Official JTR Speakers Subwoofer Thread - Page 284 - AVS Forum | Home Theater Discussions And Reviews
Forum Jump: 
 17900Likes
Reply
 
Thread Tools
post #8491 of 12958 Old 06-01-2018, 10:14 AM
AVS Forum Addicted Member
 
beastaudio's Avatar
 
Join Date: Dec 2010
Location: Western NC
Posts: 14,439
Mentioned: 396 Post(s)
Tagged: 1 Thread(s)
Quoted: 5538 Post(s)
Liked: 5367
Quote:
Originally Posted by 04rex View Post
Quick question regarding XLR cables. I will be going from the ART cleanbox to 1 S2, then from the S2 to the 2nd S2. Would I essentially need 2 XLR cables with a male and female on each end? I will probably be getting the Monoprice higher end ones. Forget what they are called.

Thanks!
With your anthem, and the s1, you shouldn't need a cleanbox. ESPECIALLY considering that even the cleanbox pro starts to roll off at 20hz, you are robbing your excellent sealed enclosure of the lower frequencies. There is a mod that can be done to the Art CB pro, but not sure you want to go down that path. There are other so called "bump boxes" That don't show this same rolloff if you are interested. THe henry matchbox HD would be one of them, and the samson s-convert would be another if you can manage to find one. Back to my original point however, you absolutely shouldn't need a bump box with the particular components you will be using.
Marc Alexander likes this.

European Models do not accept banana plugs
Belly of the Beast: Bass Bunker Theater
beastaudio is offline  
Sponsored Links
Advertisement
 
post #8492 of 12958 Old 06-01-2018, 10:26 AM
AVS Forum Special Member
 
04rex's Avatar
 
Join Date: Nov 2010
Location: London, Canada
Posts: 1,042
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 330 Post(s)
Liked: 64
Quote:
Originally Posted by beastaudio View Post
With your anthem, and the s1, you shouldn't need a cleanbox. ESPECIALLY considering that even the cleanbox pro starts to roll off at 20hz, you are robbing your excellent sealed enclosure of the lower frequencies. There is a mod that can be done to the Art CB pro, but not sure you want to go down that path. There are other so called "bump boxes" That don't show this same rolloff if you are interested. THe henry matchbox HD would be one of them, and the samson s-convert would be another if you can manage to find one. Back to my original point however, you absolutely shouldn't need a bump box with the particular components you will be using.
Thanks for the info. My reasoning is that it will be a fairly long run, more than 35ft, I want to avoid any kind of hum that may happen as best as I can, I am planning to hopefully one day upgrade to a Pre/Pro, and I already have the ART Cleanbox so why not use it. But if it is going to limit the lower frequencies then that isn't good either.

Decisions, decisions. To get a long run, good quality RCA cable is also a lot of money.

FAMILY ROOM - Totem Tribe II LCR, JL Audio E-112, Anthem MRX 720, Apple TV, WD HDTV, Panasonic 55" Plasma
BASEMENT THEATRE - Paradigm Studio 100 v5, 690 v5, 10x4 v5, Anthem AVM 60, Outlaw Audio 7700 & 7125, 2x JTR Captivator S2s, X-Box One X, Apple TV 4K, HTPC, JVC NX-5, 106" screen
04rex is offline  
post #8493 of 12958 Old 06-01-2018, 10:26 AM
AVS Forum Special Member
 
Join Date: Aug 2016
Posts: 1,674
Mentioned: 27 Post(s)
Tagged: 0 Thread(s)
Quoted: 1012 Post(s)
Liked: 1261
I could see him using a bumpbox if the Anthem isnt grounded and he's getting a ground loop via RCA on the S2s.

My vote is for the Henry Matchbox HD as well (if needed) but its a significant premium from the cleanbox.
Pradeep2 is offline  
Sponsored Links
Advertisement
 
post #8494 of 12958 Old 06-01-2018, 10:40 AM
AVS Forum Addicted Member
 
beastaudio's Avatar
 
Join Date: Dec 2010
Location: Western NC
Posts: 14,439
Mentioned: 396 Post(s)
Tagged: 1 Thread(s)
Quoted: 5538 Post(s)
Liked: 5367
Quote:
Originally Posted by 04rex View Post
Thanks for the info. My reasoning is that it will be a fairly long run, more than 35ft, I want to avoid any kind of hum that may happen as best as I can, I am planning to hopefully one day upgrade to a Pre/Pro, and I already have the ART Cleanbox so why not use it. But if it is going to limit the lower frequencies then that isn't good either.

Decisions, decisions. To get a long run, good quality RCA cable is also a lot of money.
Quote:
Originally Posted by Pradeep2 View Post
I could see him using a bumpbox if the Anthem isnt grounded and he's getting a ground loop via RCA on the S2s.

My vote is for the Henry Matchbox HD as well (if needed) but its a significant premium from the cleanbox.
Or just get a pair of these: https://www.amazon.com/dp/B000068O4G..._t1_B000068O4D

And then a pair of the xlr female to rca male for the other end if you don't want to use the XLR in on the s1 and use the xlr cables of your choice. You'll already be set to jet when and if you transition to separates with XLR inputs...

European Models do not accept banana plugs
Belly of the Beast: Bass Bunker Theater
beastaudio is offline  
post #8495 of 12958 Old 06-01-2018, 10:42 AM
AVS ***** Member
 
mthomas47's Avatar
 
Join Date: Nov 2007
Posts: 8,187
Mentioned: 331 Post(s)
Tagged: 0 Thread(s)
Quoted: 5424 Post(s)
Liked: 10208
Quote:
Originally Posted by Lorderl View Post
Take it FWIW coming from a newb. Reading a bit between the lines of some post, words like "fine", "acceptable", tends to suggest less than enthusiastic number results in the mid-base range.

