Transformer based voltage gain + unity gain stage?

[soundcheck]

Hi folks.

I am planing to do a bit of reengineering on my system.

Currently I am running a Sabre 32 (Buffalo) passive SE into a Tripath 2021B
feeding my 98db/W SPL speakers. All SLA driven. Sounds quite nice.

What's causing me headaches is the questionable performance of the opamp on the input and the losses associated to the outputfilter-inductors.

I am now thinking of using an output transformer of e.g. 1:4 (6,4V) on the DAC to go out differential. Voltage gain would be done by the transformer.

On 8R speakers I'd end up with approx. 5,2W if using an unity-gain-amp.
I think that should be OK.
A 2nd secondary on the transformer I could even use for feeding my subwoofer crossovers.

What I can think of for amplifcation is a nice differential unity gain amp
with a high input impedance and dc-coupled replacing my Tripath amp.
The amp should work on +-12V supply rails and be of highest quality.
Feedback should be avoided if possible. It should not be too complicated to build.


I'd really appreciate any hints or advise on above idea. ( I don't have too much background on amp-design ).


Thx.

Cheers

 

[AndrewT]

have a look through the thread
http://www.diyaudio.com/forums/pass...urce-follower-configurations.html#post1592491

 

[DF96]

It is difficult to avoid feedback if you want a unity gain amp. The obvious circuit, source/emitter follower, has very high levels of feedback although all within one stage.