Thomas,
No, I do not have any professional experience, I am just basing my responses from your responses and thus making educated decision. Like you said, we are in a DIY world and as such can do anything we want.
The point I was trying to get at is practicality, if the modification you are trying to do has a very small effect on the outcome in which only very sensitive speakers, ears and instruments can only detect, at the cost of a lot of money, I guess you have to weigh this too. Is it really worth it? To be honest, I have tried regular nichicon bypass caps on the driver cathode and tried expensive black-gate caps in place, and you know what, I can not hardly notice the difference. The only reason I have black gate on my amp right now is that I have it available, but if you ask me if I would replace a nichicon with a black gate, probably not. I do not argue that those resistors you are mentioning are better than what is specified, but how much better is the question, if you are going to do your daily listening using your lowther without any crossover and you can hear the difference, then by all means use those resistors, but for the rest of us who do not have lowther and does not have extremely sensitive ears, maybe the wirewound is good enough.
You know, you can go crazy doing this, I saw an amp in San Jose, Ca. where the owner uses silver all over, the wiring, the transformer were specially wound with silver wiring, all black gate with silver interconnect, including his speakers, crossover and everything, the whole thing cost $185,000. Yes it sounds good, well, it better be, for that price. But if you asked me how much better, I do not think its worth it. So for people like us who are also in a budget, we have to be a bit practical too. We have to put quality parts where it is really needed and use lesser quality where its not.
BTW, there is no factory build amp of this type that uses these cathode ww resistors, that idea was from Do-It-Yourselfers like you and me and Mach_Y.
Just a thought, the DRD amp is quite unique that if defies some of my experience in building amps. I was also suprise at some of the things it does. One guys actually told me that using premium parts on the PS and premium resistors on the main circuit does not have much impact on the quality of the sound, and you know what, I am beginning to believe him. This amp is so direct, due to the nature of Ultra-Path design.
Alex Deveza
No, I do not have any professional experience, I am just basing my responses from your responses and thus making educated decision. Like you said, we are in a DIY world and as such can do anything we want.
The point I was trying to get at is practicality, if the modification you are trying to do has a very small effect on the outcome in which only very sensitive speakers, ears and instruments can only detect, at the cost of a lot of money, I guess you have to weigh this too. Is it really worth it? To be honest, I have tried regular nichicon bypass caps on the driver cathode and tried expensive black-gate caps in place, and you know what, I can not hardly notice the difference. The only reason I have black gate on my amp right now is that I have it available, but if you ask me if I would replace a nichicon with a black gate, probably not. I do not argue that those resistors you are mentioning are better than what is specified, but how much better is the question, if you are going to do your daily listening using your lowther without any crossover and you can hear the difference, then by all means use those resistors, but for the rest of us who do not have lowther and does not have extremely sensitive ears, maybe the wirewound is good enough.
You know, you can go crazy doing this, I saw an amp in San Jose, Ca. where the owner uses silver all over, the wiring, the transformer were specially wound with silver wiring, all black gate with silver interconnect, including his speakers, crossover and everything, the whole thing cost $185,000. Yes it sounds good, well, it better be, for that price. But if you asked me how much better, I do not think its worth it. So for people like us who are also in a budget, we have to be a bit practical too. We have to put quality parts where it is really needed and use lesser quality where its not.
BTW, there is no factory build amp of this type that uses these cathode ww resistors, that idea was from Do-It-Yourselfers like you and me and Mach_Y.
Just a thought, the DRD amp is quite unique that if defies some of my experience in building amps. I was also suprise at some of the things it does. One guys actually told me that using premium parts on the PS and premium resistors on the main circuit does not have much impact on the quality of the sound, and you know what, I am beginning to believe him. This amp is so direct, due to the nature of Ultra-Path design.