TBH, when I first heard of the 10hz tuning I was expecting 100db - 100.4db @10hz and the mid-base to be more inline/equal to the Cap1400. Nonetheless I'm sure i'll be totally happy with my 10hz Cap240ULF.


Quote:
Originally Posted by chucky7 View Post
I think I am just spoiled by JTR... I was expecting output somewhere between the 4000ULF and the 1400, as it is priced that way. Make no mistake, Jeff is still the only one doing a 165lb, 10Hz tuned ported sub. It's just that Jeff raised the bar so high...

The 4000ULF hit 115dB at my MLP 13 ft from it. Therefore, with the 10Hz tuned 2400ULF 5.5ft from the MLP, you should be getting at least 105dB, assuming the MLP is not in a null.

Hi,

I think this is a very complicated issue, which isn't always easy to explain. But, you read what MKtheater said about high mid-bass SPL. How many of us really want to listen to any content at 130db? And, how many of us will still have normal hearing a year from now if we do?

If a single Cap 2400 averages about 119db in the mid-bass frequencies outdoors, then it should average at least about 3db more than that indoors, due to boundary gain. And, those measurements were taken at 2m, so you should still be pretty close to 120db at a listening distance of 12' or 13'. (Indoors, SPL drops about 3db per doubling of distance.) 120db is Reference, even with an extra 5db factored in for the extra channels in an HT system. (115db peak volume for the LFE channel + 5db for subwoofer support for the other channels at 105db peak volume.) And, those are just peaks. Most content won't be nearly that loud.

Where it starts to get really complicated is in factoring in the effects of room gain. Different size rooms will have different amounts at different frequencies. In Chucky's room, for instance, if he gets 115db at 10Hz from his Cap 4000, at a distance of 12', then he is getting about 10db of room gain at 10Hz - a 3db loss from distance. (108 + 10 - 3 = 115)

The next place I think that the whole thing gets dicier is when we try to decide at what frequencies sound pressure levels are in equilibrium. And, I suspect that will depend somewhat on our individual perceptions. In theory, the Cap 2400 with the lower port tune, and the more modest mid-bass, may sound more in equilibrium than the earlier version with the 14Hz port tune. But, even with the earlier version, owners have the LFA (low-frequency adjust) feature to help balance the sound between mid-bass and low-bass.

FWIW, I think that numerical drag racing aside, either version of the Cap 2400 will be an excellent all-around performer, and there will be very little to choose between them.

Regards,
Mike
chucky7, MKtheater, toddct and 1 others like this.

GUIDE TO SUBWOOFER CALIBRATION AND BASS PREFERENCES

* The Guide linked above is a comprehensive guide to Audio & HT systems, including:
Speaker placements & Room treatments; HT calibration & Room EQ; Room gain; Bass
Preferences; Subwoofer Buyer's Guide: Sealed/ported; ID subs; Subwoofer placement.
mthomas47 is offline  
post #8496 of 12958 Old 06-01-2018, 11:35 AM
AVS Forum Special Member
 
04rex's Avatar
 
Join Date: Nov 2010
Location: London, Canada
Posts: 1,042
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 330 Post(s)
Liked: 64
Quote:
Originally Posted by beastaudio View Post
Or just get a pair of these: https://www.amazon.com/dp/B000068O4G..._t1_B000068O4D

And then a pair of the xlr female to rca male for the other end if you don't want to use the XLR in on the s1 and use the xlr cables of your choice. You'll already be set to jet when and if you transition to separates with XLR inputs...
These came up before, but it was said that the signal will still be unbalanced as the connector is still RCA. That's why I should use the Cleanbox.

FAMILY ROOM - Totem Tribe II LCR, JL Audio E-112, Anthem MRX 720, Apple TV, WD HDTV, Panasonic 55" Plasma
BASEMENT THEATRE - Paradigm Studio 100 v5, 690 v5, 10x4 v5, Anthem AVM 60, Outlaw Audio 7700 & 7125, 2x JTR Captivator S2s, X-Box One X, Apple TV 4K, HTPC, JVC NX-5, 106" screen
04rex is offline  
post #8497 of 12958 Old 06-01-2018, 11:52 AM
Member
 
Lorderl's Avatar
 
Join Date: Jun 2009
Location: New Haven, CT
Posts: 172
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 102 Post(s)
Liked: 50
Quote:
Originally Posted by mthomas47 View Post
Hi,

I think this is a very complicated issue, which isn't always easy to explain. But, you read what MKtheater said about high mid-bass SPL. How many of us really want to listen to any content at 130db? And, how many of us will still have normal hearing a year from now if we do?

If a single Cap 2400 averages about 119db in the mid-bass frequencies outdoors, then it should average at least about 3db more than that indoors, due to boundary gain. And, those measurements were taken at 2m, so you should still be pretty close to 120db at a listening distance of 12' or 13'. (Indoors, SPL drops about 3db per doubling of distance.) 120db is Reference, even with an extra 5db factored in for the extra channels in an HT system. (115db peak volume for the LFE channel + 5db for subwoofer support for the other channels at 105db peak volume.) And, those are just peaks. Most content won't be nearly that loud.

