Hiss in active speakers

[JJB70]

There seems to be a bit of a recurrent theme of active speakers having audible hiss, including expensive ones. Given that the future may very well be active digital speakers and they do offer some attractive attributes is there any reason for there to be hiss? Is it poor design or is there a particular reason for active speakers to be susceptible to audible hiss? I have a pair of KEF active digital speakers which I love and do think that the concept of active speakers with a built-in DAC is the way forward but it seems odd that the issue of hiss seems to come up a lot.

 

[Purité Audio]

No hiss here, with Kii, Grimm and Dutch& Dutch.
Keith

 

[svart-hvitt]

Genelec state the self-generated noise in the specifications of all of their speakers.

I am not sure if they’re the only ones to state such noise?

Here is an example, from a brochure for The Ones speakers:

 

[Dialectic]

I've occasionally noticed the tiniest hint of hiss from my D&D 8Cs. It is barely noticeable with your head 10 inches from the tweeter and is inaudible from the listening position. Hiss in active speakers results from the direct connection of an amplifier to a tweeter, with no attenuating components in the circuit.

I have noticed small amounts of hiss from all active loudspeakers I've auditioned, usually only when I put my head next to the tweeter.

Unless one is listening in the very near field, I think the sonic benefits of active loudspeakers outweigh the drawback of hiss.

 

[JJB70]

I am an advocate of active speakers, but it is something I've noticed that many of them seem to suffer hiss to a degree, however minor. The KEF speakers I have suffer from it but I can't honestly say it is a distraction or noticeable when listening to music.

 

[sergeauckland]

Well designed active 'speakers don't have hiss any more than passive 'speakers in normal use. However, most tweeters and midrange drivers are generally more sensitive than bass drivers, so in a passive loudspeaker, they will be attenuated in the crossover, reducing any amplifier hiss. This doesn't happen with active 'speakers using similar drivers, so greater care has to be taken with amplifier hiss and especially noise from the electronic crossover.

As an example, my own bass driver has a sensitivity spec of 86dB/2.83v, whilst the midrange is 93dB and the tweeter 88dB, and I did have to get the noise well down to avoid problems.

S

 

[svart-hvitt]

I am an advocate of active speakers, but it is something I've noticed that many of them seem to suffer hiss to a degree, however minor. The KEF speakers I have suffer from it but I can't honestly say it is a distraction or noticeable when listening to music.

The hiss of well engineered speakers will not get amplified as you increase SPL volume. It will hence get masked by background noise at a distance or by the played back program material.

Is it an aesthetic problem? You bet!

 

[RayDunzl]

JBL LSR 308 hiss measures:

https://www.audiosciencereview.com/forum/index.php?threads/jbl-lsr-308-in-the-house.1066/#post-27832

 

[DDF]

https://www.audiosciencereview.com/...w-of-dutch-dutch’s-8c.7308/page-2#post-168558

 

[Jaimo]

To hear any hiss, I have to pretty much stick my ear into the waveguide of my JBL LSR708P’s. I have the speaker gain turned up to max.

Not an issue from more than a few feet away.

 

[solderdude]

Hiss is the main reason I did not buy the LSR305 as monitor speakers for my PC.
Maybe it was the gear connected to it but as JJB70 mentioned it isn't needed in this day and age.
Considering I have about 7dB hearing loss (age related) in the 'treble range'.
I could hear it hiss (faintly) in the shop at 0.5m, the distance where I would be using them.
A colleague has them in his home studio. Will visit him and check there.
The Dynaudio actives I demoed at the same shop did not have any audible hiss at all and sounded better but were too expensive.
Ended up using small Dali passives + refurbished and modified Quad 33+303 as I had that lying around. No audible noise at 0 volume.

 

[restorer-john]

I think some people are more sensitive to 'hiss' that others. I'm one who can't stand hiss.

I spent my younger years trying to get it down to levels where it didn't matter in the cassette days, Dolby C, dbx, HiFi VHS recorders and then DAT. It wasn't until DAT where hiss was truly gone.

CD players highlighted the deficiencies of amplification up to that point, and much effort was put in by manufacturers to get as much active (noise producing) stages out of the amplification chain. Now we are adding A/D-D/A stages, DSP and directly coupled drivers to Class D amplifiers all shoved in a box. No wonder hiss has reared its ugly head again. Consider outside the ridiculously loud demonstrations dealers will do to show you what these powered marvels can achieve, most of the time signal levels will be much lower and rooms will be quiet. Do you want to hear hiss? I sure don't, and certainly not for the money they seem to sell for.

I can often hear tweeter hiss across demo rooms with passive speakers. I can hear hiss in active speakers across the room when it's quiet. There's not a subwoofer I own (I think I have maybe a dozen) where I can't hear the amplifier residual noise, even with a shorted input.

I have some (3 identical ones) >105dB S/N rated Sony ES preamplifiers with a rated residual <10uV (A Wtd) where I love their performance and sound, but they have a hiss I can hear on the line stages. I have to pad down the power amps so I don't hear that hiss.

I want to see A Wtd residual noise over the audible bandwidth numbers in uV specified for amplifiers, preamplifiers and any digital devices. Not best case numbers either. Worst case.

