General Speaker Advice and Recommendations

Everything sounds better at higher SPL's. Unless it's a crappy design with woofer breakups sticking out, tweeters crossed too low/shallow and ports chuffing.

 

Would this thread be the right place too look for some answer on freq-response questions?
I have an "impressive" dip between 300 - 100 hz that I would like to troubleshoot.
Something is sucking the energery in that area and I am at a loss as too find the cause.
Is this a floorbounce dip?
Edit: That is the average freq response from 9 measurement positions in a radius of 2.4 m X 1.2 m for the right speaker.

 

True, I should have qualified that this was compared to a few other bookshelf speakers I’ve owned recently including my Dynaudios. The difference isn’t huge, but the Dyns for instance I find a bit more lively at low vol - they are a rear ported speaker.

 

Try taking extra measurements further and closer from the listening position.

 

That is the average freq response from 9 measurement positions in a radius of 2.4 m X 1.2 m

 

Ok, cool - next time mention what we're seeing! I recon it's the stereo output? If so, measure one channel around 1m from the driver. This way we can rule out the speaker itself. Then you can try EQ-ing the dip out and see wether that helps. The dip seems to consist of two nulls. Floor bounce nulls suck, but very rarely you get a perfect destructive interference. Sound has many ways of reaching your listening spot, so by boosting you're still increasing the signal that has a way to reach you.

 

There is more to it.
I'll add AB amp transitioning out of A zone, thermal compression, excursion based artefacts.

However I would rephrase it differently:
Most modern low eff speakers navigate around these problems by being just dull and safe in these regards, not letting you to have the benefits in low power levels. Heavy super damped cones, thick spider/surround, resulting low eff + super high excursion. This needs to be lit up by gunpowder to liven up at all.

 

Does that mean that you are able to tell when your class A/B amp goes from class A mode to class B mode while listening to music?

Chapeau

 

I believe so. It depends on how good or bad the output stage is. The way the new Schiit tech is set up and a few others might be a lot harder to detect. Crossover distortion is the thing. In a perfect OTS there would be none. Fortunately, things are moving to that direction.
I can hear a distinct change in subtle details from my Genelecs semi loud vs moderate.
There are numerous resources online to illustrate this with more than listening impressions.
Mr Pass has looked deep down to that particular rabbit hole for one.

 

I like dynaudio...
never heard PMC or Proac. Amphion are incredibly accurate, best imaging ive heard/had, fast transients, detailed. Soft treble. Sadly, the one18 just didnt have enough bass. I only have the small ATC and I really cannot afford the bigger models. im very interested in the scm40 v2. ive heard them and the scm19. I personally didnt really like the atc scm19 especially at the price they go for.

after having had many "top" bookshelf speakers and many BIG speakers sporting 12 inch or 15 inch woofers, I can say that I just dont care anymore about any speakers that has a 6.5 inch woofer/midbass or smaller.

5 inch or 6.5 inchers trying to do bass just sound too compromised in bass quality for me to consider those models no matter how good the mids/treble. so im afraid that rules out most of Proac, PMC, Dynaudio.

sadly, big pmc or big atc or big amphion is big money.

 

Thanks, yeah those ATCs really escalate in pricing once you start getting into the three-ways.

How would you characterise the differences between the SCM11 and SCM19, how much better is that Super Linear mid/bass? I’m even considering the SCM20SL (not to be confused with the pro version) as a buy and never look back option. Though as far as I can tell for twice the money of the SCM19 the differences are an upgrade from their standard soft dome tweeter to their Super tweeter with a larger motor and surface area, a smaller and I expect better enclosure, and supposedly a more studio style voicing. Can’t find a single comparison online of the most recent versions with the ATC made tweeters.

I wish I had the space for floor standers, after my experience with the BK Electronics XLS200mk2 subwoofer, LCD2C, Utopia and reading comments here I can see that subwoofers do not produce fast good quality bass in the regions a bookshelf would need the support. Not that I have the space for that either.

 

I’m sure murphy will give you his experience with them, but the main differences for me were bass and soundstage. The 11s were quick and punchy as hell in the bass (probably the fastest bass I’ve ever heard) but I found them almost too quick to the point of sounding unrealistic. Just too energetic. This may have been simply because they didn’t go low enough. The 19s go lower (lower than the specs imply) and just sound more relaxed, natural and powerful, but still very quick with fantastic dynamics. They are the most dynamic sounding speaker I’ve ever owned. They are difficult to pair a sub with however because they are still so quick and dynamic. My Rel T7i sub can just barely keep up (and really, doesn’t sound like it can keep up, but it does the job for now).