Where it starts to get really complicated is in factoring in the effects of room gain. Different size rooms will have different amounts at different frequencies. In Chucky's room, for instance, if he gets 115db at 10Hz from his Cap 4000, at a distance of 12', then he is getting about 10db of room gain at 10Hz - a 3db loss from distance. (108 + 10 - 3 = 115)

The next place I think that the whole thing gets dicier is when we try to decide at what frequencies sound pressure levels are in equilibrium. And, I suspect that will depend somewhat on our individual perceptions. In theory, the Cap 2400 with the lower port tune, and the more modest mid-bass, may sound more in equilibrium than the earlier version with the 14Hz port tune. But, even with the earlier version, owners have the LFA (low-frequency adjust) feature to help balance the sound between mid-bass and low-bass.

FWIW, I think that numerical drag racing aside, either version of the Cap 2400 will be an excellent all-around performer, and there will be very little to choose between them.

Regards,
Mike
I get it that I won't be playing at insane levels but wouldn't the few extra db's in the mid-range mean even less distortion (even though it already plays cleanly) at a normal listening level? I know its academic as the Cap2400 will be great.


"Numerical drag racing", LOL, I like that phrase.
mthomas47 likes this.

Display: Samsung LN55B650
AVR: Denon 2809ci
Players: OPPO BDP-83 || Streaming: Amazon Fire TV || Kindle Fire HD8
Speakers: Paradigm Studio 20v3 || CC-570v3 || ADP-470v3
Sub: JTR Captivator 2400ULF-10hz
Lorderl is offline  
post #8498 of 12958 Old 06-01-2018, 01:05 PM
AVS Forum Addicted Member
 
Marc Alexander's Avatar
 
Join Date: Aug 2001
Location: Inland Empire, CA
Posts: 13,336
Mentioned: 231 Post(s)
Tagged: 0 Thread(s)
Quoted: 5333 Post(s)
Liked: 4835
Everyone seems to be a) assuming or accepting that the 2400 has less output in the mid-bass than the 1400 and that b) it was a conscious decision Jeff made to gain ULF output at the expense of the mid-bass. He did not. I spoke to him about it last week when data-bass had first posted the measurements (but not the notes so the link was hidden). The ambient temperature and sun are likely is to blame for the low numbers. It also seems to matter what direction measurements are taken. 10Hz up or 125Hz down.

Like I said earlier, numbers can be very deceiving. The 2400s output should exceed the 1400 across the board, except maybe at the 1400's tuning region. If @chucky7 will bring his 1400 over tomorrow I can prove this. I am going to capture data with REW [in addition to Clio] so that anyone can load the measurements.

I think comparisons are useful in the right context. The "PSA Output Factor" charts were very conterversial. The recent Chucky chart comparing the PSA sealed subs to JTR were no better IMHO. I'd love to help Chucky portray a more accurate picture. The charts shouldn't be used for purposes of JTR bragging rights/cheerleading vs other brands. They should be tools to help all of us, the consumers and the trusted advisors (like @mthomas47 and others) who make recommendations. JMO
Marc Alexander is online now  
post #8499 of 12958 Old 06-01-2018, 01:13 PM
AVS Forum Addicted Member
 
Marc Alexander's Avatar
 
Join Date: Aug 2001
Location: Inland Empire, CA
Posts: 13,336
Mentioned: 231 Post(s)
Tagged: 0 Thread(s)
Quoted: 5333 Post(s)
Liked: 4835
Quote:
Originally Posted by beastaudio View Post
With your anthem, and the s1, you shouldn't need a cleanbox. ESPECIALLY considering that even the cleanbox pro starts to roll off at 20hz, you are robbing your excellent sealed enclosure of the lower frequencies. There is a mod that can be done to the Art CB pro, but not sure you want to go down that path. There are other so called "bump boxes" That don't show this same rolloff if you are interested. THe henry matchbox HD would be one of them, and the samson s-convert would be another if you can manage to find one. Back to my original point however, you absolutely shouldn't need a bump box with the particular components you will be using.
How significant is the roll off? Perhaps it can be compensated for?
Quote:
Originally Posted by beastaudio View Post
Or just get a pair of these: https://www.amazon.com/dp/B000068O4G..._t1_B000068O4D

And then a pair of the xlr female to rca male for the other end if you don't want to use the XLR in on the s1 and use the xlr cables of your choice. You'll already be set to jet when and if you transition to separates with XLR inputs...
This is a good approach that is worth a try. You may not need balanced. If you don't experience noise you are good to go!
Marc Alexander is online now  
post #8500 of 12958 Old 06-01-2018, 01:17 PM
AVS Forum Addicted Member
 
Marc Alexander's Avatar
 
Join Date: Aug 2001
Location: Inland Empire, CA
Posts: 13,336
Mentioned: 231 Post(s)
Tagged: 0 Thread(s)
Quoted: 5333 Post(s)
Liked: 4835
Quote:
Originally Posted by Lorderl View Post
I get it that I won't be playing at insane levels but wouldn't the few extra db's in the mid-range mean even less distortion (even though it already plays cleanly) at a normal listening level? I know its academic as the Cap2400 will be great.
Yes!

I truly believe this narrative that the 2400 is giving up anything to the 1400 is not accurate.
Marc Alexander is online now  
post #8501 of 12958 Old 06-01-2018, 01:17 PM
AVS Forum Addicted Member
 
MKtheater's Avatar
 
Join Date: Jul 2006
Location: New Hartford, NY
Posts: 18,483
Mentioned: 135 Post(s)
Tagged: 0 Thread(s)
Quoted: 2427 Post(s)
Liked: 2407
Ricci mentioned that the 2400ulf was half the 4000ulf. That should say it all. I see numbers that don’t jive from DB Ati home and it is because of all the factors involved. A simple measurement does not tell the whole picture.
Marc Alexander likes this.

