Genelec 8351B Review (Studio Monitor)

[Pete James]

Here are compression measurements of a single 8351B with 2 Arendal 1723 2S subwoofers at roughly 2.5 meters. As you can see, you need a lot of sub just to keep up with 1 8351B. With 2 or more playing, my subs are still the bottleneck of my system, not the speaker. At least if you care about performance below 40hz.

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Thanks that’s really helpful. It seems like there’s really no need to step up to the 8361 unless you want to go without a sub and even then maybe the 8361 low end isn’t much good compared to dedicated subs. Do these kind of tests account for dynamic range? Maybe I could get away with the 8341 but the 51 seems a safe bet.

What’s your impression of the character and performance or arendal subs?

I’m looking into subwoofers quite a lot at the moment and it’s great they have XLR. My 153 ft2 / 1260 ft3 DJ / Studio room. It’s for music only but I almost exclusively play bass heavy percussive house and techno so I want that feeling for punch and slam that I get with a high end club sound system like funktion one or void but at home. However I still need it to be precise and accurate to be able to judge music production and mixing decisions. Is this even possible to have these characteristics from the same sub - if it is sounds like I either need 2 different subs or someone suggested JL audio would do both but they are so expensive! I heard SVS are great for punch and slam but overall not very good for music. I also heard REL are great for music offering precision and accuracy but lacking in punch, slam and excitement plus they don’t have XLR. I could also import an RSL speedwoofer 12

 

[Mort]

Absolutely go with genelec subwoofers. The glm room correction is far superior in phase adjustment than any other DSP out there imo.

 

[Mort]

I have both 8351b with 7370a and 8361a with a 7380a. I can't tell the difference except Max volume, about 3db with bass heavy music.

 

[Pekka Perämoottori]

This kind of small speakers don't work properly unless they are VERY CLOSE to the listener, when there is a tabletop (representing the "floor") 20-30 cm underneath of them. Very close means 1- 1,5 meters away at the most. Otherwise, the floor reflection penalty shot (deep cancellation) is maximal if placed on a typical speaker stand, and the listener is a couple of meters or further away, in normal seated listening height.

In a typical non-tabletop -living room installation, you should have a NON-COAXIAL three-way with a cabinet height of at least, say, 80 cm, a bass/midrange crossover frequency of <500 Hz, a bass driver that can be installed at a height of 20-30 cm from the floor. And only the drivers that reproduce frequencies >500 Hz, at the height of the ear sitting in the listening position.
In Genelec's range, this means the minimum qualified model size for such a installation would be 1238A, then.

This way you can avoid that, otherwise really difficult to avoid, first multiple of the floor reflection. Which pops a VERY bad null-cancellation in the room response, around the upper bass/lower midrange.
This gaping crater can be found in almost every bookshelf speaker room response that can be found on the internet. But, as said, it could be avoided: by choosing speakers that are better suited to the intended purpose.


Check it out for yourself with a floor reflection calculator if you don't believe it:

Floor/Ceiling Reflection Calculator

Fortunately, unlike pretty much all other small speakers in the market, floor reflection -compatibility of the 83xx -coaxials can be enhanced to be suitable also for non-tabletop -use, with the W371 -woofer system. A rather unheard of option, that is.



Floor reflection is particularly bad and important to keep an eye on, because it´s so hard/impractical to deal with means of acoustical treatment. The basic audiophile treatment, a carpet (even a thickest one) on the floor, between the speakers and the listening position, still doesn't help at all. The room curve remains as rough with a crater as without a carpet.
So real sensible way to tame it would be to control the vertical reflections generated by the speaker itself, with its structural properties.

 

[tmtomh]

This kind of small speakers don't work properly unless they are VERY CLOSE to the listener, when there is a tabletop (representing the "floor") 20-30 cm underneath of them. Very close means 1- 1,5 meters away at the most. Otherwise, the floor reflection penalty shot (deep cancellation) is maximal if placed on a typical speaker stand, and the listener is a couple of meters or further away, in normal seated listening height.

In a typical non-tabletop -living room installation, you should have a NON-COAXIAL three-way

This is nonsense.

