[danman]

Ok James. You would know so I won't send it in for nothing. I suppose that my Focals are by nature quite sensitive and I'm used to the ML's being around 85db at best!

The amp sounds great otherwise it is just I am not used to having speakers this easy to drive. I can barely put the volume past 9:00 and it is filling the room! The amp runs so much cooler too because the ML's take a lot of power as you know.

Thanks so I guess problem solved!

[mfau]

Hello Danman,

With a similar setup, I can hear an hiss as you describe.  4B SST2, BP-26, BDA, BCD, B&W 803D. System is 6 months old.  Volume at minimum, only amp on.  Audible hiss (noise) in tweeter with ear up to 12 inches apart, not from listening position.  I had Focal Diva Utopia Be as a loaner and the hiss was present.  I would prefer a dark-no sound at all at no volume, but as I don't ear it from listening position, it does not impact listening experience.

I must say I LOVE my system.  Incredible evenings listening to music with family and friends!  Sound, detail, dynamics are incredible.

Cheers,

Martin

[danman]

Thanks. I guess it is normal

[Phoenix]

I also think it's normal.
My speakers have 98 dB sensitivity and you can even hear the background noise from amps with 112 dB S/N ratio.

That's the price for having high efficiency speakers: You really need dead quiet electronics to have an adequately noise free background  - Bryston for example may be a good choice...

[Anonamemouse]

Likewise, it's only if I max out the volume and put my ear flat out against the speaker a hear a faint hiss or hum (whatever it's just too soft). At my listening position about 2.5m away I can't hear a thing...

If it is the Bryston amp that hisses it should always be audible, even when it is the ONLY thing that is on. A power amp that is on always amplifies, even without input signal.
The moment the hiss increases whenever something else is turned on and set to full volume, the hiss does NOT come from the Bryston amp, but from whatever was turned on.

I can hear an extremely faint hiss when i put my ear close (1 ft) to the tweeter, but this is not audible at my listening position. The only thing that increases the hiss here is my tuner. The rest is "hissfree".

[danman]

Nothing else in my system increases the hiss therefore it is only because of the speakers I would think.

[SoundGame]

I've resurrected this thread because I've discovered that my rather new 4B-SST2 (2 months old) has the exact problem as Danman described here.

When both my BP6 and sources are off and I power up my 4B-SST2 - I can hear a faint hiss (like white noise) from the tweeters of my Epos ELS3 speakers from 0" to about 12" away.  Can't be hear over natural ambient noise from any farther and definitely not from the listening position.  My ELS3 have the following specs:

Frequency range: 65Hz-20kHz. Impedance: 4 ohms nominal. Sensitivity: 87dB/W/m

So this can't be due to high sensitivity of the speakers, in my case. 

With the BP6 turned on there is no increase in the volume of this noise until the volume position goes past 12 o'clock, at which time the noise increases slighly in volumen - perhaps detectible from about 16" away.

Danman - did you get your concenrs resolved.  Can any others with 4B-SST or other Bryston amps attest to this white noise when within 1ft of the tweeter of your speakers with only the amp on?


Not sure this is worth a service call but it does make me curious what's causing this given that the noise floor on the 4B-sst2 is supposed to be very low.

[VOLKS]

I actually had the same problem with my Bryston 4BSST2/BP26/BCD-1 Combo as well.....a hiss that i could hear thru every source i tried......the irony for me was that when i sold the 4BSST2 and replaced it with a Mcintosh MC452 Amp thru the BP26  the hiss went away LOL...go figure    

[Stu Pitt]

I wonder if the hiss is caused by electrical lines, and the amps are just amplifying it?

[VOLKS]

I wondered that as well Stu......so i had my friend come over who is a certified electrician and he tested/went thru every line/plug in my house and nada-no noise in my lines........it was the strangest thing/gremlin

[James Tanner]

Hi sound game

Hiss can just be the thermal noise of the transistors and the total gain in the system

James

[Elizabeth]

The slight hiss I agree is thermal noise. The stuff of electrons and such.
I doubt if any setup has zero hiss.
Just some combinations make it a bit more distinct.
Zero to worry about IMO.
When you can hear it at the seated position, then you might wonder is something is up.
At a foot from a tweeter, that is like totally normal 100%.

[SoundGame]

Okay - sorry - just reverified some specifics, right now.

With the IC between the BP6 and 4B unhooked, so nothing hooked up to the 4B but the OEM power cord and my Kimber 4PR 8ft speaker cables to my ELS3's you can hear the startup softstart click as the amp powers on and then the hiss can be heard. 

