[cotdt]

Are there any discrete buffer designs for balanced sources? Instead of using an amp I would prefer a buffer since balanced sources already have a high voltage. I don't want opamps I want discrete. Readily available PCBs would also be nice.

 

[burgunder]

A polite bump as I would like to know too.

 

[Epicurean]

I just built one, but unfortunately it isn't working that well. Basically I just built a bipolar power supply and four emitter followers. I'll let you know if I get it to work properly.

 

[TzeYang]

Quote:

Originally Posted by cotdt /img/forum/go_quote.gif Are there any discrete buffer designs for balanced sources? Instead of using an amp I would prefer a buffer since balanced sources already have a high voltage. I don't want opamps I want discrete. Readily available PCBs would also be nice.

try pm kin0kin for help. he just successfully build his balanced diamond buffers.

 

[NelsonVandal]

It seems that ppl is about to ship boards for the LISAIII soon, opamps with discrete buffers. I don't know if it's possible to bypass the opamp stage, just using the buffers. It's just 3 channels, but you should be able to use 2 boards. I don't like opamps either and have no need for more than unity gain.

I think I'm going to ask ppl about this. He has recently started a thread in this forum about LISAIII.

 

[tomb]

Quote:

Originally Posted by NelsonVandal /img/forum/go_quote.gif It seems that ppl is about to ship boards for the LISAIII soon, opamps with discrete buffers. I don't know if it's possible to bypass the opamp stage, just using the buffers. It's just 3 channels, but you should be able to use 2 boards. I don't like opamps either and have no need for more than unity gain. I think I'm going to ask ppl about this. He has recently started a thread in this forum about LISAIII.

Where? Aren't you confusing this with his post on Headwize? It looks like Phil's gotten mad and pulled it anyway and Chu Moy locked the thread. There was some discussion about why he posted an interest-check thread in the DIY section of Headwize instead of the Markeplace, but then he specifically said he was never going to offer a Group Buy, anyway. He apparently wanted someone to take the entire design, build a website, and sell boards. Jrossel, maybe?

 

[tomb]

Quote:

Originally Posted by cotdt /img/forum/go_quote.gif Are there any discrete buffer designs for balanced sources? Instead of using an amp I would prefer a buffer since balanced sources already have a high voltage. I don't want opamps I want discrete. Readily available PCBs would also be nice.

To answer your question, you might research Steinchen's Discrete Buffers that he has under development for the SOHA. They are applicable to other scenario's however, having current-only, unity-gain operation with offset-zeroing capability.

The Jisbos through-hole version, in particular, (circuit designed by Amb) is appropriate as a stand-alone zero-gain current amp. Amb has stated so in the thread himself:
Quote:

Originally Posted by Amb I don't know if it's obvious, but this buffer is also suitable as a standalone unity-gain headphone amp for low-Z headphones. Just add a volume pot and power supply.

Steinchen's Through Hole Jisbos Buffer