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Kef LS50 meta (+ sub + Benchmark AHB2) or Genelec 8331a (+ sub)

Tangband

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Loads of people would say there was 0 hiss with the 8030C too, but I can hear it anyway. Don't tend to trust anecdotes with those now, as they're obviously very personal. It's why I just want to know if the hiss decreases when turning it down in GLM, nothing more.
Because you dont listen to all of us that says the 83xx series is quiet, you have to listen for yourself . :)
 

lc155

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Because you dont listen to all of us that says the 83xx series is quiet, you have to listen for yourself . :)

Which isn't really possible as there's no way to try it out locally without having to drop the money on a set, so :)
 
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rillettes

rillettes

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I recently received a pair of 8351b (for another installation in my house), first time I listened to Genelecs.

1. They're awesome in so many ways... The most striking is how well low bass is integrated with the rest of the spectrum. I've listened to a lot of fancy gear in my life, including stuff way beyond my budgets in fancy hifi shops, and never had this feeling of reality when listening to contrabasses or bass guitar + drums in a heavy metal track. They can also reproduce effortlessly a complex signal, e.g. full orchestra, or angry death metal where the drummer and guitarists run a contest of who can play all their drums / strings at the same time and make the most noise ;) It feels like you just hear everything, with perfect tonality, and with lots of power in reserve.

2a. There is hissing, even with all sources disconnected. I'd say the threshold of audibility for me is around 40cm from the loudspeaker. I plan to try and measure it later when I have more free time. They're currently setup so that my listening position is ~150 cm from the speakers, way beyond the threshold of audibility for this hiss. So for now I can't tell if this would be a bother in a desktop setup (assuming that the 8331s have the same hissing level). It'll also be difficult to test the 8351Bs at my desktop, because they're too big.

2b. My 2c on this topic, I don't understand why hissing would be intrinsic to active speakers. If it's intrinsic to power amplifiers running at full capacity, then all power amplifiers would have the same issue (even with passive speakers connected to them). If it's intrinsic to active crossovers, then it's an active crossover issue. Which I would also have if I setup a sub + active crossover + AHB2 + Kef LS50 (which was suggested in this thread).
This is quite an interesting topic, but would deserve a dedicated thread :)

Back on-topic, given all the feedback I received, I didn't pull the trigger on the LS50s, instead I sold the AHB2. With regrets, but rationally I don't have any use for it anymore. I plan to go for the 8331s, just not immediately due to the higher budget. And I'm also giving priority atm to saving money for a pair of W371As to go with the 8351Bs, but that's another topic :)
 

Digby

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My 2c on this topic, I don't understand why hissing would be intrinsic to active speakers. If it's intrinsic to power amplifiers running at full capacity, then all power amplifiers would have the same issue (even with passive speakers connected to them). If it's intrinsic to active crossovers, then it's an active crossover issue. Which I would also have if I setup a sub + active crossover + AHB2 + Kef LS50 (which was suggested in this thread).
Someone explained this for me in another thread, I can't find it now, but perhaps they will come along or someone will remember the thread and link it.

Gens hiss, perhaps all active speakers hiss (if you sit close enough). If you are young/sensitive/close and the noisefloor of the room is low enough, it may annoy or may be tolerable. This also depends on the character of the hiss, some active speakers hiss (Gens) and some HISS.
 
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lc155

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2a. There is hissing, even with all sources disconnected. I'd say the threshold of audibility for me is around 40cm from the loudspeaker. I plan to try and measure it later when I have more free time. They're currently setup so that my listening position is ~150 cm from the speakers, way beyond the threshold of audibility for this hiss. So for now I can't tell if this would be a bother in a desktop setup (assuming that the 8331s have the same hissing level). It'll also be difficult to test the 8351Bs at my desktop, because they're too big.

2b. My 2c on this topic, I don't understand why hissing would be intrinsic to active speakers. If it's intrinsic to power amplifiers running at full capacity, then all power amplifiers would have the same issue (even with passive speakers connected to them). If it's intrinsic to active crossovers, then it's an active crossover issue. Which I would also have if I setup a sub + active crossover + AHB2 + Kef LS50 (which was suggested in this thread).
This is quite an interesting topic, but would deserve a dedicated thread :)

Well, no, because the amps you use with passive speakers are never used at full capacity. That's the difference. You will likely hear a hiss on many passive speaker amps if you turn them way up, but since you never need to go anywhere near that for nearfield as they're usually used at a fraction of their volume capacity, it is almost never a problem. On active speakers you typically control the volume via the DAC which then the amp at full blast sends to the speakers, no way of getting around that.

Now that you've identified the hissing, if you intend to get a GLM setup, I would be most interested if you could try turning down the amp gain via GLM to see what happens with the hiss. There's no point asking those like Tangband because they refuse to acknowledge a problem exists.
 