I've measured more carefully, and the hiss can only be heard at about 4" to 6" away, with just the amp in play. 

When connecting the BP6 via the single ended 1ft AudioQuest Diamondback - no source on - when the BP6 clicks on the hiss does increase ever so slightly but I've now confirmed that it does not increase any further regardless of the volume position.  In other words, sweeping the volume from low to high makes absolutely no difference on the sound level. 

I did notice that moving even slighly closer or farther from the tweeter or slightly off direct axis, changes the ptich and volume that the hiss is heard at - this was what caused my earlier impression that the volume position was impacting the sound (confirmed that this is not the case).

Yes - this could be the inherent noise floor of the system I'm hearing - the electicity itself in flow.  Again, this can't be heard at 6" to 12" away and definitely not from the listening position.  I'm sure that much more effecient speakers may increase the distance at which it can be heard but we'd have to get soe Klipsh owners to share their impressions.

Volks - it could be that you don't hear the hiss on your McIntosh amps just becasue McIntosh is not as revealing - kind of like a filter they have added

[VOLKS]

I honestly have no idea soundgame,but I am very happy the hiss is gone.As a sidenote.......I also have tried Cary,Ayre,Grant Fidelity,Acoustic Arts and Moon amps that friends have let me borrow,before I bought my Mcintosh and guess what?All those brands had no hiss as well......so I don't know what to say.   As far as revealing  goes......trust me Mcintosh is easily as revealing as Bryston.....both are amazing well built,beautiful sounding amps.

[vegasdave]

I honestly have no idea soundgame,but I am very happy the hiss is gone.As a sidenote.......I also have tried Cary,Ayre,Grant Fidelity,Acoustic Arts and Moon amps that friends have let me borrow,before I bought my Mcintosh and guess what?All those brands had no hiss as well......so I don't know what to say.   As far as revealing  goes......trust me Mcintosh is easily as revealing as Bryston.....both are amazing well built,beautiful sounding amps.

Your testing methods are flawed.

[vegasdave]

Hi sound game

Hiss can just be the thermal noise of the transistors and the total gain in the system

James

Exactly.

[Anonamemouse]

I actually had the same problem with my Bryston 4BSST2/BP26/BCD-1 Combo as well.....a hiss that i could hear thru every source i tried......the irony for me was that when i sold the 4BSST2 and replaced it with a Mcintosh MC452 Amp thru the BP26  the hiss went away LOL...go figure

Before my current black 4B SST2 I had a silver one that hissed quite loud on one channel. Loud enough to hear from 3 feet away. My current 4B is dead quiet.
Me thinks this is something you might want to look into James... Too many people have a hiss...

[James Tanner]

Before my current black 4B SST2 I had a silver one that hissed quite loud on one channel. Loud enough to hear from 3 feet away. My current 4B is dead quiet.
Me thinks this is something you might want to look into James... Too many people have a hiss...

Every single amp is checked as it leaves Bryston for noise and distortion against a strict standard - we can certainly look at the amplifier for SoundGame but I doubt we will find an issue. Bryston amplifiers have higher internal gain than most amps and I am sure that is what is happening and it will act differently in different systems depending on overall gain characteristics within those systems.

james

[BrysTony]

Every single amp is checked as it leaves Bryston for noise and distortion against a strict standard - we can certainly look at the amplifier for SoundGame but I doubt we will find an issue. Bryston amplifiers have higher internal gain than most amps and I am sure that is what is happening and it will act differently in different systems depending on overall gain characteristics within those systems.

james

A few months ago I noticed a faint hiss which could only be heard within about 6 - 12 inches of the speaker.  I dismissed it since it could not be heard from the listening position.  Since that time I have rearranged my equipment in the rack and the hiss has completely disappeared.  My conclusion was that it probably had something to do with the routing of the cables -- perhaps an interconnect picking up some noise from a power cable.

Tony

[James Tanner]

A few months ago I noticed a faint hiss which could only be heard within about 6 - 12 inches of the speaker.  I dismissed it since it could not be heard from the listening position.  Since that time I have rearranged my equipment in the rack and the hiss has completely disappeared.  My conclusion was that it probably had something to do with the routing of the cables -- perhaps an interconnect picking up some noise from a power cable.

Tony

That's possible Tony as the Bryston amps are very wide bandwidth amplifiers - .5Hz to 130kHz. As a complete contrast tube amps are typically bandwidth limited due to their output transformers.

James