Pass BA-3 preamp (front end)

[anilva]

Folks,

Recently completed building a Pass BA-3 front end preamp. This is a part of the Burning Amp series of designs from Nelson Pass and people found this front end to be a terrific preamp. This has no feedback and can be adjusted to a mix 2nd order or 3rd harmonic content to sound warm or otherwise.

Sounds amazing when I coupled it with Pass F6. Is better couple of notches than a B1.

This preamp has loads of gain and also strong current drive capabilities, unlike the B1 which is a unity gain buffer.

The PCB is available at online store of diyaudio.com

Schematic and build guide are on diyaudio.com

Attached is the picture of the populated PCB along with a dual rail power supply board. I have removed the B1 from it's chassis and replaced with BA3.

I will highly recommend this build to you guys.

Cheers.

 

[Anil kumar]

Thanks for the feedback Anil, saw this on diyaudio recently. Love to listen.


Regards,
Anil

 

[shafic]

Thanks Anil, looks impressive. I am looking for a good preamp for my McIntosh. Pls suggest.
Regds,
Shafic

 

[anilva]

Thanks Anil, looks impressive. I am looking for a good preamp for my McIntosh. Pls suggest.
Regds,
Shafic

Currently from a preamp perspective, IMHO the BA-3 is top of the heap. Even many people on diyaudio believe so.

Cheers

 

[anilva]

This design is actually a F5 amp of Pass without feedback and lower bias.

Cheers.

 

[manniraj]

This design is actually a F5 amp of Pass without feedback and lower bias.

Cheers.

Is it a straight forward plug and play by removing the B1 or DCB1 from the chassis and replacing with BA-3. As we already have the dual power supply so I believe the PSU which you listed is not specifically for BA-3 right! As this can also be used for preamp then we can replace the SSP+B1 with this in the chain right?

 

[anilva]

Is it a straight forward plug and play by removing the B1 or DCB1 from the chassis and replacing with BA-3. As we already have the dual power supply so I believe the PSU which you listed is not specifically for BA-3 right! As this can also be used for preamp then we can replace the SSP+B1 with this in the chain right?

Nothing changes, except the power supply is +/- 24v. Any good regulated PS will do.

Cheers.

 

[manniraj]

Nothing changes, except the power supply is +/- 24v. Any good regulated PS will do.

Cheers.

Thanks Anil, do you have the part list as well.

 

[anilva]

It is available in the thread "BA3 preamp build guide" by 6L6 at Diyaudio.com

Regards

 

[Fantastic]

Is it possible for you to do a test with and without the preamp, direct into the power amp ? What changes did you notice, if you have tried this.
Cheers.

 

[anilva]

I simply cannot do away with a preamp (active or passive) because of a complex active setup. Hence I have not tried without a preamp on this setup.

Cheers.

 

[captrajesh]

Currently from a preamp perspective, IMHO the BA-3 is top of the heap. Even many people on diyaudio believe so.

Interesting! Wonder how does it compare with the DCB1 or the Kuartlotron Error Correcting Super Buffer!

I think FM Manniraj made one recently. Hope you would find some time to do a one-on-one comparo with it and post the results.

 

[sathiamoorthy]

I think FM Manniraj made one recently. Hope you would find some time to do a one-on-one comparo with it and post the results.

I wish this happens. It will be interesting.