OK - here it is then...
Some of the values are approximate.
The design features are
VN66afd / 88afd sounded better than some other types
very low noise power supply ( I noticed recently that alkaline sounds better that lead acid hence the dropper resistors to a BG I guess )
The voltages drops across the o/p stage are optimised to give constant power so hopefully least memory distortion.
I guess the trimmer pot ( to set the bias ) could have another dropper resistor to the battery pos terminal and another decoupling cap.
each channel should have seperate PSU
more current and / or voltage is OK up to about 0.3W across mosfet
of course it does not have to be batteries but TR & diodes would need extra filtering to get the noise down
Which reminds me, did you ever come to a conclusion about snubber caps/resistor etc across the TR secondaries ? I still regard this as a miracle mod for anything that does not have it already.
cheers
mike
Some of the values are approximate.
The design features are
VN66afd / 88afd sounded better than some other types
very low noise power supply ( I noticed recently that alkaline sounds better that lead acid hence the dropper resistors to a BG I guess )
The voltages drops across the o/p stage are optimised to give constant power so hopefully least memory distortion.
I guess the trimmer pot ( to set the bias ) could have another dropper resistor to the battery pos terminal and another decoupling cap.
each channel should have seperate PSU
more current and / or voltage is OK up to about 0.3W across mosfet
of course it does not have to be batteries but TR & diodes would need extra filtering to get the noise down
Which reminds me, did you ever come to a conclusion about snubber caps/resistor etc across the TR secondaries ? I still regard this as a miracle mod for anything that does not have it already.
cheers
mike
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analog_sa said:
Mm... interesting, I will be interested to see how good my mosfet phase splitter pre can get, but I am not expecting it to match my TVC pre.
I was quite suprised that peter says that his TVC softens the treble sometimes.
Peter - what preamp are you using that has clearer treble and better dynamics ? Most of the people that I know that use TVC regard it as the most transparent option available.
mike
I'm using heavily modified ML380S.
On classical and jazz TVC is better: cleaner and more natural.
On electronic music (house, industrial), active preamp seems like a better choice.
The early versions of TVC, were definitely reducing highs; for instance in my friend's system with Alephs 2, he didn't like transformers at all, but they worked great with GC. The current version is better in that regard, and it's hard to say if such reducing occurs.
They are definitely less colored than a ML preamp, yet they still have a sound of their own.
On classical and jazz TVC is better: cleaner and more natural.
On electronic music (house, industrial), active preamp seems like a better choice.
The early versions of TVC, were definitely reducing highs; for instance in my friend's system with Alephs 2, he didn't like transformers at all, but they worked great with GC. The current version is better in that regard, and it's hard to say if such reducing occurs.
They are definitely less colored than a ML preamp, yet they still have a sound of their own.
I've been complaining about this here and in other forums since the day i bought mine. It seems like i was just unlucky to get the spec oriented MK2 'improvement' upon the original. It seems both Mk1 and Mk3 are excellent but based on this experience i'll never again buy anything from S&B before a firsthand listen.
Have you tried using half of the primary instead of all of it ?
I prefer this option.
It means that my 'balanced in' is now psuedo balanced with the earth from the source connected to the centre of a resistive divider across the balanced o/p (and to the case of the TVC)
Using the 102 with a primary centre tap earth is not a good idea as the windings are not symetrical and in these circumstances I do find that treble is reduced.
But I prefer this half primary option even for unbalanced in.
mike
I prefer this option.
It means that my 'balanced in' is now psuedo balanced with the earth from the source connected to the centre of a resistive divider across the balanced o/p (and to the case of the TVC)
Using the 102 with a primary centre tap earth is not a good idea as the windings are not symetrical and in these circumstances I do find that treble is reduced.
But I prefer this half primary option even for unbalanced in.
mike
Since you mentioned it Peter...
Which of these two looks better?
From AD815 datasheet :
Peter Daniel said:
Which of these two looks better?
From AD815 datasheet :
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
carlmart said:
Hi Carlos,
What do you think of the two designs from the AD815 datasheet?
Do you think they have any potential for sounding good?
I need a simple, but very good, preamp to convert the single-ended signal from my DAC(Tube-Lover's TDA1541A kit) to differential for the Zeus amp I'm building.
I suppose it really wouldn't cost too much to just breadboard Figure 51 and see how it works. But, I don't know what type of input transformer to get - 1:1, etc
Another DIY'er in LA!
Hey Acliao,
Good to see someone else from this town is active around here. Are building anything interesting right now?
Any advantage over Figure 51?
I suppose that since Fig 53 has a transformer on the output, it is easier to lock the output impedence at a desired level like the standard differential 600 ohms or lower if need be.
Of course, you could just add another 1:1 line output trans to Fig 51 and get the same effect.
Hey Acliao,
Good to see someone else from this town is active around here. Are building anything interesting right now?
Any advantage over Figure 51?
I suppose that since Fig 53 has a transformer on the output, it is easier to lock the output impedence at a desired level like the standard differential 600 ohms or lower if need be.
Of course, you could just add another 1:1 line output trans to Fig 51 and get the same effect.
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