Nothing right now
MKtheater is offline  
post #8502 of 12958 Old 06-01-2018, 02:00 PM
Member
 
Lorderl's Avatar
 
Join Date: Jun 2009
Location: New Haven, CT
Posts: 172
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 102 Post(s)
Liked: 50
Quote:
Originally Posted by Marc Alexander View Post
Everyone seems to be a) assuming or accepting that the 2400 has less output in the mid-bass than the 1400 and that b) it was a conscious decision Jeff made to gain ULF output at the expense of the mid-bass. He did not. I spoke to him about it last week when data-bass had first posted the measurements (but not the notes so the link was hidden). The ambient temperature and sun are likely is to blame for the low numbers. It also seems to matter what direction measurements are taken. 10Hz up or 125Hz down.

Like I said earlier, numbers can be very deceiving. The 2400s output should exceed the 1400 across the board, except maybe at the 1400's tuning region.
Quote:
Originally Posted by Marc Alexander View Post
Yes!

I truly believe this narrative that the 2400 is giving up anything to the 1400 is not accurate.
Thanks for this. Hopefully @Jeff Permanian can clarify this when he makes his announcement today by including his in-house numbers for the 10hz Cap2400.

Display: Samsung LN55B650
AVR: Denon 2809ci
Players: OPPO BDP-83 || Streaming: Amazon Fire TV || Kindle Fire HD8
Speakers: Paradigm Studio 20v3 || CC-570v3 || ADP-470v3
Sub: JTR Captivator 2400ULF-10hz
Lorderl is offline  
post #8503 of 12958 Old 06-01-2018, 02:18 PM
AVS Forum Special Member
 
imureh's Avatar
 
Join Date: Mar 2009
Location: Houston, TX
Posts: 4,360
Mentioned: 201 Post(s)
Tagged: 0 Thread(s)
Quoted: 2728 Post(s)
Liked: 3297
@Marc Alexander , just for my education, the temperature point intrigues me. I had not heard much about it in past comparisons and I wonder how would ever any of the measurements done by Ricci would be under the same conditions? Does that not render all the comparisons at data-bass useless since they were all done under different conditions? I am sure they make a difference but doubt they are audible? Just keen to understand this issue as I think it’s negligible IMO.

Subwoofers: Dual Rythmik FV18s Rev2 with Paper cone, BOSS Platform mini riser
Speakers: PSA MTM-210 L/C/R - Klipsch 250S Surrounds, PSA MT 110sr Rear Surrounds, 4 x SVS Prime Elevation for Atmos
Video: Epson PowerLite Home Cinema 6500 UB; Room: 2100 cuft sealed on suspended floor
Receiver & Players: Denon X4400H, Oppo UDP-203, Roku Ultra. Apple TV, Minidsp 2X4 HD
imureh is offline  
post #8504 of 12958 Old 06-01-2018, 03:05 PM
AVS Forum Special Member
 
Ricci's Avatar
 
Join Date: Mar 2007
Location: Louisville KY
Posts: 5,485
Mentioned: 166 Post(s)
Tagged: 0 Thread(s)
Quoted: 382 Post(s)
Liked: 895
Well I'm glad that this has resulted in a spirited discussion at least.
Where to even begin regarding all this speculation...


1.)As far as I know there will be both a regular Cap 2400 with tuning like the 1400, and the 2400-ULF which will be a bigger cab tuned much lower. To my recollection this is what Jeff has told me. 2 different subs.
Also to the best of my recollection the drivers are different. I was told that the 4000 drivers are not the same as those in the 1400. The measurements alone show that. I'm not entirely sure that the 2400-ULF driver is the same build as the 4000 but it would make sense that it is. It may have been updated or changed a bit in the meantime since the 4000 test that was posted. Jeff does tweak his drivers a LOT. This is not to mention that drivers from even the same batch can vary quite a bit in performance. He will have to confirm much of this.


2.)Estimates of how something might perform are just that. I added 150 more Hp with a supercharger so I should be able to drop my 1/4 mile ET by a full second. Maybe. Maybe not. It's a complex interaction of many components and the assumption is a gross simplification. Perhaps the traction needed to put that power down isn't available.
Comparing amplifier power ratings is similar. Wattage is rated into a purely resistive load at a nice even 2, 4 or 8 ohms usually. Speakers behave nothing like this. In most cases it is a lot more useful to look at the maximum voltage and amperage available from the amplifier. Of course that isn't on the spec sheet many times because it is a lot easier to put a simple single # on the marketing page. The 1400 and 2400 amplifiers are totally different platforms even if both are sold by Speakerpower. Based on that I've seen the 1400 Ice based amplifier bursts quite a bit more voltage than it can sustain for long periods. The Torpedo amps are high current powerhouses that will sustain their output for many seconds into tough low impedance loads. That said they do not burst that much more than they can sustain into higher impedances. Compare the 2400-ULF maximum sweep level vs the 1400. Then compare the burst data if you want to see this visualized.


3.)Limiter circuitry can be another area of differentiation. Perhaps the 2400-ULF limiter was set a bit tighter than some other JTR subs. Often letting the limiter go might squeek another dB out of the speaker, if it can take it, but can come at the cost of harsh clipping sounds from the amp. Do you want the higher dB for the bench-racers or do you want to keep the sub much better behaved at the limit and minimize any possible bad noises, and / or damage?


