I know this is a Synthesis thread but thought I'd ask the following in here as I know many of you have experience with the JBL 3677. E.g. @fallinlight @Smurfin @Arcam_boy @LittleNipper

The specs give a frequency response of up to 12kHz. Which is a fair bit lower compared to the more regular 20kHz I typically see, and the XTZ M6 I currently have are rated up to 30kHz, so 12kHz is far below that. I know our hearing doesn't go that high so above 20kHz is probably not that important, but what about that 12 to 20kHz range? I'm just wondering if that rolloff at 12kHz causes any audiable issues - is anything lost compared to something that goes higher like the M6?

I know @fallinlight you were saying you were told to pay attention to the highs when comparing the 3677s and the M6s and iirc you described them as falling apart. But as the 3677 are highly regarded, how much was that actually a real issue in normal listening? And was it just in music or movies too? Was this reduced frequency response perhaps the reason you couldn't quite commit to the 3677 over your M6?

And to other owners/past owners, did you notice anything lacking due to the 12kHz rolloff? Most people love them so perhaps everything else outweighs any drawback from it?

Reason for asking is the 3677s are on my wish list for L&R, but as they are hard to find I'm also considering a slightly different set which also has the same 12kHz frequency response...

Thanks
The 3677s don't roll off that much, and it's addressable by room correction. I never found it to be an audible issue really.

Here's a rough measurement I took of one of the 3677s I owned, showing pre and post room correction.
 
I know this is a Synthesis thread but thought I'd ask the following in here as I know many of you have experience with the JBL 3677. E.g. @fallinlight @Smurfin @Arcam_boy @LittleNipper

The specs give a frequency response of up to 12kHz. Which is a fair bit lower compared to the more regular 20kHz I typically see, and the XTZ M6 I currently have are rated up to 30kHz, so 12kHz is far below that. I know our hearing doesn't go that high so above 20kHz is probably not that important, but what about that 12 to 20kHz range? I'm just wondering if that rolloff at 12kHz causes any audiable issues - is anything lost compared to something that goes higher like the M6?

I know @fallinlight you were saying you were told to pay attention to the highs when comparing the 3677s and the M6s and iirc you described them as falling apart. But as the 3677 are highly regarded, how much was that actually a real issue in normal listening? And was it just in music or movies too? Was this reduced frequency response perhaps the reason you couldn't quite commit to the 3677 over your M6?

And to other owners/past owners, did you notice anything lacking due to the 12kHz rolloff? Most people love them so perhaps everything else outweighs any drawback from it?

Reason for asking is the 3677s are on my wish list for L&R, but as they are hard to find I'm also considering a slightly different set which also has the same 12kHz frequency response...

Thanks
For HC they will destroy those MK950s you thinking of swapping to!

Going to Mk950s would be a backwards move from the M6 imo.

When I owned the 3677s, I didn't notice any loss of high end, I didn't really use them for critical music listening though.
 
depends if you want a flat FR or use a House curve
a lot of house curve examples suggest rolling off at 10KHz so can't see there would be an issue
 
I know @fallinlight you were saying you were told to pay attention to the highs when comparing the 3677s and the M6s and iirc you described them as falling apart. But as the 3677 are highly regarded, how much was that actually a real issue in normal listening? And was it just in music or movies too? Was this reduced frequency response perhaps the reason you couldn't quite commit to the 3677 over your M6?

Hi AFM1,

Hope you are well and it's nice to read from you, buddy. It's always exciting to see the 3677 - or any JBL speakers for that matter brought up in conversation, as the 3677 and SAM are some of my favourite speakers.

Yes, that is correct, Jag had warned me about the high end of the 3677 when I first got them and I never saw his point until late in my ownership of them when I compared them directly to my M6. For me, the M6 are much more detailed and clear in the highs. For me, this was more of an issue with critical listening/ music listening. I first heard this listening to Van Morrison's Moondance and I was shocked by how much better the M6 were for me with music.

But what I felt was weaker high end performance also presented itself for me in films. However, it was less of an issue for me with films however, because the sheer overall strong performance of the 3677 for films was enough for me to prefer it over my M6 for films, notably it's far larger scale, far stronger dynamics, and ability to better convey the nuance and emotion of things like voices and string sections.

So, yes, I would say that your below statement rang true for me for films in the sense that,

Most people love them so perhaps everything else outweighs any drawback from it?

