[KnowTalent]

RANT: My one MAJOR complaint about my (otherwise wonderful) Bryston BP-26 and Bryston 4B-SST2 pairing is the stupid low volume setting when using a CD (either DAC OR CD player.) When I use the phono (Bryston 1.5) the volume is a comfortable 11 O'Clock to 2 O'Clock position. (and 2 O'Clock is as loud as I would ever, ever put it.
With CD the volume control is a disgusting 7 O'Clock to 8 O'Clock max!!! that just sucks. I mean it STARTS at 7 O'Clock position.
Since I started using a 'VAC Standard' preamp as just a tube buffer for only the digital I do not have a problem, as the VAC volume in combo with the Bryston BP-26 gives both a position of around 9 O'Clock to 10 O'Clock.
(Before i got the VAC I had to stick my old Adcom preamp into the chain at the amp in passive mod JUST to use it's volume control to allow me to use more of the range of my Bryston BP-26. and I got a LOT of heckling from the "moron: we know it all and better than you" crowd for having two preamps daisychained.. I tell you.)
The Bryston BP-26 SHOULD have a SOME inputs with less gain. OR the BP-26 could be factory built with LESS gain as an option, or could be sent in to get less gain as an option.
When I cannot use the volume beyond 8 O'Clock it is annoying, really.
Before The stupid CD standard of FOUR times normal volts of other input devices... I am certain the Brystons were perfect concerning gain. But WITH the CD standard, and the fact many companies are going even higher than 2V in output from CD/DAC devices... I don't know..

I don't understand this either although it would seem logical to design an amp with a higher input sensitivity to allow running the volume control on the pre at the top of it's range where the SNR is greatest.  Seems counterproductive to pay $$$ for a clean/quiet pre and then not get the full benefits of the circuit design by virtue of running the volume setting in its lower range where SNR can be down 20-30db.  I don't know how big a difference it ultimately makes but still I ask why?

[BrysTony]

There are a lot of variables that affect the volume control setting for a given preamp/amp combination. 

1.  Source Material: Older CDs were recorded at lower average levels than the newer compressed CDs.  Vinyl depending on the cartridge and the phono stage often require higher volume settings.

2.  Speaker Efficiency

3.  Room Size

4.  Individual preferences on sound level.  (My GF likes lower volume than I do.)

My BP26 volume setting varies between 8 and 1 O'Clock depending on variables 1 and 4 above.

Tony

[KnowTalent]

There are a lot of variables that affect the volume control setting for a given preamp/amp combination. 

1.  Source Material: Older CDs were recorded at lower average levels than the newer compressed CDs.  Vinyl depending on the cartridge and the phono stage often require higher volume settings.

2.  Speaker Efficiency

3.  Room Size

4.  Individual preferences on sound level.  (My GF likes lower volume than I do.)

My BP26 volume setting varies between 8 and 1 O'Clock depending on variables 1 and 4 above.

Tony

Yes, but you'd be getting better SNR if your minimum listening level was noon on the dial... running up to perhaps 3 or 4 O'clock for louder listening.

I guess one could always switch to 82db efficient speakers to achieve this
creating system synergy can be a real chore

[vegasdave]

There are a lot of variables that affect the volume control setting for a given preamp/amp combination. 

1.  Source Material: Older CDs were recorded at lower average levels than the newer compressed CDs.  Vinyl depending on the cartridge and the phono stage often require higher volume settings.

2.  Speaker Efficiency

3.  Room Size

4.  Individual preferences on sound level.  (My GF likes lower volume than I do.)

My BP26 volume setting varies between 8 and 1 O'Clock depending on variables 1 and 4 above.

Tony

Exactly. You nailed it.

[NewBuyer]

...I am just trying to understand why so many amp manufacturers build amps with such low V sensitivities when much of the "high end" sources have relatively "hot" outputs...

I personally agree with KT on this sentiment.  Good amps with higher-voltage input sensitivities would be a very welcome thing.  This would clearly allow you to better maximize SNR/dynamic-range, e.g. as is the common approach in the pro-audio setting.  But it would also go against the grain of current consumer audio marketing, as most consumers have been led to think 'more watts' = 'better sound' these days.

I think that many consumers probably use less than 20 amp watts (including peaks) during nearly all of their listening, with various exceptions including those with inefficient systems, those that are deaf, and/or those who are extremely inconsiderate to any close-by neighbors.    However, just try to find a really good balanced 20W solidstate amp with an input sensitivity of around 2-volts!  (Seriously - If you know of one, feel free to mention it?)

