which is the best coupling transformer for a balanced 1 bit dac chip?

[richt]

hi folks

i want to remove all op amps from this player and the da converter chip is a mash 1 bit da converter mn6471m
with an impressive sound. but i am looking to install a transformer
and adapt a tubed section tha i designed.
transformer should do balanced in /unbalanced out to drive
a 12 au7 mullard tube.

thanks
richt

[Bas Horneman]

Hi Richt,

RaleighAudio uses the Lundahl LL1674

http://www.raleighaudio.com/passive_output.htm

I've also seen the LL1527 being used on the internet.

Good luck.

[richt]

thank you very much for your reply!

have you tried that design?
have you tried sowter & lundhal?
do i have to use some kind of low pass filter?

i am trying this design inside of a teac esoteric vrds10
the transport that wadia uses on their top priced transports.
i am having good results but i am looking for the optimal biaset
for the mullard 12au7.

thank you
richt

[Bas Horneman]

I have the RAKK dac by RaleighAudio. The passive version. Works and sounds great. I don't think you have to use any filter because the transformer is in itself a filter. Lows and highs are filtered out by the tranformer...

I have not tried any other because the RAKK comes with the LL1674..I might try the LL1527XL just for fun one day...(but I can't right now because someone is evealuating my RAKK dac)