Some standout moments for me where all of the above sonic qualities were on display were, Man of Steel's opening scenes of action as Krypton is dying, where the 3677 conveyed the sense of scale of the epic scenes with aplomb, Jurassic Park when Hammond and cohort land and as Attenborough walks into shot when William's score swells, my room was filled with sound in a way that no speaker since, including my old SAMs were able to do, and Clannad's I will find You towards the closing scenes of Last of the Mohicans, in which Enya's voice was so beautifully emotive and nuanced. Action scenes depicting war in 1917 and Saving Private Ryan were also incredible standout moments of amazing dynamic sound.

So, I think as always, it simply depends on how you listen and what you value from sound reproduction. As the above responses show, it also depends on your application of the sound within your system, for example room EQ and general mileage. If you think that you might hear the loss of high end detail and transparency that I - and some others - have described, then make it a point for consideration. If not, then don't worry about it. And do note that a few others on AVF disagree with me about my observations.

Reason for asking is the 3677s are on my wish list for L&R, but as they are hard to find I'm also considering a slightly different set which also has the same 12kHz frequency response...

Which set of other speakers are you also considering, @AFM1? I hope you can find something that you will be happy with.

Best wishes,

Rajiv
 
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I know this is a Synthesis thread but thought I'd ask the following in here as I know many of you have experience with the JBL 3677. E.g. @fallinlight @Smurfin @Arcam_boy @LittleNipper

The specs give a frequency response of up to 12kHz. Which is a fair bit lower compared to the more regular 20kHz I typically see, and the XTZ M6 I currently have are rated up to 30kHz, so 12kHz is far below that. I know our hearing doesn't go that high so above 20kHz is probably not that important, but what about that 12 to 20kHz range? I'm just wondering if that rolloff at 12kHz causes any audiable issues - is anything lost compared to something that goes higher like the M6?

I know @fallinlight you were saying you were told to pay attention to the highs when comparing the 3677s and the M6s and iirc you described them as falling apart. But as the 3677 are highly regarded, how much was that actually a real issue in normal listening? And was it just in music or movies too? Was this reduced frequency response perhaps the reason you couldn't quite commit to the 3677 over your M6?

And to other owners/past owners, did you notice anything lacking due to the 12kHz rolloff? Most people love them so perhaps everything else outweighs any drawback from it?

Reason for asking is the 3677s are on my wish list for L&R, but as they are hard to find I'm also considering a slightly different set which also has the same 12kHz frequency response...

Thanks

To be honest, I've never looked at the graphs showing the response I just know they sound cracking. I have however added my frequency response for the LCR from the Trinnov. It does show them rolling off over 10k. However, I do have a traget curvey that rolls them off and don't know if that effects the first first graph ?

All I know is they sound amazing ! If your in my area your welcome to listen.
 

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Thanks for the feedback all, very useful. Just trying to understand better.

@fallinlight I've found a set of JBL 3678s, so I'm thinking of pairing two of those as L and R with the JBL 880 as a centre. With the JBL 8320s as surrounds. I think the general view is the 3678s aren't as good as the 3677s, but those are hard to find so thought I'd give the 3678s a try. A bit ugly but will be behind the screen.

Will give these all a try for a bit and if it doesn't work out I can sell and keep my current XTZ set, or go M&K 150. Either way I need to offload the XTZ S5 as side surrounds as they stick out too much. Plan is to use the 8320s and if I don't get on with those as direct firing I'd go for the M&K IW150T.

Will need to move the screen out to accommodate the 3678s, so will need to chisel out a recess either behind each speaker or behind the projector to maintain throw ratio, so a bit of a faff, but hey ho...

Edit - I forgot about the '3677 at home' thread - should probably have posted my first message there but nevermind.

Thanks all
 
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The 3677s are spectacular.
The M6s are good.
There is literally no comparison though.
In a dedicated room, I'd go JBLs even if they were twice the price of the M6s.

Can't comment on the M&K 950s as I've not heard the latest iterations, but if the core signature is the same....I'd take the 3677s in a heartbeat too.
 
Thanks Smurfin. I've pretty much discounted the MP950s. I may consider the MP150s, but at the moment really it's just trying out the JBLs against my current XTZs. I may need M&K for the side surrounds (IW150T) if I end up missing tripoles and don't get on with the JBLs on the sides as direct firing so close to the side seats.