Alex Deveza
Mach_Y,
I got a hold of Jack Elliano of EP, he was out of town for about a week. I told him about you, he gave me his e-mail address, here it is:
electaudio@aol.com
He said just to be a bit patient, he is just too busy to respond to e-mail right away, but anyway, try that e-mail.
Alex Deveza
I got a hold of Jack Elliano of EP, he was out of town for about a week. I told him about you, he gave me his e-mail address, here it is:
electaudio@aol.com
He said just to be a bit patient, he is just too busy to respond to e-mail right away, but anyway, try that e-mail.
Alex Deveza
I have been emailing Jack Eliano of Electra-Print Audio. He mentioned that the circuit and power supply are not designed to be used with one power supply for both channels. Based off that, I will have to go monoblocks. Any thoughts on this?
Mark
Mark
COMMENTS?
Hi,
A few simple calculations could have given the same answer, no offense though.😎
No doubt the monoblock approach is more expensive but it offers advantages too.
Cheers,😉
Hi,
A few simple calculations could have given the same answer, no offense though.😎
No doubt the monoblock approach is more expensive but it offers advantages too.
Cheers,😉
Re: COMMENTS?
Frank, none taken. However, can you please explain these "simple calculations" so next time I can figure it out myself 🙂 I am here to learn after all.
Would there be any benefit to building the power supplies on seperate chassis? What about putting both power supply sections on the same chassis? If I did this, what connectors / cable are recommended to go between the power and signal section? I would need 7 wires, correct? B+, ground, earth ground, 300b heater and return, and 6AN4 heater and return.
Last, can anyone comments on using the 6AU4GTA tubes? would there be a benefit to going to a 274B for example?
fdegrove said:
Frank, none taken. However, can you please explain these "simple calculations" so next time I can figure it out myself 🙂 I am here to learn after all.
Would there be any benefit to building the power supplies on seperate chassis? What about putting both power supply sections on the same chassis? If I did this, what connectors / cable are recommended to go between the power and signal section? I would need 7 wires, correct? B+, ground, earth ground, 300b heater and return, and 6AN4 heater and return.
Last, can anyone comments on using the 6AU4GTA tubes? would there be a benefit to going to a 274B for example?
Hi mach_y,
I agreed that if the budget is Ok. Pls choose monoblock.
Then no cross talk. But if U mono Block & the driver stage use small rectify tube rectify to supply to the driver & input.
The Big rectify tube such as 5u4 will only supply for the power output stage.
But there must considerate the capital. this method use for times of rectify tube & cap & chokes.
thanks
thomas
I agreed that if the budget is Ok. Pls choose monoblock.
Then no cross talk. But if U mono Block & the driver stage use small rectify tube rectify to supply to the driver & input.
The Big rectify tube such as 5u4 will only supply for the power output stage.
But there must considerate the capital. this method use for times of rectify tube & cap & chokes.
thanks
thomas
hi mach_y,
I test the cheap version of china made 274 tube & 5ua tubes.
The sound quality is the 274b a little best. More detail but smooth than the cheap 5u4.
But this method use in monoblock will more better.
Use one 274b in one stereo & if teh current use more than 180ma. the 274 tube will a little serious. But the 5U4 cansupply more than 225ma, some will more than 250ma. In over 180ma condition, 5u4 still had less serious sound.
But at last i still select 274 because of detail & smooth sound than 5u4 tube.
P.S. My kit I will supply 274B, but certainly U can choose 5u4.
This is flexible & up to U choice.
thanks
thomas
I test the cheap version of china made 274 tube & 5ua tubes.
The sound quality is the 274b a little best. More detail but smooth than the cheap 5u4.
But this method use in monoblock will more better.
Use one 274b in one stereo & if teh current use more than 180ma. the 274 tube will a little serious. But the 5U4 cansupply more than 225ma, some will more than 250ma. In over 180ma condition, 5u4 still had less serious sound.
But at last i still select 274 because of detail & smooth sound than 5u4 tube.
P.S. My kit I will supply 274B, but certainly U can choose 5u4.
