WHY oh WHY do monitors have hiss?!?

[Head_Unit]

I mean it seems there are a lot of low-noise amplifiers out there-or am I conflating SINAD with raw output noise? (Well, I know I am, they are not the same thing, but am I crazy many amps are super quiet?). Yet I read SO many comments about hiss from monitors, not always cheap ones. Cost-cutting? Something about gain levels?

What the hell, this is 2026, I do NOT get it. And I do NOT get how any professional would find any level of hiss acceptable at all.

???

 

[Mnyb]

Most amp are speced with signal to noise ratio, not many spec absolute noise levels ,

Monitors you often sit closer.

The treble and midrange can be padded down with a resistor in a passive designs as they are usually much more sensitive than the bass drivers hence if you remove 10dB from the tweeter you also remove 10dB of noise from the tweeter.

Gain structure plays a big part if your monitor have a sensitivity pot or level control, you should turn it down as much as full volume from your source gives about the max loudness you ever want . You don’t want to amplify incoming noise .

That said amp quality varies in actives. My KEF LS60 are very quiet for example I don’t find them worse than any passive + amp combo I owned ?

But it’s tempting to skimp on the amps in active speakers as they often have a very limited scope, they should only drive one driver with no complex filter, so it can be speced closer to the needs , distortion is probably masked by the drivers but noise levels can be a tell tale?

 

[3125b]

Well, I know I am, they are not the same thing, but am I crazy many amps are super quiet?)

Well, yes - you've kinda go two compounding issues.
Low-noise amps are more difficult to design and more expensive to implement than just putting something together.
And active speakers do not profit from the attenuation of a passive crossover for the tweeter.

Noisy active speakers are something I can't stand for my use, but then again, I use them as computer speakers where a lot of the time I'm not listening to anything and thus the noise really stands out.
And it must be said that there are still many effectively silent active speakers, even fairly cheap ones.
My Focal Alpha Evo for example are inaudible from anything more than 10cm, compared to my current KEF R5 driven by a SMSL DA-9 (fairly average chipamp in terms of noise performance) are audible from no more than 5cm. That doesn't really make a difference.

 

[TurtlePaul]

An 90 dB signal-to-noise @ 5 watt amp will have about 83 dB SNR @ 1 watt. Connect that to a 93 dB / 1 watt @ 1 meter sensitive tweeter with no padding resistors and sitting at 1 meter you will have 10 dB self noise.

 

[DVDdoug]

get how any professional would find any level of hiss acceptable at all.

There is always SOME noise from all active analog electronics and it's not unusual for it to be audible a few inches from the tweeter. Noise audibility also depends on other ambient noise in the room.

Theoretically, active monitors don't have to be worse than an amp and passive speakers. Attenuation from a crossover could be one explanation but lowering the gain from the tweeter amplifier in a monitor should also lower the hiss. (The crossovers in my passive speakers don't have any tweeter attenuation.)

-or am I conflating SINAD

There are different ways of measuring SINAD and a bigger "S" (signal) gives you a bigger measurement. Noise is virtually never a problem with a strong signal but it can be an issue at low levels or during silence. It's possible to measure the SPL level of the noise (with no signal) but I don't think I've ever seen that in the specs.

 

[staticV3]

Without a passive crossover to pad it down, a tweeter mounted in a waveguide can easily exceed 100dB SPL/2.83V sensitivity.

Power it from a typical chip Amp like the TAS5613A with 185μVrms of A-wt self-noise and you get 100+20*log10(.000185/2.83)=16dB SPL @1m.

Sure you could spend some $20-50 more on a quieter Amp and tack an extra $50-100 onto the MSRP, but you will lose way more sales to the increased MSRP, than you would gain from the reduced self-noise which is difficult to communicate/market anyway.

 

[Penelinfi]

I feel there's something to do with the way active monitor amps seem to be implemented. It's like running the amp wide open; PC noise comes through readily, whereas on a "normal" amp with volume control, that noise gets turned down with turning down the volume control.
Of course there is the real self noise which cannot be turned down. Things built for robust, more power, maybe cheaper, have more noise along with efficient drivers that play that noise louder at idle

 

[ZolaIII]

It's amp SINAD to speakers sensitivity regarding self noise. Many reasons for such behaviour and all cost related. On; I/O side, on driver side not only power amplifier side. ADC and tweater sensitivity the most only then not so great amps.

 

[Timcognito]

RFI and EMI

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[popej]

Without a passive crossover to pad it down, a tweeter mounted in a waveguide can easily exceed 100dB SPL/2.83V sensitivity.

Power it from a typical chip Amp like the TAS5613A with 185μVrms of A-wt self-noise and you get 100+20*log10(.000185/2.83)=16dB SPL @1m.

But with that components (assuming tweeter matches the amp), you could get maximum SPL about 120dB, right? Scale it down and you probably will get less noise too. And maybe lower price

 

[Roland68]

I mean it seems there are a lot of low-noise amplifiers out there-or am I conflating SINAD with raw output noise? (Well, I know I am, they are not the same thing, but am I crazy many amps are super quiet?). Yet I read SO many comments about hiss from monitors, not always cheap ones. Cost-cutting? Something about gain levels?

What the hell, this is 2026, I do NOT get it. And I do NOT get how any professional would find any level of hiss acceptable at all.

???

That's why I use passive monitors/speakers in my near-field setup.
I'm very sensitive to background noise, and I haven't found an active monitor that was completely silent up to €1000 each.
My two near-field setups with Elac DBR62 and Carina BS243.4 are absolutely silent with a PA5 II and Sabaj A30; I can't hear a thing, even at night.

