer or some other sensitive piece of equipment and you’re trying to get a number as low as possible so you go overboard . Example 0.000005 some crazy tiny number . Or is there a Merritt behind a transformer when that large long hi db bass note hits the power can be delivered with quick recovery ?.
I also have read in more than one situation being mentioned having custom wound transformers for example 6 AMP windings transformer custom wound on the 8 AMP coil.
Thank you, seeking education.
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These are amplifiers with 50W (total, I.E., counting both channels) of output.
The recommended transformer is 300VA - which is essentially 300W.
So the recommended transformer can supply SIX TIMES the output power.
Making the transformer bigger doesn’t do much, particularly in a Class-A amplifier, as the current demands are constant. Recovery like you are asking is more a function of capacitor value, but the recommended cap values are also quite large... and making those significantly bigger actually has some disadvantage as well.
0.000005 is a ridiculously small number that I realized you used for illustration, but is so infinitesimally small that it is laughable... you are talking about 1 part in half a billion.
I guess it all boils down to this - the recommended values are humorously large to begin with. There are no “just good enough” values in the PSU, if you build it as designed it will be overkill.
If you wish to build it to overoverkill numbers, that’s entirely up to you, but I’m fairly convinced it makes no additional benefit.
The recommended transformer is 300VA - which is essentially 300W.
So the recommended transformer can supply SIX TIMES the output power.
Making the transformer bigger doesn’t do much, particularly in a Class-A amplifier, as the current demands are constant. Recovery like you are asking is more a function of capacitor value, but the recommended cap values are also quite large... and making those significantly bigger actually has some disadvantage as well.
0.000005 is a ridiculously small number that I realized you used for illustration, but is so infinitesimally small that it is laughable... you are talking about 1 part in half a billion.
I guess it all boils down to this - the recommended values are humorously large to begin with. There are no “just good enough” values in the PSU, if you build it as designed it will be overkill.
If you wish to build it to overoverkill numbers, that’s entirely up to you, but I’m fairly convinced it makes no additional benefit.
Hi Everyone
Have few queries around PSU
I have completed PSU. Tested O/P with Murata diode bridge(diode board) and square block bridge, I thought square block bridge had lower voltage drop.
With diode board I am getting 30V and square bridge around 29v. This is for F5 turbo.
Do you get consistant dc voltage on output of PSU(no load) , mine vary, every other day I read, I get a different voltage 28 to 30 range(21 to 23 just with secondary).Could that be due to input voltage changes?
Is there any difference in O/P of a toroidal Transformer primary configured for ~220v vs ~110v?
Have few queries around PSU
I have completed PSU. Tested O/P with Murata diode bridge(diode board) and square block bridge, I thought square block bridge had lower voltage drop.
With diode board I am getting 30V and square bridge around 29v. This is for F5 turbo.
Do you get consistant dc voltage on output of PSU(no load) , mine vary, every other day I read, I get a different voltage 28 to 30 range(21 to 23 just with secondary).Could that be due to input voltage changes?
Is there any difference in O/P of a toroidal Transformer primary configured for ~220v vs ~110v?
I' like to build a power supply/chassis I can use to swap amp builds in. I recently picked up 4 56000uf 65 volt caps. My question is should I use the power supply board and ommit 4 of the the capicitors or just build a custom power supply? And what size transformer should I get? I'm thinking larger than the typical 300vamp. BTW I will be housing the build in a 5U chassis and starting with a Aleph J build.
Thanks, Jeffrey
Thanks, Jeffrey
Depends on what amps you plan of building. If you are going to try all the Firstwatt designs (which is totally awesome) just get an Antek AS-4218 since it's the biggest shielded one they make. More than big enough for the job.
Making a simple supply from those big caps and a few filter resistors is a good idea. I've always wanted to make an amp with a bunch of can caps in the middle, just because it looks cool.
Making a simple supply from those big caps and a few filter resistors is a good idea. I've always wanted to make an amp with a bunch of can caps in the middle, just because it looks cool.
If I keep only a rectifier, but I want to mantain the whole filter board, how can I join the part 1 with the part 2? How must I manage ground? Ground comes from the 0V of the transformer and should enter the filter board. Where?
See diagram -
Attachments