This is flexible & up to U choice.
thanks
thomas
Attachments
the rersisters. I all received already from USA.
I will take photo & email to U tomorrow to look which material I use for the kit.
Mike, U got mail.
thanks
thomas.
I will take photo & email to U tomorrow to look which material I use for the kit.
Mike, U got mail.
thanks
thomas.
Mach_Y,
As for different rectifier tube, the reason why a 6AU4 is used is because the circuit demands a very high voltage, I do not know the rating of a 274B, but a 5U4 or 5AR4 will not work due to its lower voltage rating. Actually the 6AU4 is a damper tube and really not designed for audio, but I do not know of any indirectly heated rectifer that has a slow turn-on that has a 700+volt rating.
Jack recommended 5R5GYB, and I have used it, but this tube is a directly heated tube and does not have a slow turn on, so I thought I might as well used SS. So I used 6AU4 instead. SS rectification for the DRD amp is really not that bad, I was reading ron welborne writeup on his DRD amp and he likes SS rectification. Jack Ellianos original design is also SS, so I do not know....
Thomas,
As for your suggestion to provide separate supply for the driver, I do not think this is possible on the DRD amp as the driver is DC coupled to the output tube. On amps that are Resistance-Capacitance or transformer coupled, then what you suggested will work, but I do not think it will work on this amp.
Alex Deveza
As for different rectifier tube, the reason why a 6AU4 is used is because the circuit demands a very high voltage, I do not know the rating of a 274B, but a 5U4 or 5AR4 will not work due to its lower voltage rating. Actually the 6AU4 is a damper tube and really not designed for audio, but I do not know of any indirectly heated rectifer that has a slow turn-on that has a 700+volt rating.
Jack recommended 5R5GYB, and I have used it, but this tube is a directly heated tube and does not have a slow turn on, so I thought I might as well used SS. So I used 6AU4 instead. SS rectification for the DRD amp is really not that bad, I was reading ron welborne writeup on his DRD amp and he likes SS rectification. Jack Ellianos original design is also SS, so I do not know....
Thomas,
As for your suggestion to provide separate supply for the driver, I do not think this is possible on the DRD amp as the driver is DC coupled to the output tube. On amps that are Resistance-Capacitance or transformer coupled, then what you suggested will work, but I do not think it will work on this amp.
Alex Deveza
hi cdeveze,
the best is WE412a. Others choose 6X4 or EZ80,81.
412A Full-Wave Rectifier
(Filament=6.3V @ 1A, PIV=1250V, DC max ouput current = 100ma)
274b spec, visit.
http://tdsl.duncanamps.com/pdf/vm408.pdf
thanks
thomas
🙄 
😱 😕
the best is WE412a. Others choose 6X4 or EZ80,81.
412A Full-Wave Rectifier
(Filament=6.3V @ 1A, PIV=1250V, DC max ouput current = 100ma)
274b spec, visit.
http://tdsl.duncanamps.com/pdf/vm408.pdf
thanks
thomas
🙄 😱 😕hi cdeveza,
not need to say thank you.
U was my friend in my diy road. I know I am not alone.
cheers
thomas 
not need to say thank you.
U was my friend in my diy road. I know I am not alone.
cheers
thomas
I have said it before... and I will say it again... the rectifier should not "sound" like anything. If it changes the sound of your amp, either the power supply or the amplifier circuit or both are bad.
Gabe - I feel like
Gabe - I feel like
Gabevee said:I have said it before... and I will say it again... the rectifier should not "sound" like anything. If it changes the sound of your amp, either the power supply or the amplifier circuit or both are bad.
Gabe - I feel like
If that is the case, then I can just not use tubes, but use solid state and I shouldn't hear a difference?
TO THE BONE...
Hi,
That's oversimplified to say the least...
SS diodes have other disadvantages tube rectifiers don't exhibit.
