Genelec 8351B Review (Studio Monitor)

[Frank Dernie]

Next we have to get a Neumann KH420, anyone in the lower 48 that wants to ship. I’ll offer to cover shipping both ways. To Amir and back.

Agreed.
It may be a reasonably priced solution which has, perhaps, the capability of competing with the Salon 2 at high levels.

 

[Scgorg]

Comparing that to the M2 we see that the M2 has significantly lower IMD below 1 kHz even when played 8 dB louder than 8361.
For above 1 kHz we don't know because the scaling is different and the tweeter might not take much louder levels before the distortion shoots through the roof on the 8361. For a small speaker, that 8361 looks mighty impressive.

Looks about equal on the IMD to me. Red line at 80dB for the JBL and 90dB for the genelec, but both have most of the IMD about -40dB relative to that (the JBL does look to perform a little better, but not by much). Of course the JBL is playing significantly louder. At least that is the case if the solid blue line is total distortion (IMD+THD) while the "hash" at the bottom is the IMD (that's how I interpret it, correct me if I am wrong). So this seems to tell us that the genelec, at the tested levels, has lower IMD and HD in the upper mids and treble, and comparable IMD in the lower mids/bass, but worse HD.

The genelec would probably just about shit itself at the levels the M2 is playing though, so they're not directly comparable, as you say.

 

[Gorgonzola]

Gosh, the Genelec 8351B is amazing -- arguably for US$10000 a pair it ought to be.

I don't need the high output of the Salon 2's. I really never listen at an average level above 70 dB though as a Classical music listener I need to allow 20 dB for dynamic head room; It seems to me that is no challenge for the 8351B's in my small-medium sized room.

So my only problem is to find something very like the 8351B's in performance but costing no more than US$2000. Any suggestions, folks?

 

[Absolute]

Looks about equal on the IMD to me. Red line at 80dB for the JBL and 90dB for the genelec, but both have most of the IMD about -40dB relative to that (the JBL does look to perform a little better, but not by much). Of course the JBL is playing significantly louder. At least that is the case if the solid blue line is total distortion (IMD+THD) while the "hash" at the bottom is the IMD (that's how I interpret it, correct me if I am wrong). So this seems to tell us that the genelec, at the tested levels, has lower IMD and HD in the upper mids and treble, and comparable IMD in the lower mids/bass, but worse HD.

The genelec would probably just about shit itself at the levels the M2 is playing though, so they're not directly comparable, as you say.

Fair point. I need to double check how to interpret those lines. For easiest readability I would suggest a normalized graph to zero on the top and just write the spl it's normalized to.

 

[Eurasian]

Gosh, the Genelec 8351B is amazing -- arguably for US$10000 a pair it ought to be.

I don't need the high output of the Salon 2's. I really never listen at an average level above 70 dB though as a Classical music listener I need to allow 20 dB for dynamic head room; It seems to me that is no challenge for the 8351B's in my small-medium sized room.

So my only problem is to find something very like the 8351B's in performance but costing no more than US$2000. Any suggestions, folks?

With patience you might find a pair of gently used KH80DSP + KH750 within your budget. I did and couldn't be happier!

 

[Absolute]

Preference Rating
SCORE: 7.1
SCORE w/ sub: 8.4

Frequency response: +/-2.7dB 38Hz-20kHz (spec: +/-1.5dB)

View attachment 129989View attachment 129991​

Quite the difference between horisontal and vertical quality. Diffraction from the bass slots perhaps?

 

[BeerBear]

But... does it hiss?

 

[MZKM]

Quite the difference between horisontal and vertical quality. Diffraction from the bass slots perhaps?

Look at the legend. Vertical goes to +/-40°.

 

[Bernard 54]

This is a review and detailed measurements of the Genelec 8351B powered monitors (speakers). It was purchased used by a member and kindly drop shipped to me for testing. They cost US $4,995 each.

The 8351 is a thee-way speakers with the bass drivers hidden beyond the front baffle:

View attachment 129922

Naturally the back panel allows for fair bit of configuration changes:
View attachment 129923

I reset the speaker to factory settings and left all the dip switches off as you see. I used analog XLR input for all measurements and listening tests.