Also I found the soundstage on the 11s to be lacking - very small/narrow, at least in my room. The 19s sound much larger and more open for whatever reason - this may be due to the SL midbass driver, not sure.

 

scm20/scm19 end game... I dont think that the bass of any 6 incher can be considered engame. in the mids/treble, sure. but like Rlow said, he need a subwoofer.
And personally, I dont find they integrate as easily and well as id like. and even then, extension is covered by a subwoofer, but take the scm19 that go down to 60hz, well its a 6 incher that takecare of the bass freq from 60hz to 250hz. a 6 inch covering the bass sounds very small, the bass wont really have the impact of even a 8 inch.

I personally would not go back to anything smaller then a 8 inch doing bass duty, and even my harbeth shl5+ bass leave lots to be desired compared to my genelec 1037b in the living room using a 12 inch woofer. 6 inch + sub will have great extension, but lack serious impact from 60hz to 120hz

 

A half decent mid-bass or pure mid driver is a lot 'faster' sounding than any conventional sub. I mean everything short of a square meter of radiating area for 20 Hz.
I strongly believe in that a matching bass driver needs to be made out of the same dna as the midrange.
Very little moving mass to radiating area. Coupled with a strong motor this will result in a 'fast' driver (with quite some quirks). A 10'' to 15'' would still only play down to some 40..45 Hz -3db in bass reflex box in an effortless manner, unless it's 2x 18'' and brute equalizing force is used, then lower.
So many big dynamic sounding 3-way speakers won't have a lot of bass extension, barely more than 8''+1'' two-way monitors. Goes to show that the 3-ways are more tuned by ear and 2-way monitors tuned by measurements.

 

I also think a reason subwoofers generally sound "slow" is because the way subwoofers are integrated almost always causes group delay in the bass region to rise. Since subs often only have a very narrow passband, say 20Hz to 60Hz and people often use very steep filters for the monitors and the sub, the group delay can be pretty significant. I don't think the group delay from a well designed port is as bad as the sub, especially since a port will usually be tuned to the subbass where it's not as important while the crossover for the sub usually happens in the midbass.

I modeled an asymmetric sub/monitor crossover with very shallow slopes a while back. The FR didn't look as flat as the steeper crossover, but the group delay and step response looked much better. Could be interesting to try that, but at that point time alignment starts to matter with a sub, too. It's much easier to just use a DSP for both the sub and the speakers at that point.

 

@murphythecat Endgame was implied only in the context of being limited to bookshelves. Sorry to prod you, but how come you didn’t like the SCM19 over the 11?

@rlow Thanks, was just reading back and saw that you had mentioned both the ATCs. I also see that you have the Dynaudio Special Forty. If not for the rear port they’d be very high on my list. Only thing I’ve seen so far with neodymium magnets in the mid/wooofer that weren’t approaching double the price, and one of the increasingly few soft dome options as you move up the ranges in the UK. How would you describe it’s presentation and performance vs the SCM11 and SCM19?

Can you elaborate on what those quirks would be, please?


‘Couple questions for you guys:
1. Which, if any, subwoofers are considered faster than most others, what design traits tend to effect speed, and how does sealed vs ported and the driver direction effect this trait?
2. As of now I’m leaning away from anything with metal dome tweeters for their fatigueing and/or harsh reputation. How would you guys characterise diamond dome and ribbon tweeters?

 

Large lightweight cone with strong motor behaves anything but a perfect piston in most of it's operating range.
It can either be light and stiff => massive harsh cone breakup or
it can be light and moderately stiff with moderate internal damping => wobble and moderate breakup (irregularities in impedance graph in midbass).
Eminence is good example of 15'' .. 18'' lightweight cone use, lots of cone breakup and lots of wobble in the high bass range due to not stiff enough cone.
No free meal in this.
edit: it's a spectrum: there is wide choice from super light (Eminence, Faital, RCF etc pro audio) --> half way (most common commercial hi-fi stuff) --> to sledgehammer (ht subs, Dayton Audio, car subs)

Regarding metal domes: It's more a myth nowadays that these sound harsh.
You can certainly find poor example that still do that.
The likes of Scanspeak, SBA, Seas etc, good brands; I don't think you'll find one on their portfolio.
It used to be the case with pioneering era hard domes more or less, so I have read/heard.
It's more so the filters or electronics that do that. Diamond domes do sound super real.
But for fidelity and resolution better soft domes don't loose out much, it's the transient characteristic thing the most and
there is different timber quality to them.
Again, I think the matching of midrange and tweeter is quite important for material, dispersion and right xo point.