Noise and instant turn on of the B+ are just the main disadvantages when used in a tube circuit.
Either way I still feel the hybrid rectifier goes along way in the right direction.
Cheers,😉
Hi,
That's oversimplified to say the least...
SS diodes have other disadvantages tube rectifiers don't exhibit.
Noise and instant turn on of the B+ are just the main disadvantages when used in a tube circuit.
Either way I still feel the hybrid rectifier goes along way in the right direction.
Cheers,😉
Mach_Y,
Solid state what?
The power supply is supposed to supply a constant voltage with virtually unlimited current. That is the sign of a good power supply. If you want to you could make an all tube regulated supply that will vary no more than 3-5 volts. But, some power supplies can vary up to 20 volts. This is mostly governed by the tube used. That variation of voltage brings the amplifier into different operating conditions, changing the quality of signal transfer. No more hi-fi, since there is no more fidelity, which is the measure of how faithfully an amplifier reproduces the input, at the output. If it changes the signal along the way... well, I need not repeat myself.
Me, I am a purist when it comes to audio. I strive for my amps to sound live, real. However, that depends on the recording, too. If the recording is bad, my amps will let you know. I too have made amps with flaky power supplies and boy do they make anything sound good.
So, IMHO, if one wants to go with a tube rectifier, look for not only voltage handling but internal resistance. One wants it as low as possible. Or... solid state. With good filtering after, the amp will sound the same either way, as long as the voltage remains the same when changing.
But... now I started another war again for a different thread. Sorry.
Gabe
Solid state what?
The power supply is supposed to supply a constant voltage with virtually unlimited current. That is the sign of a good power supply. If you want to you could make an all tube regulated supply that will vary no more than 3-5 volts. But, some power supplies can vary up to 20 volts. This is mostly governed by the tube used. That variation of voltage brings the amplifier into different operating conditions, changing the quality of signal transfer. No more hi-fi, since there is no more fidelity, which is the measure of how faithfully an amplifier reproduces the input, at the output. If it changes the signal along the way... well, I need not repeat myself.
Me, I am a purist when it comes to audio. I strive for my amps to sound live, real. However, that depends on the recording, too. If the recording is bad, my amps will let you know. I too have made amps with flaky power supplies and boy do they make anything sound good.
So, IMHO, if one wants to go with a tube rectifier, look for not only voltage handling but internal resistance. One wants it as low as possible. Or... solid state. With good filtering after, the amp will sound the same either way, as long as the voltage remains the same when changing.
But... now I started another war again for a different thread. Sorry.
Gabe
fdegrove,
Noise (including spikes, etc)... can easily be filtered away. My amps exibit no noise whatever. In fact, at idle, the noise floor is in the hundreds of microvolts. The tubes are noisier.
Instant on however... may or may not be a concern. Don't know. I think about all those electronic components that have been made in the tube era with SS rectification, let alone batteries. Then I think about how a very small phenomenon can be exxagerated out of proportion.
I just don't know.
Gabe
Noise (including spikes, etc)... can easily be filtered away. My amps exibit no noise whatever. In fact, at idle, the noise floor is in the hundreds of microvolts. The tubes are noisier.
Instant on however... may or may not be a concern. Don't know. I think about all those electronic components that have been made in the tube era with SS rectification, let alone batteries. Then I think about how a very small phenomenon can be exxagerated out of proportion.
I just don't know.
Gabe
Re: TO THE BONE...
Hybrid meaning ss rectifiers followed by tube rectifiers? So you have the benefit ss rectifiers giving a smoother output, but still have the slow turn on of the tubes? or I am missing something? Please fill me in what the other disadvantages SS diodes have... thanks.
fdegrove said:
Hybrid meaning ss rectifiers followed by tube rectifiers? So you have the benefit ss rectifiers giving a smoother output, but still have the slow turn on of the tubes? or I am missing something? Please fill me in what the other disadvantages SS diodes have... thanks.
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