[Moon Doggy]

I'm thinking of purchasing a Bryston Amp. Probably the 2B or 3B SST Squared. My pre-amp can be set as passive or active in steps of 3, 6, or 9 dB. Are the Bryston amps sensitive enough to be run by a passive pre? Even if they are able to be run by a passive pre would I get better sound with one of the other settings? Thanks.

Regards, James

[James Tanner]

I'm thinking of purchasing a Bryston Amp. Probably the 2B or 3B SST Squared. My pre-amp can be set as passive or active in steps of 3, 6, or 9 dB. Are the Bryston amps sensitive enough to be run by a passive pre? Even if they are able to be run by a passive pre would I get better sound with one of the other settings? Thanks.

Regards, James

Hi James,

The 2B SST has a sensitivity of 1 Volt and the 3B SST is 1.3 Volts.

james

[Moon Doggy]

I'm thinking of purchasing a Bryston Amp. Probably the 2B or 3B SST Squared. My pre-amp can be set as passive or active in steps of 3, 6, or 9 dB. Are the Bryston amps sensitive enough to be run by a passive pre? Even if they are able to be run by a passive pre would I get better sound with one of the other settings? Thanks.

Regards, James

Hi James,

The 2B SST has a sensitivity of 1 Volt and the 3B SST is 1.3 Volts.

james

Hi James,
      Thanks for the response. Given that the 2B SST and the 3B SST have input sensitivities of 1V and 1.3V respectively. And that a passive pre-amp adds no gain. I would look to the outputs of my sources. My phono pre has a Maximum Output (1kHz @ 10k ohms)    3.0 Volts and I know my CD player has a big power supply and is louder than my phono source thru an amp. So would it be safe to run the pre in a passive setting if I set the input sensitivity switch on the back of the 2B SST or 3B SST to 1V input and a gain of 6dB? Thanks for any help as I'm new to these facts and figures.

 Cheers, James

[James Tanner]

HI James,

Yes you should be OK with the passive - most CD Players output around 2volts.
That being said using a Passive preamp can be problematic so make sure you use very short interconnect cables and preferably low capacitance.

Passive pramps are a whole subject on their own. I have been seduce myself by passive preamps and although common sense would advocate - "no electronics makes more sense than some electronics" - I have always found that although passive preamps can sound very smooth they seem to lack the dynamic capabilities (micro and macro) of a good active preamp. My guess is that there are just a large number of variables that have to be taken into account when using a passive preamp - cable issues, impedance issues, loading issues and voltage swing issues to name a few.

james

[Moon Doggy]

James... Thanks for the feedback. Its good to know that I should be alright with my pre-amp. Good to learn of some of the problems that might surface as well. My dealer also mentioned that there can be a trade off between smoothness and dynamics when running a passive setup. I've only heard one Bryston amp and it was very dynamic so the smoothness introduced by the passive should be acceptable. Will demo the two together as soon as I have the time! 

Cheers, James