4.)From what I recall the 2400-ULF I tested was the deep version with a smaller baffle area. Jeff can confirm. Baffle area does have some effect on directivity and output on axis. The picture on the site is one I took from the JTR site. We didn't take any pictures of the subs that day. I've asked Jeff for some high quality ones we can use for DB.


5.)Amp gain...Yes the 2400-ULF was tested at 2/3rds gain. I try to use full gain as much as possible. For some reason there was a hum issue that day and putting the gain down a bit helped mitigate it. Jeff and I discussed this and tested with bursts at a few frequencies to see if it made any difference in the maximum output vs full gain. It did not. We also discussed the maximum input voltage to the input stage and the input sensitivity to the amp.


6.)Vented sub design. In short there is no free lunch and everything involves tradeoffs. You will lose some overall sensitivity and efficiency by tuning 2/3rds octave lower. Driver excursion will increase when asked to reach the same output levels as the higher tuned design above the vent tuning. I mentioned this a bit in the review notes. H.I.L. is a Mutha.


7.)Temperature and barometric pressure do impact sound pressure. However it's effect is being greatly overblown here. Most of the measurement sessions I do are conducted between about 65 and 85 degrees. From recollection I'd say that some are down near 60deg maybe lower and others are above 90F. I know that 2 subs (Both of which were my designs) were tested in near 100 deg weather. I may see a variation of 1dB during calibration between a 65deg day and a 90deg day. When I unpack my rig and setup to test I let the mic and calibrator sit in the open air for quite a while to get acclimated. I never see more than about a half dB variation. When I pulled out the rig which hadn't been touched since last November it was within 0.3dB. It just doesn't vary by huge amounts within a 10deg shift like is being speculated. I checked 3 times that session and it barely moved. I usually test at night during the summer. After a few of those really hot days melting surrounds off of aluminum cones, getting sunburned and whatforth back 8 or 10 years ago, I decided it wasn't for me. If I do test during the day I place a white blanket or sheet on the speaker covering the sides, back panel and the amplifier. The front of the sub is always in shadow due to the direction it is facing. This was done in this case as per usual. This keeps the sub and the air inside from heating up more than the ambient air. If the sub was sitting unprotected in the direct sun for 4 hours with the enclosure burning hot then we might have cause for concern but that is not what happened. I'm probably going to make myself take a control sub out this winter and get some data on this. There are a few studies and papers that already deal with this subject though.


I hope that clears some of this up. Anyway the results are what they are and I stand by what I measured from that speaker on that day. All of the above are reasons that splitting speakers down to the last dB of burst output is not recommended. And that hasn't even gotten into other data sets from different people and equipment! For some reason there seems to be an expectation that this would match or even be stronger than the regular Cap 1400 everywhere across the board. IMO that was never a realistic expectation just based on it being tuned 2/3rd's of an octave lower for starters.

Last edited by Ricci; 06-01-2018 at 03:09 PM.
Ricci is offline  
post #8505 of 12958 Old 06-01-2018, 03:17 PM
AVS Forum Addicted Member
 
Marc Alexander's Avatar
 
Join Date: Aug 2001
Location: Inland Empire, CA
Posts: 13,336
Mentioned: 231 Post(s)
Tagged: 0 Thread(s)
Quoted: 5333 Post(s)
Liked: 4835
Quote:
Originally Posted by imureh View Post
@Marc Alexander , just for my education, the temperature point intrigues me. I had not heard much about it in past comparisons and I wonder how would ever any of the measurements done by Ricci would be under the same conditions? Does that not render all the comparisons at data-bass useless since they were all done under different conditions? I am sure they make a difference but doubt they are audible? Just keen to understand this issue as I think it’s negligible IMO.
There are many factors that affect measurements. Temperature, humidity, and elevation/barometric pressure. can all affect measurements. I've measured ~1dB differences measuring the same sub 14 hours apart. That's why it is not a good idea to mix data sets from different sources.

This is the best read I know of regarding the variability of CEA/CTA-2010-B measurements: https://www.soundandvision.com/conte...-baseline-bass

The ANSI/CTA-2010-B Standard (Nov. 2014) states the following:
Quote:
4.1 General Test Setup and Conditions All testing shall be conducted in an anechoic chamber or equivalent environment. During testing the DUT (device under test) shall be operated as per manufacturer’s instructions. Complete systems shall be tested intact. Testing should be conducted at an ambient temperature of 22 °C ± 5 °C (71.6 °F ± 9 °F) and a relative humidity of 30 % to 80 %. If the conditions are different, they shall be noted at the time of the test. Both of these items shall be recorded at the time of the tests. The ambient atmospheric pressure (in pascals) shall also be recorded.
HSU Research presents its data in the format most consistent with the standard. However, in my opinion data-bass has superceded ANSI/CEA/CTA. With good reason: https://data-bass.com/know-how

This may be the first time @Ricci 's data sets in comparison to each other is being questioned. I'm hoping he will comment directly. (Edit: Now that was fast!)

Last edited by Marc Alexander; 06-01-2018 at 03:37 PM.
Marc Alexander is online now  
post #8506 of 12958 Old 06-01-2018, 03:18 PM
AVS Forum Special Member
 
torii's Avatar
 
Join Date: Mar 2015
Posts: 6,866
Mentioned: 48 Post(s)
Tagged: 0 Thread(s)
Quoted: 3415 Post(s)
Liked: 1900
I bet wind skews more measurements than any of the other variables.