 

[solderdude]

I think some people are more sensitive to 'hiss' that others. I'm one who can't stand hiss.

I can't stand hiss and hum.
I too have experienced that I am more 'triggered' by this than others for the same reason (trying hard to get rid of it in younger years ?) and appear to have developed a sensitivity for it.
As an example ... I can hear the fridge run when in the kitchen and also the water-fountain for the cats and even switch the fountain off when I have to be there for a certain period. The rest of the family can hear it as well but aren't bothered by it.

Also hate severe resonances when in certain freq. ranges.

 

[JJB70]

I think that it is an aspect of active speakers that needs further work. I guess I am of an age like Restorer John whereby I can remember just how great we considered it when hiss was eliminated. True, the hiss of my Kef speakers doesn't bother me when listening to music but they cost me £240 and are in my home office. If I was to buy a pair of active speakers for my main listening room and was considering something nice then I would be less sanguine. It's a bit like having a scuff on a car that will normally not be obvious, knowing it is there is annoying. My current system is over 25 years old and I don't have any audible hiss. And yet if I was replacing it I would favour system speakers if there are models which have beaten the hiss.

 

[oivavoi]

I'm also rather sensitive to hiss. We're now on our third fridge in six months, in the ongoing search for a completely quiet fridge... The wife doesn't notice at all and thinks I'm crazy.

My trusted ol' active AVI sprakers don't have any hiss at all. That is when using a sensible gain setting, which means max gain from source/preamp, and lowering gain on the speakers accordingly. But their crossover is an old-fashioned active analogue crossover, not a digital/electronic crossover. I wonder if it's the digital crossover that is the main culprit usually? Have not heard any complaints about hiss about the venerable analogue ATC actives either, for example.

 

[restorer-john]

We're now on our third fridge in six months, in the ongoing search for a completely quiet fridge...

We bought a Samsung 460L fridge recently and its incredibly quiet. Clearly it must be running an inverter powered compressor that can ramp up and down. I honestly couldn't believe how quiet it is compared to our old one. There is no clear switch on and off, it is gradual and gentle. The most noise is the occasional tiny sounds from the frost free element melting ice on the coils, but that is rare to hear.

 

[Soniclife]

We bought a Samsung 460L fridge recently and its incredibly quiet. Clearly it must be running an inverter powered compressor that can ramp up and down. I honestly couldn't believe how quiet it is compared to our old one. There is no clear switch on and off, it is gradual and gentle. The most noise is the occasional tiny sounds from the frost free element melting ice on the coils, but that is rare to hear.

Our 2 year old Samsung fridge is a lot quieter than the fridge that replaced it, and very nearly quiet enough all the time, I rarely notice it, where as I noticed the old one all the time. I'm only concerned with how it sounds outside the kitchen, I'm ok with hearing it making noise in the kitchen, it would still annoy me if our house was open plan.

 

[Frank Dernie]

The only active speakers I own are Devialet Silver Phantoms. They are completely silent. The only way to tell if they are on is to touch the heat sink at the back which are slightly warmer than ambient when they are on.

 

[svart-hvitt]

I think some people are more sensitive to 'hiss' that others. I'm one who can't stand hiss.

I spent my younger years trying to get it down to levels where it didn't matter in the cassette days, Dolby C, dbx, HiFi VHS recorders and then DAT. It wasn't until DAT where hiss was truly gone.

CD players highlighted the deficiencies of amplification up to that point, and much effort was put in by manufacturers to get as much active (noise producing) stages out of the amplification chain. Now we are adding A/D-D/A stages, DSP and directly coupled drivers to Class D amplifiers all shoved in a box. No wonder hiss has reared its ugly head again. Consider outside the ridiculously loud demonstrations dealers will do to show you what these powered marvels can achieve, most of the time signal levels will be much lower and rooms will be quiet. Do you want to hear hiss? I sure don't, and certainly not for the money they seem to sell for.

I can often hear tweeter hiss across demo rooms with passive speakers. I can hear hiss in active speakers across the room when it's quiet. There's not a subwoofer I own (I think I have maybe a dozen) where I can't hear the amplifier residual noise, even with a shorted input.

I have some (3 identical ones) >105dB S/N rated Sony ES preamplifiers with a rated residual <10uV (A Wtd) where I love their performance and sound, but they have a hiss I can hear on the line stages. I have to pad down the power amps so I don't hear that hiss.

I want to see A Wtd residual noise over the audible bandwidth numbers in uV specified for amplifiers, preamplifiers and any digital devices. Not best case numbers either. Worst case.

I wondered: If the hiss is measured at 5 dB at 1 meter, when will the speaker’s self-generated noise be inaudible or masked by ambient noise depending on:

1) Ambient noise level
and
2) Distance from speaker?

 

[svart-hvitt]

ME Geithain is another serious producer who states the inherent self-generated noise in their speakers.

The top-of-the-lines 801k and 811k have 10 and 7 dB of inherent noise at 1 meter:

https://www.me-geithain.de/en/rl-801k-11.html

https://www.me-geithain.de/en/ml-811k1111.html