Measurements that you are about to see were performed using the Klippel Near-field Scanner (NFS). This is a robotic measurement system that analyzes the speaker all around and is able (using advanced mathematics and dual scan) to subtract room reflections (so where I measure it doesn't matter). It also measures the speaker at close distance ("near-field") which sharply reduces the impact of room noise. Both of these factors enable testing in ordinary rooms yet results that can be more accurate than an anechoic chamber. In a nutshell, the measurements show the actual sound coming out of the speaker independent of the room.

I performed over 1000 measurement which resulted in error rate of around 1%.

Testing temperature was around 65 degrees F.

Reference axis for measurements was the center of the tweeter (by eye).

Measurements are compliant with latest speaker research into what can predict the speaker preference and is standardized in CEA/CTA-2034 ANSI specifications. Likewise listening tests are performed per research that shows mono listening is much more revealing of differences between speakers than stereo or multichannel.

Genelec 8351B Measurements
As usual we start with our spin frequency response measurements:
View attachment 129926

I expected flat on-axis response and we essentially get that. There is a tiny bit of deviation in lower frequencies. I checked with Genelec and they looked up the measurements and they are ± 0.5 dB in that region. They show it a bit flatter than I do but I don't think either one of us know whose measurements are more correct. Regardless, the deviation is tiny and your room would overwhelm it in practice.

Directivity plots show off-axis that is similar to on-axis as it should be with coaxial drivers. This is in turn reflected in early-window response and predicted one:

View attachment 129927

View attachment 129928

I don't have near-field driver responses for you since it was silly to try to measure them on a coaxial driver.

Directivity plots of almost textbook perfect:

View attachment 129929

View attachment 129930

View attachment 129931

Edit: forgot to post the distortion graphs before:
View attachment 129970

View attachment 129971


Finally waterfall shows a few resonances:
View attachment 129932

Genelec 8351B Listening Tests
Given the size of this speaker and interest in membership to use them in high-fi and home theater applications, I decided to listen to them using my main system in far field listening. From the first few seconds I knew the sound was right and in need of no adjustment other dialing out the one room mode I have around 105 Hz. Track after track has excellent sound with image coming out of a circular halo around the driver. This is what you get when the speaker is well designed and relies on decades of research on what good sound is. All of my reference tracks that were curated on another system like it translated and delighted just as well.

Dynamics and Competition with Revel Salon 2
There has been a lot of talk about how these two speakers compare in the forum. I find the conversion odd as we are comparing a bookshelf speaker to a full blown tower. Still, I decided to compare the two since I own the Salon 2.

The Salon 2 quickly showed its difference in taller image that was not so focused and centered as the Genelec. This of course could be an optical illusion of the Genelec pulling your eye toward its tweeter. Still, I stand by this observation. The other thing that stood out was that the highs were more prominent in Salon 2 bringing more realism to high frequency notes. The Genelec sounded subdued in this front. Perhaps there is some peaking in my Salon 2 (have not measured it yet).

Where one could not doubt a difference was the power capability and bass extension. On sub-bass heavy tracks the Genelec held its own at lower volume. As you turned up the level the bass driver started to make this annoying "furrrrring" sound on heavy bass notes. You could easily hear it if you stood on top of the speaker and listened through the slot on top. Turn up the volume a bit more and the red clipping indicator would come on.

The Salon 2 was in entirely different class. Powered with 1000 watts of amplification, it provided a level of belly shaking that the 8351B could not even dream about reproducing. And it would keep getting louder and louder with zero distortion and strain. It simply was not a fair fight even though the 8351B tries hard.

Overall, the Salon 2 provides that large, dynamic sound that a statement speaker needs to provide to fill a large space. The 8351 is for more intimate and more focused listening.

Conclusions
Both objectively and subjectively the Genelec 8351B delivers. Near perfection as far as tonality and dispersion is provided. Its power delivery is the best of any Genelec speaker I have tested so far and is almost beyond what you may need. In my case though, I am used to much larger and powerful systems and there, the 8351B was limiting especially with its bass slot noise. So I would not position it above its class.

Overall, it is my pleasure to put the Genelec 8351B on my recommended list.