Power: Marantz sr7008, NAD C 275Bee x 2, Video: Oppo 103, Samsung 75un6300
Speakers: Focal aria 948, Focal cc900, Klipsch synergy KSF 10.5, Magnepan LRS
Subs: Rythmik FV25HP, Rythmik FV15HP
torii is offline  
post #8507 of 12958 Old 06-01-2018, 03:32 PM
AVS Forum Addicted Member
 
Marc Alexander's Avatar
 
Join Date: Aug 2001
Location: Inland Empire, CA
Posts: 13,336
Mentioned: 231 Post(s)
Tagged: 0 Thread(s)
Quoted: 5333 Post(s)
Liked: 4835
Quote:
Originally Posted by Ricci View Post
The 1400 and 2400 amplifiers are totally different platforms even if both are sold by Speakerpower. Based on that I've seen the 1400 Ice based amplifier bursts quite a bit more voltage than it can sustain for long periods. The Torpedo amps are high current powerhouses that will sustain their output for many seconds into tough low impedance loads. That said they do not burst that much more than they can sustain into higher impedances. Compare the 2400-ULF maximum sweep level vs the 1400. Then compare the burst data if you want to see this visualized.
Very interesting. I had not considered this.
Quote:
7.)Temperature and barometric pressure do impact sound pressure. However it's effect is being greatly overblown here. Most of the measurement sessions I do are conducted between about 65 and 85 degrees. From recollection I'd say that some are down near 60deg maybe lower and others are above 90F. I know that 2 subs (Both of which were my designs) were tested in near 100 deg weather. I may see a variation of 1dB during calibration between a 65deg day and a 90deg day. When I unpack my rig and setup to test I let the mic and calibrator sit in the open air for quite a while to get acclimated. I never see more than about a half dB variation. When I pulled out the rig which hadn't been touched since last November it was within 0.3dB. It just doesn't vary by huge amounts within a 10deg shift like is being speculated. I checked 3 times that session and it barely moved. I usually test at night during the summer. After a few of those really hot days melting surrounds off of aluminum cones, getting sunburned and whatforth back 8 or 10 years ago, I decided it wasn't for me. If I do test during the day I place a white blanket or sheet on the speaker covering the sides, back panel and the amplifier. The front of the sub is always in shadow due to the direction it is facing. This was done in this case as per usual. This keeps the sub and the air inside from heating up more than the ambient air. If the sub was sitting unprotected in the direct sun for 4 hours with the enclosure burning hot then we might have cause for concern but that is not what happened. I'm probably going to make myself take a control sub out this winter and get some data on this. There are a few studies and papers that already deal with this subject though.
This is all great info as I am still refining my test procedures to ensure consistency. I have started using a blanket in the same manner. I've decided to start using a control sub.
Quote:
I hope that clears some of this up. Anyway the results are what they are and I stand by what I measured from that speaker on that day. All of the above are reasons that splitting speakers down to the last dB of burst output is not recommended. And that hasn't even gotten into other data sets from different people and equipment!
That was incredibly helpful! Thanks!!
cannga likes this.
Marc Alexander is online now  
post #8508 of 12958 Old 06-01-2018, 03:34 PM
AVS Forum Addicted Member
 
Marc Alexander's Avatar
 
Join Date: Aug 2001
Location: Inland Empire, CA
Posts: 13,336
Mentioned: 231 Post(s)
Tagged: 0 Thread(s)
Quoted: 5333 Post(s)
Liked: 4835
Quote:
Originally Posted by torii View Post
I bet wind skews more measurements than any of the other variables.
The wind doesn't skew the measurments, it make measurement impossible.

Where I measure gets very windy (Santa Anas). Windier so far this year than I've remembered in years past.
cannga likes this.
Marc Alexander is online now  
post #8509 of 12958 Old 06-01-2018, 03:52 PM
AVS Forum Special Member
 
imureh's Avatar
 
Join Date: Mar 2009
Location: Houston, TX
Posts: 4,360
Mentioned: 201 Post(s)
Tagged: 0 Thread(s)
Quoted: 2728 Post(s)
Liked: 3297
Official JTR Speakers Subwoofer Thread

Very informative and thanks Ricci. I am also glad that even with my novice understanding the assumptions I was making about the impact of the ambient temp effect were not off.


Sent from my iPhone using Tapatalk
cannga likes this.

Subwoofers: Dual Rythmik FV18s Rev2 with Paper cone, BOSS Platform mini riser
Speakers: PSA MTM-210 L/C/R - Klipsch 250S Surrounds, PSA MT 110sr Rear Surrounds, 4 x SVS Prime Elevation for Atmos
Video: Epson PowerLite Home Cinema 6500 UB; Room: 2100 cuft sealed on suspended floor
Receiver & Players: Denon X4400H, Oppo UDP-203, Roku Ultra. Apple TV, Minidsp 2X4 HD
imureh is offline  
post #8510 of 12958 Old 06-01-2018, 04:07 PM
AVS Forum Special Member
 
chucky7's Avatar
 
Join Date: Apr 2002
Location: Rancho Cucamonga, CA
Posts: 4,545
Mentioned: 293 Post(s)
Tagged: 0 Thread(s)
Quoted: 3473 Post(s)
Liked: 4363
The following is just one example of what happens in variable tuning systems: Hsu VTF-15H:



From 25~50Hz, 1 port mode (lower port tune) averages -2dB from 25~50Hz. It's somewhat relevant as the driver, cabinet volume, amplification remain unchanged.

Of course there are much more engineering involved when Jeff lowered 2400ULF's port tune to 10Hz.
cannga and Marc Alexander like this.

