I've thought about the Singing bush, still undecided... If the Semisouth is a pinpoint machine in the Babelfish ᄅſ, and ZM seemed to prefer the IRF, it seemed a natural progression to the THF-51s.
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I never had intention to leave message about preferring IRFP in said amp
I have no preference ........ simply not having that amp in use
sadly or not , I have just one pair of ears and finite number of chambers , in which I can put A class amp
I have no preference ........ simply not having that amp in use
sadly or not , I have just one pair of ears and finite number of chambers , in which I can put A class amp
Thank you for the clarification ZM.
OK, moving the Babelfish ᄅſ down the build list and the Schade back to the top
OK, moving the Babelfish ᄅſ down the build list and the Schade back to the top

I got one amp up and running today. Everything went smoothly, no excitement. Except for my heart.
The THF-51S is runnng at 2.2 A, Vgs = 35.7 V, with bias of -4.10 V.
I hooked the amp up to a test speaker and it is now playing my favourite radio station, CBC (Canadian Broadcasting Corporation). No unusual behaviour to report (with the amp, that is). Tests will come later.
The THF-51S is runnng at 2.2 A, Vgs = 35.7 V, with bias of -4.10 V.
I hooked the amp up to a test speaker and it is now playing my favourite radio station, CBC (Canadian Broadcasting Corporation). No unusual behaviour to report (with the amp, that is). Tests will come later.
Attachments
You're right, Zen Mod. No Schade, although it is a single-ended BAF2015 design, so it's kind of appropriate.
..I listened for circa 2 hours. My impresssion in short words is:
in this configuration it seems to sound more 'precise'. This is the best word I can find for my impression. Especially in the mids and highs.
All the musical information appears - nothing is missing. Bass is really good and controlled. But the mid to highs seem to be more accurate/precise.
The other difference to me is the soundstage and impression of room has changed (seems downsized). It seems no more so 'airy' and completely 'uncoupled' from the loudspeakers anymore.
But these are first impressions. And I did not play at the settings of the B1 NUTUBE pre.
I have very similar experience with connection to CCS point D.
Amazing how little 0.1R resistor can make such audio perception difference.
🙂 Greetings
to Soundhappy #1110
Hello Soundhappy,
it's a great experience I have with this amp. Great chance Nelson Pass gave to us.
Thanks for your hints, Soundhappy!
The journey into sound continues.... 🙄
Greets
Dirk
Hello Soundhappy,
it's a great experience I have with this amp. Great chance Nelson Pass gave to us.
Thanks for your hints, Soundhappy!
The journey into sound continues.... 🙄
Greets
Dirk
..it's a great experience I have with this amp. Great chance Nelson Pass gave to us....The journey into sound continues.... 🙄
Any better sound if reversed or not reversed speakers polaritys with CCS at D connection ?
Very adjustable pre & power amp combo!
Thanks again to Mr. Pass for excellent BAF 2015 talk and tech documentation slides

Untested DRAFT PCB layout for comment. It will cost me the same to buy two boards as it will six, so I'll donate and ship two pairs to anyone interested in helping to prototype the hockey puck "sh*t amp."![]()
Hi
Some PCB Gerber file or PCB for Singing Bush AMP?
God bless
to alheiz #1115
Hello alheiz,
you will have to contact ZenMod. He made pcbs.
Change to his thread: The Singing Bush
The Singing Bush
Greets
Dirk
Hello alheiz,
you will have to contact ZenMod. He made pcbs.
Change to his thread: The Singing Bush
The Singing Bush
Greets
Dirk
Input Transformer Connections
Trying a p2p version of this amp. Can someone verify or maybe a picture of their transformer connections? I've gone through this thread 3-4 times now, and I've seen it different ways...slightly confused.
Thanks
and a few gratuitious hardware shots for the heavy metal folks
Trying a p2p version of this amp. Can someone verify or maybe a picture of their transformer connections? I've gone through this thread 3-4 times now, and I've seen it different ways...slightly confused.
Thanks
and a few gratuitious hardware shots for the heavy metal folks
Attachments
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