Having analog input attenuators built right onto the amp (like Parasound does, along with most pro-audio amps including the Bryston amps from the pro-audio side), can help a lot with this issue as well.

Or you could switch to 82db (or less) efficient speakers!  But I bet they won't sound very good, relatively speaking.  Or, you could just give-in and let yourself go deaf! 

[Napalm]

[...]
I think that many consumers probably use less than 20 amp watts (including peaks) during nearly all of their listening, with various exceptions including those with inefficient systems, those that are deaf, and/or those who are extremely inconsiderate to any close-by neighbors.  [...]

I've been pondering for a while now on the acoustic well being of my neighbors. However I think I'll wait first for them to stop walking their dogs on my lawn before I reconsider the default position of my volume knob.

Nap.

[KnowTalent]

Having analog input attenuators built right onto the amp (like Parasound does, along with most pro-audio amps including the Bryston amps from the pro-audio side), can help a lot with this issue as well.

Yeah, but unfortunately Parasound's amps gaing setting maxes out at 1V sensitivity...something about getting a THX rating perhaps(?)

Bryston lists either 1V or 2V (switchable) and I'm confused if that is for single-ended operation OR balanced.  Would those numbers translate to 2V or 4V via balanced inputs????
I'll wait to see what Chris comes back with on this.

[James Tanner]

Yeah, but unfortunately Parasound's amps gaing setting maxes out at 1V sensitivity...something about getting a THX rating perhaps(?)

Bryston lists either 1V or 2V (switchable) and I'm confused if that is for single-ended operation OR balanced.  Would those numbers translate to 2V or 4V via balanced inputs????
I'll wait to see what Chris comes back with on this.

Hi,

Chris should be back next week but the 1 volt and 2 volt settings are designed so that the 1V setting is generally used with Single ended (RCA) and the 2 Volt setting with Balanced XLR - but you can use it either way depending on the overall gain in the system. 

The sensitivity of the amplifiers is based on... 1 volt in equals 100 watts out.

james

[1oldguy]

I personally agree with KT on this sentiment.  Good amps with higher-voltage input sensitivities would be a very welcome thing.  This would clearly allow you to better maximize SNR/dynamic-range, e.g. as is the common approach in the pro-audio setting.  But it would also go against the grain of current consumer audio marketing, as most consumers have been led to think 'more watts' = 'better sound' these days.

I think that many consumers probably use less than 20 amp watts (including peaks) during nearly all of their listening, with various exceptions including those with inefficient systems, those that are deaf, and/or those who are extremely inconsiderate to any close-by neighbors.    However, just try to find a really good balanced 20W solidstate amp with an input sensitivity of around 2-volts!  (Seriously - If you know of one, feel free to mention it?)

Having analog input attenuators built right onto the amp (like Parasound does, along with most pro-audio amps including the Bryston amps from the pro-audio side), can help a lot with this issue as well.

Or you could switch to 82db (or less) efficient speakers!  But I bet they won't sound very good, relatively speaking.  Or, you could just give-in and let yourself go deaf! 

So the Pro version do have a benefit over the consumer versions in this regard?

[James Tanner]

So the Pro version do have a benefit over the consumer versions in this regard?

You can adjust the pro version down to a gain of 13dB (fully anti-clockwise)  if you wish.

james

[1oldguy]

You can adjust the pro version down to a gain of 13dB (fully anti-clockwise)  if you wish.

james

Wondering how this would help with what others here are talking about when using the balanced outputs on the BCD-1?

[KnowTalent]

You can adjust the pro version down to a gain of 13dB (fully anti-clockwise)  if you wish.

james

I overlooked this on your website as the only place I found mention of it was the listing of back panel switches in the owners manual.

How much does a pro model retail for vs. a "standard" 4B SST2?

[James Tanner]

I overlooked this on your website as the only place I found mention of it was the listing of back panel switches in the owners manual.

How much does a pro model retail for vs. a "standard" 4B SST2?

Hi KnowTalent,

Same price just the Pro unit is only available in Black 19 inch rackmount faceplate.

james

[Elizabeth]

James,
If I wanted my consumer version (black rack mount faceplate) 4B-SST2 changed to have just that extra attenuation available (from the US service certer) can I? and how much would it cost?
If it would let me use more of the volume control range of my Bryston BP-26 I would be much happier.

