Music First Audio Passive Magnetic Preamplifiers?

N37000, if those are still available, that is an AWESOME price and I would suggest people jump all over it :). I have sent a question to MFA concerning your' points, however, I think MFA is the finished product line entity if you will of S&B. I also am pretty sure they stopped selling their transformers to other parties.

I will update this thread with the answers I receive from MFA but thanks for the info :)

I believe S&B stopped selling the transformers for DIY and OEM purposes a while back, which prompted John Chapman of Bent Audio to switch to the Slagle autoformers for his magnetic passive preamps.

Clio09 i believe you are correct air oall points. Here is the response I received from Harry at MFA/S&B in response to N37000's post;

Thank you for your message.
 
Yes, the S&B TVCU is still available. This uses a more basic transformer than the TX102 used in the MFA Classic Preamplifier, but it's performance is still very good. We also offer this with the TX102 transformer upgrade at £1100.00 GBP.
 
We do not supply our TX102 transformers to any other other companies and we have not done so for at least five years. Therefore, either this person is mistaken or the transformers are not genuine.
 
I hope this helps.
 
Many thanks and very best regards
 
Harry

Agear it is pretty cool that we ran nearly the same comparisons with some fairly esoteric gear. What variant of the Concert Fidelity were you listening to and where did you perform the testing with the 3 units ARC Anniversary, Concert Fidelity and TRL? 

What we heard with these units vs the GTP4 did not leave much room for interpretation. It (GTP4) simply fell by the wayside, so i find it all the more iteresting that you say the mid level preamp was better than the CF and the ARC. 

Interestingly enough, if memory serves, i liked my former GTP2 (when paul used 3 paralleled 6sn7 tubes per channel) more than the GTP4 which I am pretty sure is using the 6AS7 tubes.

I found that Pre (GTP4) to be a bit soft and lacking in weight and force. Interestingly I noted a lack of transient or leading edge snap with the GTP4. I say interesting because it lends creedance to something written by Bruce Rozenblit of Transcendent Audio fame in which he described his NOT choosing that particular tube (6AS7) for his OTL amps for that very reason. He stated that with the 6AS7 he found it lacked the ability to produce the leading edge transient satisfactorily quote, "Tests were run with the 6AS7 and it was found to be unable to produce the sharp transient attack required for the best performance". 

Now having written this, I have not heard the ~5k Dude and i have no idea what tube compliment it uses. Perhaps it is better than the GTP4.., but for roughly $30k less it probably should not be :)

Best regards

I have the Bent Tap X, and it is one of the most transparent passive I have heard with flexibility no other passive can match. It was about $2000 USD for the 6 input version. It still doesn't beat going directly from my DAC to amp, but gets it pretty close. Too bad it is now out of production.