 

I find speed to be a misleading term to use when talking about bass. Reduced to an absurd it will always point to tweeters being the perfect transducers for any frequency. Many think that a perfect sub should be able to turn on a dime and play a 20Hz square wave with nice square edges. Well, guess what - a perfect square wave at any frequency contains the fundamental sine and an infinite number of harmonic sine waves piled on top. See here -



Two to four octaves of bandwidth traditionally relegated to a bass driver is hardly a square wave. What's usually meant by speed is a clean output without any excess overhang, which corresponds to system damping, rather than driver speed. And a lack of HD, naturally.

As for subwoofer construction... If you can accommodate the size, go for a ported box with a very low tuning (mid-low twenties). This way you get the superior time response of a closed box over a wide bandwidth and only down low the port will take over with all of the negatives inaudible and/or masked by the room.

I wouldn't sweat over driver materials. It's only natural to associate the material with certain type of sound. However, material sound only comes in around the breakup region. As a rule of thumb, stiff cones/domes break up louder, but in a narrow region - the opposite is true of soft cones/domes. With proper filter design breakup can and should be rendered inaudible.

 

Not sure if this is the right location for speaker impressions?

This is a short review of a friends system: k2 s9500!
I first heard his system before the update and briefly mentioned it here:

He was at the time using Antipodes music server > accuphase dc-37 dac > coincident RC line stage pre amp > accuphase A 46 amp and some vintage JBL c60 (1970s)



He has since upgraded to an interesting speaker - JBL k2 s9500 (Early 1990s) which shares a similar compression driver to the c60 and dual 14 inch woofers! I have been interested in this development in his gear as I am hoping to pick up the JBL 4367 in two weeks, which has a more sophisticated wave-guide, compression driver and larger woofer but shares some design similarities. As you will likely notice he has also swapped up his pre-amp for an audio research from the coincident line stage (a pre-amp I think punches well above its price point).



Something that is very apparent is the craftsmanship which is "the spare no expense approach". The four modules per channel weigh 200kg (440lbs) each! That does include the massive concrete slab which is apparently to absorb the last bit of cabinet resonance. The wave guide is mirror finish steel and weighs 60kb (130lbs)!! The mdf cabinet is very well constructed and beautifully finished, I much prefer the gloss finish to the wood finish. There was giant gold binding posts connecting all the components, however he has switched it out for some designer cables.



So, how do they sound?

He is running a REL No.25 subwoofer - it was crossing over at 20hz, the bass emphasis, extension and resolution in the bass was nuts. I could really hear the bass guitar notes vibrating at incredibly low frequency.

The k2 s9500 seems a bit laid back, a bit soft, lacks upper mid extension, is not lively or engaging. Stage and imaging is really good but the lack of air is really noticeable with percussion instruments. With vocals and some solo classical stuff it was hard to fault but as soon as some brighter instruments were introduced everything started to sound a bit dull, compressed and bloated sounding. He really loves this, he retired the c60 because he found it a bit too lively and bright for him. I thought the c60 was the better speaker by a decent margin. I also think they played nicer with his room, he has only had a few weeks to dial them in but the room felt very small with the k2 and fine with the c60. I wanted to take about 10 steps back but couldn't.


Maybe the AR pre-amp is a lot warmer than his coincident pre, otherwise his system was the same as when I last heard it.

I'm heading down the the Melbourne audio show on the 12th, I'm hoping to hear the 4367 one more time before buying them at show price. I remember them to be dynamic, lively and more resolving than these k2 s9500 (you would hope so after nearly 30 years of improvement), however the current model jbls are crafted for a fraction of a price of what these k2s were. I did compare the new k2 s9900 to the 4367 at the show last year and found I preferred the 4367.

 

definitely, a 12 inch 3 way might not really get much lower then 2 way 8 inch, but so far, all 12 inch 3 way have the quality in the bass that is simply in another level even compared to a 8 inch. id say a 6.5 inch woofer will sound in the bass literally 2 times less even though the FR is flat down to 50hz for both 8 and 6 inch based 2 way.

im not sure about the material of the woofer matching the mids, bass frequency are so much coloured by the room that im perplexe, if the woofer is not crossed to high, as to how much you can know if its a metal or paper cone.

it seems to be a myth that a bigger woofer will be slower then a smaller. in most case, the motor of a big woofer is bigger even proportional to the cone diameter. anyways, another story