If I could find the 3677s then I'd get them 100%. The 3678s are a bit more of an unknown quantity, hence wanting to know more about that 12kHz response before going for them. Will give them a shot and report back.

Didn't really want to be chasing out a 3" deep projector-sized hole for a recess in my brick wall just to fit the deeper JBLs in, but no pain no gain I guess...!
 
Thanks Smurfin. I've pretty much discounted the MP950s. I may consider the MP150s, but at the moment really it's just trying out the JBLs against my current XTZs. I may need M&K for the side surrounds (IW150T) if I end up missing tripoles and don't get on with the JBLs on the sides as direct firing so close to the side seats.

If I could find the 3677s then I'd get them 100%. The 3678s are a bit more of an unknown quantity, hence wanting to know more about that 12kHz response before going for them. Will give them a shot and report back.

Didn't really want to be chasing out a 3" deep projector-sized hole for a recess in my brick wall just to fit the deeper JBLs in, but no pain no gain I guess...!
The 880 is an awesome centre mate 😉😂
 
Are you guys really comparing JBL and M&K? :confused: I mean, that's not even a contest is it? And while we're at it, throw QSC into the mix, many in the film industry prefer those over the older JBLs. Or just go all in with some M2s. :D
 
The 880 is an awesome centre mate 😉😂
Yeah looking forward to trying it out - can't wait to pick it up this weekend!

Also thinking of getting three of the 3678s rather than just two, so I have the option of a matching full LCR if I want. Am going to be drowning in speakers pretty soon, but probably easier to sell on three if I don't get on with them rather than just two, and if I do prefer the 880 as the center rather than a matching 3678 then I can keep the third as a spare or something.
 
Are you guys really comparing JBL and M&K? :confused: I mean, that's not even a contest is it? And while we're at it, throw QSC into the mix, many in the film industry prefer those over the older JBLs. Or just go all in with some M2s. :D
Not really. I may have conflated things from recent musings.

For my case my current XTZ S5 side surrounds have to go as they will be too close to the side seats so I need something slimmer (the issue is more squeezing between the speaker and the seat rather than an audio issue, though that is obviously still a consideration). I have some JBL 8320s for rear surrounds and am picking up two more for side surrounds - these stick out a similar amount but due to the angled baffle it's not as big of an obstruction as the S5s. But they are direct firing so may be distracting being so close, and I may miss tripoles. Therefore I may get some M&K IW150Ts for side surrounds (mounted ON wall, in a diy box) as they are tripole and shallow. As I might be going M&K for the side surrounds, I considered the MP150s for the front mains, but I have a desire to try the JBLs so am focusing on those first. If I don't get on with them I'll either stick with the XTZs or try swapping those for M&K MP150.

But for now, as the 3677s are so hard to find I'm taking a punt on the 3678s - paired with the 880 as the center, but with a third 3678 as a backup if needed.
 
Not really. I may have conflated things from recent musings.

For my case my current XTZ S5 side surrounds have to go as they will be too close to the side seats so I need something slimmer (the issue is more squeezing between the speaker and the seat rather than an audio issue, though that is obviously still a consideration). I have some JBL 8320s for rear surrounds and am picking up two more for side surrounds - these stick out a similar amount but due to the angled baffle it's not as big of an obstruction as the S5s. But they are direct firing so may be distracting being so close, and I may miss tripoles. Therefore I may get some M&K IW150Ts for side surrounds (mounted ON wall, in a diy box) as they are tripole and shallow. As I might be going M&K for the side surrounds, I considered the MP150s for the front mains, but I have a desire to try the JBLs so am focusing on those first. If I don't get on with them I'll either stick with the XTZs or try swapping those for M&K MP150.

But for now, as the 3677s are so hard to find I'm taking a punt on the 3678s - paired with the 880 as the center, but with a third 3678 as a backup if needed.
Might be worth considering arendal 1723s as surrounds as well.

You’ll hear on Saturday that they don’t sound close to your ear in my room, whereas my previous xtz s5 were terrible for this.

The arendals also blend seamlessly with the JBL’s
 
Thanks, will be good to hear then too. But it's more a physical issue rather than audio. From the outside edge of the seat arm to the wall it's 50cm, and the door is in the back left corner, so you have to physically walk / or rather squeeze between the left side surround and the seat to get to the front row.