Speakers: L/C/R: JTR Noesis 212HT. Surrounds: Jamo C103, KEF Q100, Polk Audio RTiA3.
Subwoofer: JTR Captivator 4000ULF.
AVR: Denon AVR-X4400H. TV: Samsung UN75NU8000FXZA.

FS: Jamo C103, KEF Q100 and Polk RTiA3

Last edited by chucky7; 06-01-2018 at 06:39 PM.
chucky7 is offline  
post #8511 of 12958 Old 06-01-2018, 04:29 PM
Member
 
Lorderl's Avatar
 
Join Date: Jun 2009
Location: New Haven, CT
Posts: 172
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 102 Post(s)
Liked: 50
Quote:
Originally Posted by chucky7 View Post
Of course there are much more engineering in what Jeff did when he lowered 2400ULF's port tune to 10Hz.
Maybe should have engineered a Cap2700-3000ULF Above 20hz the Cap2400ULF is amp limited after all.
cannga likes this.

Display: Samsung LN55B650
AVR: Denon 2809ci
Players: OPPO BDP-83 || Streaming: Amazon Fire TV || Kindle Fire HD8
Speakers: Paradigm Studio 20v3 || CC-570v3 || ADP-470v3
Sub: JTR Captivator 2400ULF-10hz

Last edited by Lorderl; 06-01-2018 at 04:52 PM.
Lorderl is offline  
post #8512 of 12958 Old 06-01-2018, 05:03 PM
AVS Forum Special Member
 
chucky7's Avatar
 
Join Date: Apr 2002
Location: Rancho Cucamonga, CA
Posts: 4,545
Mentioned: 293 Post(s)
Tagged: 0 Thread(s)
Quoted: 3473 Post(s)
Liked: 4363
Quote:
Originally Posted by Lorderl View Post
Maybe should have engineered a Cap2700-3000ULF Above 20hz the Cap2400ULF is amp limited after all.
The next level up from the SpeakerPower 2400W plate amp is the 4000W amp, so unless Jeff starts sourcing amps from other vendors...

However, I am sure many wouldn't mind paying the difference in price to get a couple more dB up top. This is of course assuming that the beefy driver can utilize 4000W.
cannga, SuperFist and Lorderl like this.

Speakers: L/C/R: JTR Noesis 212HT. Surrounds: Jamo C103, KEF Q100, Polk Audio RTiA3.
Subwoofer: JTR Captivator 4000ULF.
AVR: Denon AVR-X4400H. TV: Samsung UN75NU8000FXZA.

FS: Jamo C103, KEF Q100 and Polk RTiA3

Last edited by chucky7; 06-01-2018 at 06:35 PM.
chucky7 is offline  
post #8513 of 12958 Old 06-01-2018, 07:09 PM - Thread Starter
AVS Forum Special Member
 
cannga's Avatar
 
Join Date: Feb 2001
Location: Palos Verdes - Lakers Land
Posts: 3,372
Mentioned: 72 Post(s)
Tagged: 0 Thread(s)
Quoted: 1869 Post(s)
Liked: 1825
Goodness I love the discussion.
Thanks everyone for participating.

Very glad we finally got @Ricci to have a guest appearance in this thread. His work provides crucial background for nearly ALL the spirited arguments here. :-)

I know if we keep "fighting" and "arguing" Josh will finally have to join in. Mission accomplished.

Regards, Can
My System & Theta Casablanca Mini-Review (CB IVa setup help HERE) Uncontrolled passion for music, and sound.
Interesting Audio Diagrams :-) & High-End Speaker Reviews
JTR Subwoofer Thread I don't always listen to subwoofers, but when I do, it's JTR :-).

Last edited by cannga; 06-01-2018 at 07:25 PM.
cannga is offline  
post #8514 of 12958 Old 06-01-2018, 07:25 PM
AVS Forum Addicted Member
 
MKtheater's Avatar
 
Join Date: Jul 2006
Location: New Hartford, NY
Posts: 18,483
Mentioned: 135 Post(s)
Tagged: 0 Thread(s)
Quoted: 2427 Post(s)
Liked: 2407
Guys, when you start tuning really low you will lose mid bass. Same goes for giant sealed boxes or IB compared to small sealed cab. This is fine because like the said before, you will not be lacking mid bass with the 2400ulf but gain lots of extension. It comes down to your room and setup. These 18s all deliver gobs of midbass, in a room you gain spl from having many boundaries around the sub as well. I sit 12 feet away and lose 6 dB from the sub to the listening position. People gain 3 dB per boundary I believe. This is why subs can play much louder in room. If one watches at reference and has 10 dB of increased LFE then 125 dB would only be needed if the source was recorded at 0 dBFS which never happens, unless I missed that graph somewhere. So if recorded at -5 dB then 120 dB is needed and the 2400ULF can reach that outside. All this 3 dB more midbass is nonsense. It takes more x-max, amp, and a more robust driver to dig deep and why costs more. The pro audio world has been reaching high spl mid bass for a very long time. The low end is the hard part.
cannga, chucky7, SuperFist and 1 others like this.

Nothing right now
MKtheater is offline  
post #8515 of 12958 Old 06-01-2018, 07:29 PM - Thread Starter
AVS Forum Special Member
 
cannga's Avatar
 
Join Date: Feb 2001
Location: Palos Verdes - Lakers Land
Posts: 3,372
Mentioned: 72 Post(s)
Tagged: 0 Thread(s)
Quoted: 1869 Post(s)
Liked: 1825
Quote:
Originally Posted by chucky7 View Post


Thanks buddy. Will post this on first page as usual.