[James Tanner]

Hi Elizabeth,

Contact Mike Pickett at bryston and he would be able to give you a price.
mpickett@bryston.com

james

[vegasdave]

I overlooked this on your website as the only place I found mention of it was the listing of back panel switches in the owners manual.

How much does a pro model retail for vs. a "standard" 4B SST2?

You can get a healthier discount from a pro audio dealer. That's where I got my 4BSST from.

[James Tanner]

Hi James;
 
The sensitivity rating of amplifiers is stated differently from the output rating on a DAC or CD player.  When an amplifier specification is stated at 1V, it means that amplifier reaches 100W output at an input level of 1V RMS.  A DAC or CD player's output is rated at 0dB, or the absolute maximum peak output the player or DAC can provide. Musical levels will average in the range of at least 20dB below that outut level. Thus, in the case of  Bryston's BCD-1 or DAC-1 this average will be something in the range of 0.23V, or less than 1/4 of a Volt. Adding to that, most preamps including Bryston's, operate at a gain level that delivers the full output of the source at a Volume Control position of 12:00 on the dial.
 
If that gain setting seems too high, the amplifier may be operated at a setting of 2V sensitivity, (or 2V in equals 100W output).  This will yield a further decrease of 6dB in the system gain, so that it will require advancing the Volume Control to approximately 2:00 o'clock for the same loudness level. That will in turn provide about another 6dB in the system S/N ratio.  We find that this setting works very well in most systems, providing the user with something of a buffer against accidentally setting the volume too high for comfort, and giving a superb S/N ratio, although some listeners actually prefer the volume control to act a bit more 'aggressively' for their musical tastes.
 
I hope the above is helpful, but please let me know if you have any other questions.  Thanks for your interest!
 
Sincerely,
Chris Russell
Bryston Ltd.

[Napalm]

Kudos to Chris for a very clear explanation.

Nap. 

[KnowTalent]

Hi James;
 
The sensitivity rating of amplifiers is stated differently from the output rating on a DAC or CD player.  When an amplifier specification is stated at 1V, it means that amplifier reaches 100W output at an input level of 1V RMS.  A DAC or CD player's output is rated at 0dB, or the absolute maximum peak output the player or DAC can provide. Musical levels will average in the range of at least 20dB below that outut level. Thus, in the case of  Bryston's BCD-1 or DAC-1 this average will be something in the range of 0.23V, or less than 1/4 of a Volt. Adding to that, most preamps including Bryston's, operate at a gain level that delivers the full output of the source at a Volume Control position of 12:00 on the dial.
 
If that gain setting seems too high, the amplifier may be operated at a setting of 2V sensitivity, (or 2V in equals 100W output).  This will yield a further decrease of 6dB in the system gain, so that it will require advancing the Volume Control to approximately 2:00 o'clock for the same loudness level. That will in turn provide about another 6dB in the system S/N ratio.  We find that this setting works very well in most systems, providing the user with something of a buffer against accidentally setting the volume too high for comfort, and giving a superb S/N ratio, although some listeners actually prefer the volume control to act a bit more 'aggressively' for their musical tastes.
 
I hope the above is helpful, but please let me know if you have any other questions.  Thanks for your interest!
 
Sincerely,
Chris Russell
Bryston Ltd.

So if you're running the BCD/BDA balanced outputs through a preamp (at unity gain vol setting) the amp will be seeing ~ 0.5V at the input ("on average" based upon -18 db with a 4V max output)???
If this is so I can understand why the 2V input sensitivity should be plenty to give more volume range.

Peeling the onion further in an attempt to better understand system synergy...two more questions

You mention the 12 o'clock volume setting delivering max source output..therefore does the 12 o'clock volume setting on the preamp correspond with the highest SNR, best channel sep, etc...the preamp is capable of and/ or rated at?

For the BP26, your spec sheet calls SNR -103 db at 1V balanced input...so if the average input voltage to the pre is only 0.5V balanced ...how many db SNR are you giving up?

[Elizabeth]

Interesting.. no mention of speaker sensitivity. IMO a glaring omission. However I use Maggies (3.6)and at 85 dB the are still not allowing me to use my BP-26 and 4B-SST2 above 8 O'Clock volume with a CD input. I use the 1.5 and can get up to the 12 O'Clock position. So I have to say the 'theoretical' explaination just does not cut it in the real world for CD.
Sorry, but it does nothing for my problem, and no reply to my email  to your dude, James.