Im looking at the basic shuangang cryogenic for value for money for the valve preamp... 
...in addition, an old schoolchum who is now an electronics engineer I briefly spoke to, suggested that I use a SS buffer with the valve preamp to bring down the impedence without compromising the upper end, as using transformers would typically do...., a helpful well-meening chap; I need to discuss this with him in a bit more detail...
...in addition, an old schoolchum who is now an electronics engineer I briefly spoke to, suggested that I use a SS buffer with the valve preamp to bring down the impedence without compromising the upper end, as using transformers would typically do...., a helpful well-meening chap; I need to discuss this with him in a bit more detail...
Last edited:
Like exactly what is the point?
If you are happy with sound of silicon why bother with a valve?
Either get a decent transformer (eg. Sowter or Lundhal etc) or spend similar money building a quiet power supply for your op-amps.
Or go the Nelson Pass route and use a pair of matched transistors.
(either of the silcon options will be better with battery power supply as long as you don't mind recharging batteries).
Distortion is a byproduct of gain. So you'd expect a unity gain buffer to sound good. The only thing that could beat it would be a "passive preamp" (basically a wire in a box.)
The buffer can do some impedance matching but this tread is way to long to know what you have on both sides of the buffer amp
Have you done any blind testing? It's hard because you need some way to flip a switch and bypass the buffer amp and not change the volume in the process. And of course you need an assistant to flip a coin and then hit the bypass or not. (the switch needs to be silent too, so yo can't hear if the assistant changed the setup.)
But there is no need to assume price determines quality in a small tube buffer amp. The parts are dirt cheap, A $9 tube and a few cents for passive parts is all you need UNLESS you need balanced outputs then you are into $100+ (each) for a decent transformer.
I just bought what turned out to be a pretty good microphone preamp for $29. Proof that you don't have to spend a fortune. This one even has regulated DC heater and a better mechanical design (without an exposed glass tube) You don't need one of these but as an example see the link:
ART-Tube-Studio-Mic-Preamp
I've recently gotten into building studio gear and of course the signal paths are all balanced, I have a goal to learn how to build my own transformers.
The buffer can do some impedance matching but this tread is way to long to know what you have on both sides of the buffer amp
Have you done any blind testing? It's hard because you need some way to flip a switch and bypass the buffer amp and not change the volume in the process. And of course you need an assistant to flip a coin and then hit the bypass or not. (the switch needs to be silent too, so yo can't hear if the assistant changed the setup.)
But there is no need to assume price determines quality in a small tube buffer amp. The parts are dirt cheap, A $9 tube and a few cents for passive parts is all you need UNLESS you need balanced outputs then you are into $100+ (each) for a decent transformer.
I just bought what turned out to be a pretty good microphone preamp for $29. Proof that you don't have to spend a fortune. This one even has regulated DC heater and a better mechanical design (without an exposed glass tube) You don't need one of these but as an example see the link:
ART-Tube-Studio-Mic-Preamp
I've recently gotten into building studio gear and of course the signal paths are all balanced, I have a goal to learn how to build my own transformers.
Last edited:
I think Zaph has finally conceded that a valve preamp will give a super sound regardless of the restrictive thinking with regards to 'solid state' he has so been suffering from all this time; given by the indication that we can take his non-responses to be a 'silent affirmative' in this regard...
I think Zaph has finally conceded that a valve preamp will give a super sound regardless of the restrictive thinking with regards to 'solid state' he has so been suffering from all this time; given by the indication that we can take his non-responses to be a 'silent affirmative' in this regard...
Absolute and utter nonsense.
Read my previous replies. I have given you all the information you require to allow your ME550 to perform at it's best. A valve preamp is NOT (repeat NOT) one of those options. The BEST option is to use the preamp that the amplifier was designed for - an ME preamp.
Do I need to repeat it again to get you to understand?
Zaphod knows ME amplifiers in every detail and it is well known that they perform at their optimum with an appropriately matched pre-amp.A valve pre-amp would require the addition of a buffer stage (solid state) or an power valve(maybe with a transformer in the o/p) to be in the running.There is no justification in terms of noise,distortion,listening or any other parameter that would warrant using a valve pre-amp to precede a solid state amplifier.
ahhh, Zaph ... Ur so serious ... relax ... put on your fav record, have a glass of wine - and unwinnnnnd ...
(Actually now that I have more of a chance, I might take you up on your offer to try out the ME pre-amp - and see how it goes)
Last edited:
Transformer coupling - how to?
I have decided on the JP200 by analogmetric. Can you or anyone show me how to introduce transformer coupling to this circuit??
http://analogmetric.com/download/JP200 Preamplifier Schematic.pdf
(I might also try and find a ME25 preamp at a garage sale - or if Zaph gives me a good price - just to keep Zaph happy )
...however I do like the idea of valve pre-amp coupled with SS amp for best results in both worlds...Just using the basic Guanzo Mattise copy still sounds pretty good, for a $50 valve pre-amp buffer (cannot see it on ebay anymore, but I got 4 of them hehe)
I have decided on the JP200 by analogmetric. Can you or anyone show me how to introduce transformer coupling to this circuit??
http://analogmetric.com/download/JP200 Preamplifier Schematic.pdf
(I might also try and find a ME25 preamp at a garage sale - or if Zaph gives me a good price - just to keep Zaph happy
)...however I do like the idea of valve pre-amp coupled with SS amp for best results in both worlds...Just using the basic Guanzo Mattise copy still sounds pretty good, for a $50 valve pre-amp buffer (cannot see it on ebay anymore, but I got 4 of them hehe)
The only way that a matching transformer can be connected would be in place of R12 A and B, cathode load resistors. ( C3, C5 and R13, R14 are then redundant ). The transformer primary impedance would need to be 100 kohm with a secondary impedance to suit the ME550 amplifier. Given that the JP200 offers a voltage gain of approx. 10 and the transformer will be stepping down the output voltage ,you will end up with no gain or even a loss. Of course the feedback loop could be altered to overcome this gain problem , but I am at a loss as to why this convoluted path should be taken.
Why? The perfect match for an ME550 is an ME preamp. It provides very low distortion, a flat frequency and phase response and, most importantly, the low source impedance that is critical to the correct operation of the ME550.
I have provided you wioth the correct advice, yet you choose to continue to ignore that advice. Why?
(I might also try and find a ME25 preamp at a garage sale - or if Zaph gives me a good price - just to keep Zaph happy
...however I do like the idea of valve pre-amp coupled with SS amp for best results in both worlds...Just using the basic Guanzo Mattise copy still sounds pretty good, for a $50 valve pre-amp buffer (cannot see it on ebay anymore, but I got 4 of them hehe)
Why do you imagine a valve preamp is, somehow, better than a very good SS preamp? You do realise that the higher the quality valve preamps get, the closer they sound to a good SS preamp. That tells me one thing: You WANT distortion.
Because the poster in question steadfastly refuses to listen to common-sense, logic and reason. It would seem he desires distortion. Which makes me wonder why he uses a fine power amp like the ME550.
- Status
- Not open for further replies.