 

[Pekka Perämoottori]

This is nonsense.

Is that so?
Grab a floor reflection calculator, use your brain and THINK about those mentioned things.

The acoustic fact is that the floor is banging with ugly cancellation for the upper bass/lower midrange area, for all speakers of the size of 83xx -series Genelecs, mounted on the top of a typical 50 - 100 cm stand, with the typical other dimensions of such a listening setup.

It is also a fact that you can hardly treat the floor acoustically, because you have to be able to walk on it. The walls and ceiling can be treated, but the floor has to be left alone. So we have a pretty obvious practical acoustic problem here, if we leave it at that.

A large traditional three-way like 1238A, with a bass/midrange -crossover frequency of 420 Hz, can avoid this at that 20-30 cm installation height.
The first reflection hitting the height of the bass driver is no longer in its reproduction range (the reproduction has already been filtered to the mid driver), and the reflection hitting the height of the mid driver is no longer in its reproduction range (the reproduction has already been filtered to the bass driver): in theory, the first (the worst) floor reflection dip is thus not formed at all.

 

[NTK]

Is that so?
Grab a floor reflection calculator, use your brain and THINK about those mentioned things.

The acoustic fact is that the floor is banging with ugly cancellation for the upper bass/lower midrange area, for all speakers of the size of 83xx -series Genelecs, mounted on the top of a typical 50 - 100 cm stand, with the typical other dimensions of such a listening setup.

It is also a fact that you can hardly treat the floor acoustically, because you have to be able to walk on it. The walls and ceiling can be treated, but the floor has to be left alone. So we have a pretty obvious practical acoustic problem here, if we leave it at that.

A large traditional three-way like 1238A, with a bass/midrange -crossover frequency of 420 Hz, can avoid this at that 20-30 cm installation height.
The first reflection hitting the height of the bass driver is no longer in its reproduction range (the reproduction has already been filtered to the mid driver), and the reflection hitting the height of the mid driver is no longer in its reproduction range (the reproduction has already been filtered to the bass driver): in theory, the first (the worst) floor reflection dip is thus not formed at all.

Read this post.

Post in thread 'Most beautiful speakers in the world ?'

Apr 4, 2025

We have to remember that the floor bounce is often accompied by other cancellations in the same region. This means the level in this region can often end up being something 5 dB too low compared to a Bruele & Kjaer response and that over a fairly wide area. I have listened to both in short AB comparisons and over time. Cabinets and speaker drivers were identical besides the different positions.

To me there's no doubt that having an even response here is very important. Especially when listening to various music material. It sounds more correct in regards to the tonality, less bright...

• Floyd Toole

• 

 

[Pekka Perämoottori]

Read this post.

Post in thread 'Most beautiful speakers in the world ?'

Apr 4, 2025

We have to remember that the floor bounce is often accompied by other cancellations in the same region. This means the level in this region can often end up being something 5 dB too low compared to a Bruele & Kjaer response and that over a fairly wide area. I have listened to both in short AB comparisons and over time. Cabinets and speaker drivers were identical besides the different positions.

To me there's no doubt that having an even response here is very important. Especially when listening to various music material. It sounds more correct in regards to the tonality, less bright...

• Floyd Toole

• 

Yeah yeah. Nothing is a problem until you realize the problem. And it becomes a problem. Knowledge adds to the pain.

It seems to be the same nonsense that heavily boosted Harman curve basses and some 2ch music SHOULD HAVE a certain amount of reverberation when listening to speakers... hehe hehe.

Real modern day zero colorature listeners, who have trained themselves with pure headphone playback for years, are very used to a such minimally colored sound, like breathing. Will certainly notice any deviation from that in use! The upper bass / lower midrange are missing their balls. No real listener wants that kind of thing in their playback voluntarily, if they can avoid it. And they can: by choosing the right kind of speaker for the intended purpose.

And yes, meter-hi-fi -enthusiast will just squirm like a hungover squirrel if the room response has such an (avoidable) disability and he KNOWS ABOUT IT: like a second nose growing on the forehead drawn by artificial intelligence. If you ask a suitable research professor / Santa Claus, it probably shouldn't bother that much (as long as there's at least a nose in the picture, that's the most important thing). But it REALLY bothers attentive viewers. IT DOES.

