[NewBuyer]

Hello James (and other experts here),

Do Bryston amps use any form of choke regulation, and why/why not?  Is there any real benefit from it?

I ask this because I've seen choke regulation advertised elsewhere as a superior feature (Musical Fidelity advertises dual mono choke-regulated power supplies in some of their amps for example).  

Quoted from a review: "The idea of a choke is to filter the ripple that comes from the power supply when it charges the capacitors at the top and bottom of the sinewave.  This ripple is created when the rectifier diodes connect and disconnect to and from the grid; but also during this connection period noise on the mains supply can make its way into your component, and again a correctly rated choke filtration system will prevent the ripples and mains-borne noise from degrading the performance of the component."

Please enlighten?  Thank you in advance...

[James Tanner]

Hi NewBuyer;

Thanks for your inquiry about Bryston amps. Yes, our amps do have filtering to block any DC on the power line from entering the power-supply.  This is a must, as it can cause noise in the transformers.  The main source of offset in the power line is second harmonic from poorly designed power supplies in other equipment, and amplifier manufacturers are forced to contend with this by filtering the line.

I hope the above is helpful, but please let me know if you have any other questions. Thanks for your interest in Bryston.

Sincerely,
Chris Russell

[NewBuyer]

Hi, thanks for your reply, but I think you may have answered a different question here by accident, yes?

[NewBuyer]

James Tanner, Chris Russell, are either of you still there?  I am still wondering about the original questions please:

Does Bryston use choke regulation in any of their consumer amps?  What advantages would it provide?

 

[Sebastiaan de Vries]

Dear,

So far I know from the schematic's, No! Choke regulation is a methode you see a lot in Tube amplifiers. Musical Fidelity is an exception they use choke regulation almost everywhere

The DC blocking scheme in the mains input of Bryston amp's is even more impressive. Not al amplifiers have that. PS audio sell this kind of circuits seperate. Bryston use regulation in the voltage gain stages off the amplifiers.

Kind Regards,
Bas

James Tanner, Chris Russell, are either of you still there?  I am still wondering about the original questions please:

Does Bryston use choke regulation in any of their consumer amps?  What advantages would it provide?

 

[James Tanner]

Hi NewBuyer;

   Thanks for your inquiry re choke regulation, sorry for the delay in answering. Choke filtering is one useful way to reduce RF and HF contamination in power-supplies, as is capacitive filtering and straight DC regulation.  In order to preserve the low output impedance and high instantaneous current handling of the main power-supplies in our power amplifiers, we tend to use capacitive filtering and DC regulation in those products.  Our amplifier power- supplies tend to have RF and noise rejection in the -120dB range, so we know the filters are doing an excellent job.

  We do use chokes and pi filtering in the power-supplies on some of our audio processing equipment, ewhere the current draw tends to be steady and non-fluctuating.  That tends to be where they do the best job.

   Bryston will be representing some new technology in Power Line Conditioning in the near future, that has an element of choke filtering at high current levels.  Watch Bryston's website, <www.bryston.ca>, for more news in a few months.

   Thanks for your interest in Bryston audio components.  
Please let me know if you have any other questions.

Sincerely,
Chris Russell
Bryston Ltd.