The S5s are just too deep to not cause annoyance over time. The 8320s would work due to the angle making it a bit easier to get past, though aren't tripoles, and the M&K are ideal at 95mm deep, though a big chunk of cash more. The Arendals are shallower than the S5s, but from memory I don't think by that much (5cm maybe iirc?) so I think they would still be a bit of an obstruction compare to the IW150T and even the 8320s with the angled baffle.
 
the M&K are ideal at 95mm deep, though a big chunk of cash more.

Oh man that is massive price difference to JBLs and nearly twice to 1723 S still. Reading between the lines on a chat with Arendal they should introduce in-wall 1723 speakers 2023, but are they all just monopoles..

IW150T - 2400£/pair
1723 S Surround 1300£/pair
JBL 8320 - 606£/pair

Any other options? 🥺
 
Not as far as I can tell, if you want a tripole and want it to be shallow. The IW150T is quite a nifty little design in that respect, but yes, pretty pricey.

So think I'll try the 8320s, which would mean JBLs all round, and if needed (i.e. if the direct firing so close is too distracting for the outside seats), move to the iw150t.
 
What about these as surrounds
 
Are you guys really comparing JBL and M&K? :confused: I mean, that's not even a contest is it? And while we're at it, throw QSC into the mix, many in the film industry prefer those over the older JBLs. Or just go all in with some M2s. :D

@AFM1 - check out the QSCs! SC-1150 and SC-1120 ..I would have bought these if it wasn't for the JBLs coming up for me at a good price.
 
For my case my current XTZ S5 side surrounds have to go as they will be too close to the side seats so I need something slimmer (the issue is more squeezing between the speaker and the seat rather than an audio issue, though that is obviously still a consideration).
Food for thought... if you're really sitting so close that you have to minimize cabinet depth, you're likely sitting to close. Regular speaker designs don't work very well when sitting close. Ideally you want a time coherent point source (coax driver) for really short distances. Have you thought about going coax? Or maybe the below mentioned CBTs? 50 Model would probably be better for you.
What about these as surrounds
JBL used the smaller 50 model as sides/surrounds a few years back for full Synthesis demos with M2 in the front if I remember correctly. They certainly work well. CBT speakers, if properly designed make a step towards line sources. You'd get less than the 6dB drop per double distance. The advantage of the 70s vs 50s is they're slightly curved, so the upper part of the speaker has higher SPL than the lower part. This can be useful if you have multiple listeners in a row. You can aim to top part at the furthest away listening position and the lower part at the closest, which minimizes the SPL difference between seats. The rigid setup isn't perfect. Larger models are adjustable, so it's possible to achieve a 0dB difference in SPL between listening positions.

You can always go crazy...
 
Food for thought... if you're really sitting so close that you have to minimize cabinet depth, you're likely sitting to close. Regular speaker designs don't work very well when sitting close. Ideally you want a time coherent point source (coax driver) for really short distances. Have you thought about going coax? Or maybe the below mentioned CBTs? 50 Model would probably be better for you.

JBL used the smaller 50 model as sides/surrounds a few years back for full Synthesis demos with M2 in the front if I remember correctly. They certainly work well. CBT speakers, if properly designed make a step towards line sources. You'd get less than the 6dB drop per double distance. The advantage of the 70s vs 50s is they're slightly curved, so the upper part of the speaker has higher SPL than the lower part. This can be useful if you have multiple listeners in a row. You can aim to top part at the furthest away listening position and the lower part at the closest, which minimizes the SPL difference between seats. The rigid setup isn't perfect. Larger models are adjustable, so it's possible to achieve a 0dB difference in SPL between listening positions.

You can always go crazy...

Thanks StephanG & Lesmor - quite a clever design that. However, those CBT speakers are 9.3" deep, so nearly 24cm, which is deeper than my current speakers so they wouldn't work.

Like I said it's more a physical thing rather than an audio thing. The room is 3.51m wide and the front row is a 3-seater of around 2.51m wide. So it's 50cm from the edge of the seats to the side wall. As the door is in the back left corner you have to walk between the left side surround and the seats to get into the room. 50cm minus 24cm leaves a 26cm gap, which isn't all that generous and is asking for damage to the speaker as visitors squeeze past.

I'll mount the speakers at 95 degrees, so slightly behind the MLP, and at about 5 degrees higher than seated ear height, which will help with squeezing past, especially when the seats aren't reclined, and help a little with not firing right into their ears. Ear to side wall for the outside seats is about 88cm, so the shallower the speaker the more separation is maintained. Due to the closeness, I still feel a tripole would be better, but I'll try the JBL 8320s first and see how they go.