So. If you don't want that promised cancellation canyon in your speakers' room response, but want as clean a reproduction as possible, these small speakers that require a high stand are not suitable outside the near field. Even if they are otherwise very hi-tech and *)audio-Jesus himself had one of those.







*) The story goes that audio-Jesse only found out about the small speaker's floor dip -related hard truth after this: the reference speaker was then replaced quite soon.

 

[Behrelec 37]

Does countryman Pekka himself have these 1238a tool monitoring monitors, if I may ask?

 

[Sancus]

Do these kind of tests account for dynamic range? Maybe I could get away with the 8341 but the 51 seems a safe bet.

This is a sweep and it was a fairly slow one so there will be a little more headroom than that for very short transients. But in general, you need to account for dynamic range yourself. 100dB is a LOT though, if you listen at 80dB average(fairly loud to me) that gives you 20dB of dynamic range, which is plenty for most music. In my testing the (single!) speaker does 105dB without any trouble, which is enough for almost anything.

I have some multichannel(this often has higher dynamic range than similar stereo recordings) classical recordings that measure at ~30dB of dynamic range, but this is spread over multiple speakers. I also tend to listen to high dynamic range material at even lower average levels, around 75-77dB, because otherwise the peaks become painfully loud.

What’s your impression of the character and performance or arendal subs?

They work great, and I like that they don't vibrate at all because they're dual opposed. This is really a quality of life feature, it doesn't improve sound quality but it does mean you can use one as an end table which is what I'm doing For subs, there isn't that much difference in the quality of sound, you mainly just want something with good SPL capability and low group delay. Most sealed subs have low group delay, so that resolves that. Ported subs have more potential issues, but many modern designs are just fine as well. I picked Arendal because they looked nice, there were measurements showing low group delay, and the price was acceptable.

My setup is tuned with multi-sub optimizer so it works just as well as a glm setup would, if not better, IMO. Of course, it is quite a bit more manual work. But I don't like the aesthetics of Genelec subs and they are definitely expensive for the performance level. You are paying for integration convenience, which GLM is definitely very very good at.

 

[cputoaster]

This is a sweep and it was a fairly slow one so there will be a little more headroom than that for very short transients. But in general, you need to account for dynamic range yourself. 100dB is a LOT though, if you listen at 80dB average(fairly loud to me) that gives you 20dB of dynamic range, which is plenty for most music. In my testing the (single!) speaker does 105dB without any trouble, which is enough for almost anything.

I have some multichannel(this often has higher dynamic range than similar stereo recordings) classical recordings that measure at ~30dB of dynamic range, but this is spread over multiple speakers. I also tend to listen to high dynamic range material at even lower average levels, around 75-77dB, because otherwise the peaks become painfully loud.

They work great, and I like that they don't vibrate at all because they're dual opposed. This is really a quality of life feature, it doesn't improve sound quality but it does mean you can use one as an end table which is what I'm doing For subs, there isn't that much difference in the quality of sound, you mainly just want something with good SPL capability and low group delay. Most sealed subs have low group delay, so that resolves that. Ported subs have more potential issues, but many modern designs are just fine as well. I picked Arendal because they looked nice, there were measurements showing low group delay, and the price was acceptable.

My setup is tuned with multi-sub optimizer so it works just as well as a glm setup would, if not better, IMO. Of course, it is quite a bit more manual work. But I don't like the aesthetics of Genelec subs and they are definitely expensive for the performance level. You are paying for integration convenience, which GLM is definitely very very good at.

FWIW, I have the 8351b with 2x1723 1S (and some smaller Genelec for surround), all optimized together through a DIRAC box. Works great and am also using the subs as tables when not watching very sub-heavy movies.

 

[Mort]

There are a pair of 8351b in grey on eBay for $5500 a pair. Lowest used price I've seen.

 

[Arnas]

There are a pair of 8351b in grey on eBay for $5500 a pair. Lowest used price I've seen.

Great Christmas present for someone lucky!

 

[outfaced]

interesting comparison