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As always, questions, comments, recommendations, etc. are welcome.

Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150

Thank you AMIR for this test of my future speaker (combined with W371A). I think you have already stated this in other posts, but could you precise your listening distance?
Many thanks

 

[MediumRare]

No doubt these are awesome, but what does Floyd Toole say about a point source versus a tower or array? How to incorporate the ability to double SPL instantaneously (starting at "loud") for dynamics. Again, our scoring system falls short in predicting preference.

 

[Absolute]

Look at the legend. Vertical goes to +/-40°.

Yeah, I know. Was comparing both to 40. Normalized we see the peaking on the vertical scale. I would assume diffraction. Would be interesting to me to hear from the owners if they can detect differences between horizontal and vertical placement because I would assume this kind of high Q peaks would be audible.

Not really for the reflections, but in the sense that horizontal placement on top of the w371 could possibly be a choice of picking the lesser evil of compromised dispersion pattern vs compromised horizontal frequency response in combination with the w371.

 

[MediumRare]

No I only have one. Genelec has possibly suggested they may send me a pair.

Why would that matter?

 

[Dialectic]

Awaiting the obligatory complaints about the amplification modules in these speakers.

 

[mkawa]

With that preference rating there is nothing to complain about

 

[Robbo99999]

Gosh, the Genelec 8351B is amazing -- arguably for US$10000 a pair it ought to be.

I don't need the high output of the Salon 2's. I really never listen at an average level above 70 dB though as a Classical music listener I need to allow 20 dB for dynamic head room; It seems to me that is no challenge for the 8351B's in my small-medium sized room.

So my only problem is to find something very like the 8351B's in performance but costing no more than US$2000. Any suggestions, folks?

Stop it with the $$$$$$! (Don't support the unreachable!)

 

[BrokenEnglishGuy]

Gosh, the Genelec 8351B is amazing -- arguably for US$10000 a pair it ought to be.

I don't need the high output of the Salon 2's. I really never listen at an average level above 70 dB though as a Classical music listener I need to allow 20 dB for dynamic head room; It seems to me that is no challenge for the 8351B's in my small-medium sized room.

So my only problem is to find something very like the 8351B's in performance but costing no more than US$2000. Any suggestions, folks?

Kef r3 measure really well
I want to see the genelec 8351 at 104dB as the kef r3 was tested

 

[MZKM]

what does Floyd Toole say about a point source versus a tower or array?

I believe Erin asked him that in his video, and I believe he responded with he doesn’t know.

 

[Sprint]

Gosh, the Genelec 8351B is amazing -- arguably for US$10000 a pair it ought to be.

I don't need the high output of the Salon 2's. I really never listen at an average level above 70 dB though as a Classical music listener I need to allow 20 dB for dynamic head room; It seems to me that is no challenge for the 8351B's in my small-medium sized room.

So my only problem is to find something very like the 8351B's in performance but costing no more than US$2000. Any suggestions, folks?

I went with 8340 as LCR and 8330 as surrounds for my living room set up. I use a pair of SVS 12" subs. For 2K, I would have looked into KS Digital C88 but am not sure if it is available in the US. If you can increase your budget, the end game will be a pair of 8350 (non coaxial version of 8351) or a pair of KH310 and a sub of your choice. On an AB comparison in one of the nearby stores, I loved Genelec 8350 even though they were 2 way in comparison KH310 but the differences were not much. I could have happily lived with both of them. Then there is HEDD or ADAMs.

 

[JustJones]

Maybe I missed someone pointing it out by I didn't pay $4995 a piece USD for the 8351b, they listed for $3995 and I ended up paying $3600 a piece. I also noticed some distortion in the bass but adding 2 Genelec subwoofers really made a difference as GLM let's you pair them up left/ right with the 8351b's.

 

[Sprint]

Maybe I missed someone pointing it out by I didn't pay $4995 a piece USD for the 8351b, they listed for $3995 and I ended up paying $3600 a piece. I also noticed some distortion in the bass but adding 2 Genelec subwoofers really made a difference as GLM let's you pair them up left/ right with the 8351b's.

which Genelec subs did you pair with?