Geddes multiple subwoofer method - 3 subs vice 4

It is interesting how strongly bass affects our perception of audio. Owning the JBL 4367 I more or less agree Phusis take on them but will add my thoughts as this thread is about bass.

I have been using them with subs for the last year (60-65hz highpass) and recently got rid of my subs (sold one and gave one to a friend) in prep for new subs on order. With the subs the system as a whole is warm and impactful, I can play them very loud with no ear fatigue at all.

But without the subs the speakers seem a touch bright to me (they measure “flat” with a bit of HF roll off in my room). The interesting thing is the subs are the only change and they were measured and adjust flat to 25hz and roll off from there. Now that it has been a month or so without subs the speakers sound a touch warm again. All in all pretty interesting with no change to the mids or highs. Just that lass octave and 1/2.

I don’t have much horn experience other than these speakers and demos of the Klispch line (which I did not really care for if I am being honest). I sit 10’ from my speakers and a well damped room, 7” broad band panels at first reflection points, fully treated ceiling, full carpet, big soft fabric theater seats, so that might play into it too. My UHF adjustment is 0.5db down which makes a bigger difference than one might think.

The 4367 currently is my favorite speaker I have owned, their flaws are minor at their price point and have honestly given me a moment of pause as I am not sure what I would change too. which leads me to changing my subs and trying a more active approach and I plan to dip my toes into digital correction and see how it goes

Dear @deep_333 : My room geometry is not easy to use the Harman calculator, these are more or less the dimensions/shapes:

as I posted my apartment has 2 parlors from the entrance door. First parlor where is not seated the system its wall distance to the other extreme, where is the second parlor/listening area/system, are 9.70m to the window that’s behind the speakers.

Now the speakers are at 95cm. in front of the windows and the left speaker is at 30cm. from the side wall, the rigth wall is at 8.5m from the left one.

The center of the speaker tweeters in between are at 2.60m and the speaker woofers at 3.05m.

Listening area length is 4.70m and the wide is around 4.5m. Exist a passageway of 1m. wide by 14+m. in length. This apartment has 3 bedrooms and two complete bathrooms. All in one floor, so is a little big.

Dining room is big and the dining room central/rectangular table is for 10 seated people.

Both parlors are full of ( mainly ) wood furniture as the dining room and all around exist wood display cabinet ( like seven of them ). The parlor furniture are made from natural absorbtion materials and due to the shape of the wood furniture it works as difussors.

Rigth now the system is working truly fine and till today I think that I can’t do ( ? ) anything to improve its very high quality MUSIC reproduction and very high resolution.

It does not matters the SPLs the room/system just refuse to distort: MUSIC stage always is there/nothing change but SPL. Yes, its noise floor and distortions levels are so low that can be dangerous to the ears with out taking in count due that we can’t be aware of those distortion levels. No, I normally listen at around 82 or even a little lower db SPL and only during some kind of system audio items tests I listen at 95db with peacks at 105+db for only a few minutes.

@rauliruegas 

I'm having difficulty visualizing this with the written description. Do you have a top view sketch/schematic with distances, etc (that you can post here)? "Picture says a thousand words", Confucius said.

I’ve found them too "hot" sounding over longer durations in being more forward and incisive in their sonic nature than my own system. To by fair, in many ways the 4367’s are delightful speakers; exhilarating, energetic, honest, clean, extremely informative (I’d say a wee bit too "insisting") and - apart from the low octave shifting towards a warmer imprinting - fairly coherent.

The thing is though, to my ears and sensibilities they simply become too much over time, and moreover I find string instruments like violins to have a slightly "plastic"-like and/or nasal character to them (I prefer the M2’s and 4349’s here with their flatter waveguide), which is a dealbreaker to me. My EV main speakers by comparison with their large format horns + subs are sonically more akin to large panel speakers; more relaxed, less "beamy," fuller and more visceral/physical/dense. Where it becomes apparent they’re a larger package overall, apart from their more natural height of presentation, is at higher SPL’s (not least with movies) where the sheer unadulterated force and power is at full display.

 

...know about that "plastic’y" sound all too well and it goes all the way up to their top end line. The measurement heavy JBL/Harman PhDs don’t seem to care too much, as long as it measures great! They may need to put their big egos down and learn a thing or two from the likes of Borresen, Yamaha, TAD, etc.

What horn subwoofers do you use? DIY? or something else? I might be interested in getting one.

Dear @m-db  : " on a used Plus in any size I think you might be amazed. "

hings are that I already had the DD Plus experience not in a home system but with an audio distributor. Rally good.

However the pulp/paper cone of my HGS ones are the ideal for my speaker woofers where the DD driver build material is different with a different bass reproduction signature. Thank's for your advise.

R.

@deep_333 wrote:

What horn subwoofers do you use? DIY? or something else? I might be interested in getting one.

They’re the tapped horn principle, DIY and called MicroWrecker (a sibling to the LilWrecker tapped horn, which has a 5Hz lower tune for a 50% addition in volume (30cf.) and ~3-4dB hit in sensitivity). I got the plans over at AVS Forum from a developer there, and had them built by a cabinet maker. The developer also simulated drivers for the specific design in the Akabak (or Hornresp) software, and so had a range of suitable woofer choices to go with. These have to have the proper electromechanical parameters within a fairly narrow window in a given tapped horn design for them to work the best here, which is to say to properly resonate the horn; too weak a motor and the horn isn’t "excited" enough, and too powerful a motor will compress the air too severely at the throat, also leading to insufficient horn resonation. The B&C 15TBX100 (8 ohm) unit I’m using sits right in the middle of the desired performance window here, and so is close to the ideal driver for the purpose. Close, because it lacks the very last bit of excursion range to be fully exploited at its rated power (1000W nominal power handling, 2 hour pink noise test, free air) before hitting Xmax in this design with a ~23Hz tune, but it’ll take 600W up until that point, so perhaps a theoretical 2dB SPL subtraction overall. Fine with me, as a single MW will still do over 120dB’s down to 25Hz with the B&C unit, and I have two of them - corner mounted. The same driver is used in Danley’s TH-115 subs, but being this tapped horn design has a higher tune the driver can be used at full power here.

Size of speakers doesn’t seem to scare you off, but be aware it’s still a 20cf. volume per cab. When you see them "in the flesh" it can a bit unsettling getting a feel for their true size, I know it was for me at first. In the same ballpark there’s also great designs by Josh Ricci over at Databass.com, notably the Skrams, Skhorns and Othorns. The latter is also a tapped horn, though built around the 21" B&C 21SW152 woofer - a beast - and with a ~28Hz tune. Initially I intended to have a pair of the Othorns built, but the woofers were out of stock for months, and so I opted for the MW’s. The Skrams are a great design as well, and more driver "friendly" than the Othorn. Meaning, a range of 21" pro woofers can be used here, whereas the Othorns are only fully pleased with named woofer or its IPAL equivalent.

The inspiration for the MW’s were Danley’s TH-50 tapped horn, and they’re very much alike in vital areas. Josh Ricci opted to develop the Gjallarhorn tapped horns instead (also inspired by the TH-50), which is built around TC Sounds LMS-Ultra 5400 driver (18"), but that driver is no longer built. A beast of a sub, and about the most one can squeeze out of an 18" woofer, I’m told. They’re tuned a bit lower than the MW’s, but I never truly considered them as they are too monstrously sized (plus more than 300 pounds w/driver) and a bit hampered in their upper range due to the slightly lower tune.

In any case any of the above designs are extremely capable in putting out high quality bass at prodigious SPL’s and low distortion levels - certainly compared to most any low eff. "hifi" subs out there.