From a sound quality perspective, I don't really care all that much about the outside seats, as mostly it will be my wife there and she couldn't care less about the sound, but she would probably moan like billyo if the side surround was annoyingly loud right beside her, and the last thing I want is to be relegated to the side seats myself...
 
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Thanks StephanG - quite a clever design that. However, those CBT speakers are 9.3" deep, so nearly 24cm, which is deeper than my current speakers so they wouldn't work.

Like I said it's more a physical thing rather than an audio thing. The room is 3.51m wide and the front row is a 3-seater of around 2.51m wide. So it's 50cm from the edge of the seats to the side wall. As the door is in the back left corner you have to walk between the left side surround and the seats to get into the room. 50cm minus 24cm leaves a 26cm gap, which isn't all that generous and is asking for damage to the speaker as visitors squeeze past.

I'll mount the speakers at 95 degrees, so slightly behind the MLP, and at about 5 degrees higher than seated ear height, which will help with squeezing past, especially when the seats aren't reclined, and help a little with not firing right into their ears. Ear to side wall for the outside seats is about 88cm, so the shallower the speaker the more separation is maintained. Due to the closeness, I still feel a tripole would be better, but I'll try the JBL 8320s first and see how they go.

From a sound quality perspective, I don't really care all that much about the outside seats, as mostly it will be my wife there and she couldn't care less about the sound, but she would probably moan like billyo if the side surround was annoyingly loud right beside her, and the last thing I want is to be relegated to the side seats myself...
I suffer the same problem as you currently have DIYSG Volt 8s as my side surrounds so have to squeeze past(room is only 3.2m wide with 3 steat cinema chairs). Also I'm looking at upgrading my 4 surround to either matching JTR's. Will have the same issue with the size as they are even larger than my Volts. I've been considering these also:-



Speaker typeTime-coherent 5,25“ Coax One Point Source
PrincipleVented
SPL105dB Cont. / 108dB Peak
Frequency range85Hz to 20kHz (-3 dB)
Sensitivity88dB / 1W
Power rating / Impedance100W / 8 Ω
Width x Height x Depth250 x 400 x 75mm


or a lot more expensive I know:-



  • 3-way design
  • sealed cabinet, acoustic suspension design
  • THX Ultra rated
  • DPC treble/midrange array
  • 1x 26mm soft done HF unit
  • 2x 26mm soft dome midrange units
  • 1x 6.5" HPF bass drivers
  • 48Hz-32kHz at -10dB
  • 300Hz-20kHz at +/-1.5dB window
  • 86.5dB sensitivity
  • 109.5dB peak output
  • 4ohms nominal impedance (3.7 minimum)
  • 50-200w recommended amplifier power
  • H 378mm x W 230mm x D 173mm
  • available in piano black
  • £3,200 / pair

If I went for the cheaper Ascendo's, think they are about £500 each. I could change my volt heights at the same time. I'm in no rush probably leave it until 2024. I had KK Tripoles previously as side surrounds and after living with direct firing surrounds don't feel the need to go back to tripoles. I have them positioned again like you just behind the MLP, slightly above ear seated level.
 
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@AFM1

Could you fit the MK CS surrounds in your room/system?

I use a set of the CS29’s as rear surrounds in my room in accompany with some MK150T on walls and surrounds and the rear integration is brilliant.

I dont quite know how the CS work but they sound bloody brilliant and very convincing at placing sounds even though they’re sat on the floor.

They seem to command a quite a price but like I say very good speakers and if you don’t like them you could sell them on for little loss, however they aren’t that easy to come by either!
 
I run CS surrounds and M&K 850s as surround backs with my JBLs and the sound is seamless....
 
@Doug Pyper i can’t find where you posted the link to the PEQ filters. Pretty sure it was in this thread but can’t see them anywhere? 🤷‍♂️
 
@Doug Pyper i can’t find where you posted the link to the PEQ filters. Pretty sure it was in this thread but can’t see them anywhere? 🤷‍♂️
Is this the site you mean?


Go to menu, then EQ - it has filters for loads of speakers, generated from measurement data. Probably only worth using for speakers that have been measured anechoically or with a Klippel, so that the PEQ filters will be fairly reliable.
 

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