I feel there's something to do with the way active monitor amps seem to be implemented. It's like running the amp wide open; PC noise comes through readily, whereas on a "normal" amp with volume control, that noise gets turned down with turning down the volume control.
Of course there is the real self noise which cannot be turned down. Things built for robust, more power, maybe cheaper, have more noise along with efficient drivers that play that noise louder at idle

That's unrelated. In my setups, even with the volume turned all the way up, there's absolutely nothing to hear. It's solely down to the quality of the power amplifiers.

 

[RexrothPigeon]

how close are you sitting? I never hear hiss from my monitors

 

[pablolie]

I experience absolutely zero hiss in any of my setups. Especially my main one. I am very noise sensitive so that is a disqualifier to me.

Never forget active monitors have an Amp in there, so they are susceptible to the exact same ground issues separate components may be. If you're using an USB or RCA interface, that may be the issue?

 

[Ralph_Cramden]

Wait a decade or two. You won’t hear any hiss.

 

[Brian Hall]

I mean it seems there are a lot of low-noise amplifiers out there-or am I conflating SINAD with raw output noise? (Well, I know I am, they are not the same thing, but am I crazy many amps are super quiet?). Yet I read SO many comments about hiss from monitors, not always cheap ones. Cost-cutting? Something about gain levels?

What the hell, this is 2026, I do NOT get it. And I do NOT get how any professional would find any level of hiss acceptable at all.

???

Hissing is the only way they have to express displeasure with your music choices.

 

[Ellebob]

Passive speakers hiss as well just usually a lot lower in volume where it might not be noticed. The reason is the crossover in a passive circuit absorbs some of the energy so it reduces the his volume. In an active speaker the amplifier is connected directly to the driver making it very sensitive to noise, so much easier to hear especially in the near field. Newer active designs are much better in general. Here is a thread which discusses it. I would definitely look at Ilka Rissanen's responses from Genelec. He is definitely an expert in this field.

Hissing from Genelec G Two at short range — should I be worried?

Hi - I’ve just bought one Genelec G Two active monitor (one unit), but it has a slight hiss (white noise) even with all input cables disconnected. The noise appears to come from the amplifier (no transformer/coils whining) and is mainly coming from the HF driver - it’s barely audible from the...

www.audiosciencereview.com

 

[dfuller]

I mean it seems there are a lot of low-noise amplifiers out there-or am I conflating SINAD with raw output noise? (Well, I know I am, they are not the same thing, but am I crazy many amps are super quiet?). Yet I read SO many comments about hiss from monitors, not always cheap ones. Cost-cutting? Something about gain levels?

What the hell, this is 2026, I do NOT get it. And I do NOT get how any professional would find any level of hiss acceptable at all.

???

Well, there are a few things going on.

If it's an analog active, any op-amps or other active components used for the filters and any EQ will add noise. This is then amplified by the power amp stage.

If it's DSP, any noise introduced by conversion is amplified too.

In either case, there is nothing dumping signal between amp and driver - so if there's noise, it's all going to the driver. It's always more apparent with the tweeter and sometimes mid than it is with a woofer.

The power amp itself of course has its own self-noise, some are better than others in this department - usually that means higher quality class AB, or Pascal and Hypex Class D modules, or sometimes discrete class D. Almost everything else - ICEPower, class D IC amps, and lesser quality Class AB - can be fairly noisy. That said the Hypex Fusion plate amps can be noisier than expected, I know of at least one company doing a Hypex-approved mod to lower the self-noise.

Nothing in a passive crossover adds any noise (well not at any meaningful level, anyway, technically resistors have some intrinsic noise but it's irrelevant at speaker levels).

 

[pablolie]

...
If it's an analog active, any op-amps or other active components used for the filters and any EQ will add noise. This is then amplified by the power amp stage.

If it's DSP, any noise introduced by conversion is amplified too.
...

But that would also mean the measuremens are not SOTA at all, which should be very evident unless people put all their money into how stuff measures at 96dB+ (don't hold your ear to the tweeter). Unfortunate that's a bit common.
Other than that with competent gear it should be some gear mismatch for several possible reasons.

 

[dfuller]

But that would also mean the measuremens are not SOTA at all, which should be very evident unless people put all their money into how stuff measures at 96dB+ (don't hold your ear to the tweeter). Unfortunate that's a bit common.
Other than that with competent gear it should be some gear mismatch for several possible reasons.

Oh dude, unless you're really buying very expensive stuff no plate amp is anywhere near SOTA. The BOM cost increase isn't even remotely worth it.

Doesn't have to be though, just good circuit design with basic good quality op amps and power amp ICs will do it. Neumann doesn't use anything fancy on the KH310, 420, or 120A - the power amps are all TDA7293s, with MC33079s and TL07x series for the filters... And they're some of the quietest on the market.

 

[kemmler3D]

you will lose way more sales to the increased MSRP, than you would gain from the reduced self-noise which is difficult to communicate/market anyway.

Very correct post overall, but this type of product calculus is very hard to do in practice without expensive surveys. Even then the real-world results are somewhat unpredictable. Price sensitivity for a given non-commodity product is hard to nail down in the first place, once you try to measure the impact of features against price you need long "conjoint analysis" surveys with hundreds or thousands of responses. And if it's all prospective, the results are not rock-solid anyway. Before anyone says "AI can help with this"... lol, I wish.

Tying it back to the conversation in the other thread about the Palmer speaker, Adam Hall is surely big enough to invest in this kind of study and they may have made an informed call on self-noise, but I somehow doubt it. More likely they simply had very tough BOM requirements (unless they are losing their shirts on this speaker, it's a certainty) and they had to go with the cheaper amp rather than cut something more important.