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rillettes

rillettes

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Well, no, because the amps you use with passive speakers are never used at full capacity.
There is where we disagree / I don't understand you. A power amp always operates at full gain (modulo the sensitivity switch for some of them).
 

lc155

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There is where we disagree / I don't understand you. A power amp always operates at full gain (modulo the sensitivity switch for some of them).

Have you never noticed an increase in hiss when turning the volume all the way up on an amp due to noise from amplifier gain? That is what I am talking about. You can gain-stage passive speaker amps fairly easily.

To be quite honest, I'd be baffled if you claim you've never experienced this.
 
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rillettes

rillettes

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Have you never noticed an increase in hiss when turning the volume all the way up on an amp due to noise from amplifier gain? That is what I am talking about. You can gain-stage passive speaker amps fairly easily.

To be quite honest, I'd be baffled if you claim you've never experienced this.
I have an integrated amp, which indeed produces hiss when cranked to full power. But that noise is generated from its preamp section. In AV mode, which is just power amp mode, without any source connected, there's no hiss.
Now when I connect my minidsp to this AV input, then I get a hiss. This one is generated by the minidsp. It doesn't happen for instance with a Yamaha WXC-50.

The big question what's generating the noise. I believe the 8351s have very silent amplifiers, so my guess would be the active crossovers.

(Edit: for those wondering, the minidsp is a 2x4)
 

Tangband

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I have an integrated amp, which indeed produces hiss when cranked to full power. But that noise is generated from its preamp section. In AV mode, which is just power amp mode, without any source connected, there's no hiss.
Now when I connect my minidsp to this AV input, then I get a hiss. This one is generated by the minidsp. It doesn't happen for instance with a Yamaha WXC-50.

The big question what's generating the noise. I believe the 8351s have very silent amplifiers, so my guess would be the active crossovers.

(Edit: for those wondering, the minidsp is a 2x4)
You could try lower the gain in the Genelec 8351 to -20 . The default , if its the same as 8340, is probably 0 dB , wich is very high and only need very little input to play loud.

For home use is -20 dB ( set with the dip switch at the back ) probably better .

There are three ways to set gain on a SAM monitor - dip switches at the back , volume settings in GLM and a rotary knob on the backside .

Without proper gain settings, an active loudspeaker is not used optimaly regarding SINAD , noise and distortion .
 
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rillettes

rillettes

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The noise level is exactly the same with or without the -20dB switched raised.
Which I find... unexpected.

Test protocol:
- power up the speaker with all switches lowered (which implies no GLM correction)
- play music
- raise the -20dB switch: the volume is lowered significantly
- stop the music, listen for the hiss (ear at ~10 cm from the tweeter)
- lower the -20dB switch, while keeping the ear at the same position: the hiss keeps the same volume

I also tried to measure SPL variations with REW + umik-1, but this was all below measurements noise.
 

lc155

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The noise level is exactly the same with or without the -20dB switched raised.
Which I find... unexpected.

Test protocol:
- power up the speaker with all switches lowered (which implies no GLM correction)
- play music
- raise the -20dB switch: the volume is lowered significantly
- stop the music, listen for the hiss (ear at ~10 cm from the tweeter)
- lower the -20dB switch, while keeping the ear at the same position: the hiss keeps the same volume

I also tried to measure SPL variations with REW + umik-1, but this was all below measurements noise.

Well, that isn't looking hopeful for turning it down with GLM either.

When I had my 8030c, the -6dB switch did nothing for me either in terms of hissing.
 

Tangband

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The noise level is exactly the same with or without the -20dB switched raised.
Which I find... unexpected.

Test protocol:
- power up the speaker with all switches lowered (which implies no GLM correction)
- play music
- raise the -20dB switch: the volume is lowered significantly
- stop the music, listen for the hiss (ear at ~10 cm from the tweeter)
- lower the -20dB switch, while keeping the ear at the same position: the hiss keeps the same volume

I also tried to measure SPL variations with REW + umik-1, but this was all below measurements noise.
What happens if you lower the gain with the rotary knop on the back of the Genelecs instead ?
 

BrokenEnglishGuy

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2a. There is hissing, even with all sources disconnected. I'd say the threshold of audibility for me is around 40cm from the loudspeaker.
So many fanboys told me that genelecs doesn't hiss.. lol





I always wanted measures from actives speakers, is just not equal to compare with all of that rigurosity the passive components, while actives components measures bad but the speaker is fine



Hiss just contaminates the room and the music, because is like listening music while there is a lot of people near you talking or screaming, it is not harmless... at 40cm is a lot of noise. Sinad should be what? 80db? headless panter? lol
 
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