Creating a differential signal from a single-ended signal for bridged amps

[Steve Eddy]

Originally posted by planet10
This one is fairly respectable... a couple Joes have compared it favorably with much higher priced transformers.

http://www.edcorusa.com/transformers...wsm10k-10k.htm

And it's not even $10. No more "big money" excuses now.

se

[Peter Daniel]

Originally posted by Steve Eddy

No more "big money" excuses now.

Indeed, it would be hard not to try it now.

[mikelm]

I used a mosfet ( VN66AFD ) based simple phase splitter for a few years before I went over to S&B102.

I'm currently upgrading it to see just how good I can get it to sound.

If you are interested I will post a cct

mike

[Peter Daniel]

Of course I'm interested.

[mikelm]

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

[mikelm]

Of course, a valve phase splitter might sound nicer...

[analog_sa]

Of course, a valve phase splitter might sound nicer

Probably, but having tried lots of them, to my ears nothing beats a transformer. The bad rap PP amps have is largely due to the phase splitters.

[mikelm]

Originally posted by analog_sa


Probably, but having tried lots of them, to my ears nothing beats a transformer. The bad rap PP amps have is largely due to the phase splitters.

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

[Peter Daniel]

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.

[analog_sa]

was quite suprised that peter says that his TVC softens the treble sometimes

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.