BTW regarding on going discussion, I agreed of course that nothing comes free, a low tune will affect upper bass output (mthomas47 and I first discussed this a few pages back). Having said that, IMHO because the 2400 starts out with such powerful driver and amp, even after the "sacrifice," it still is a tremendously potent subwoof in the upper range. As owner of 1400 which seems to be part of the point of contention here, I would still vote for new 2400 because of the eye popping 10 Hz output.

IMHO, deep bass is expensive bass; it's what I, and I believe most of us bass-heads, chase. It is what makes this hobby so fun and exciting. So given the chance I'd go for it hook, line, and sinker. And please don't make me quote Fletcher Munson curve again .

Regards, Can
My System & Theta Casablanca Mini-Review (CB IVa setup help HERE) Uncontrolled passion for music, and sound.
Interesting Audio Diagrams :-) & High-End Speaker Reviews
JTR Subwoofer Thread I don't always listen to subwoofers, but when I do, it's JTR :-).

Last edited by cannga; 06-01-2018 at 09:12 PM.
cannga is offline  
post #8516 of 12958 Old 06-01-2018, 08:48 PM
Member
 
Join Date: May 2017
Posts: 130
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 177 Post(s)
Liked: 20
So the ones who just ordered at the end of May receive the older version or the newer 2400. Any word from Jeff on this? I have not been able to get in touch with him so not sure what the latest update is. Am still waiting for confirmation on the finish upgrade too.

Last edited by mir3acles; 06-01-2018 at 08:52 PM.
mir3acles is offline  
post #8517 of 12958 Old 06-01-2018, 08:56 PM
AVS Forum Addicted Member
 
Marc Alexander's Avatar
 
Join Date: Aug 2001
Location: Inland Empire, CA
Posts: 13,336
Mentioned: 231 Post(s)
Tagged: 0 Thread(s)
Quoted: 5333 Post(s)
Liked: 4835
Quote:
Originally Posted by mir3acles View Post
So the ones who just ordered at the end of May receive the older version or the newer 2400. Any word from Jeff on this? I have not been able to get in touch with him so not sure whats going on with the order.
I believe you will receive the 10Hz from now on. The 14Hz will only be by special request.

There is a queue and probably an influx of orders prior to June 1. I see the website hasn't been updated yet.

Which version would you prefer if you don't mind me asking.
mir3acles likes this.
Marc Alexander is online now  
post #8518 of 12958 Old 06-01-2018, 09:03 PM
Member
 
Join Date: May 2017
Posts: 130
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 177 Post(s)
Liked: 20
Quote:
Originally Posted by Marc Alexander View Post
I believe you will receive the 10Hz from now on. The 14Hz will only be by special request.

There is a queue and probably an influx of orders prior to June 1. I see the website hasn't been updated yet.

Which version would you prefer if you don't mind me asking.
I am not sure myself. I don't understand a lot of the stats yet, so hard for me to say. (I don't know how much the deep extension would matter to take that out from the mid-range in the real world) I personally would like to hear both to decide which is better but probably this will not be possible. Whatever sounds good to the ear is what matters more I guess. I am sure Jeff would have done more of an upgrade than a downgrade, In your opinion which one would you have preferred (sorry for throwing the questions back) since you have more experience and knowledge about it than me for sure.

Last edited by mir3acles; 06-01-2018 at 09:09 PM.
mir3acles is offline  
post #8519 of 12958 Old 06-01-2018, 09:12 PM
AVS Forum Addicted Member
 
Marc Alexander's Avatar
 
Join Date: Aug 2001
Location: Inland Empire, CA
Posts: 13,336
Mentioned: 231 Post(s)
Tagged: 0 Thread(s)
Quoted: 5333 Post(s)
Liked: 4835
Quote:
Originally Posted by mir3acles View Post
I am not sure myself. I don't understand a lot of the stats yet, so hard for me to say. (I don't know how much the deep extension would matter to take that out from the mid-range in the real world) I personally would like to hear both to decide which is better but probably this will not be possible. Whatever sounds good to the ear is what matters more I guess. In your opinion which one would you have preferred (sorry for throwing the questions back)
What are the details of your setup & room?

I own the 14Hz 2400ULF. Tomorrow I will test with both ports open vs one port plugged. I don't have the DSP settings [yet] to take full advantage of the 10Hz tune but I should get an accurate picture of the trade-off in the upper bass.

For my downstairs I prefer the 14Hz tune. It is open concept with no room gain below 16Hz. For my upstairs (smaller, sealed room) I would choose the 10Hz.
Marc Alexander is online now  
post #8520 of 12958 Old 06-01-2018, 09:27 PM
AVS Forum Addicted Member
 
Marc Alexander's Avatar
 
Join Date: Aug 2001
Location: Inland Empire, CA
Posts: 13,336
Mentioned: 231 Post(s)
Tagged: 0 Thread(s)
Quoted: 5333 Post(s)
Liked: 4835
Quote:
Originally Posted by chucky7 View Post
The following is just one example of what happens in variable tuning systems: Hsu VTF-15H:



From 25~50Hz, 1 port mode (lower port tune) averages -2dB from 25~50Hz. It's somewhat relevant as the driver, cabinet volume, amplification remain unchanged.

Of course there are much more engineering involved when Jeff lowered 2400ULF's port tune to 10Hz.
Thanks @chucky7 this is a good world example. However, my measurements of the Monolith and the Rythmik subs' VT modes don't show an upper-bass drop-off and neither does data-bass.

My testing tomorrow should be telling. I only expecting the differences in output (over fractions of a dB) to occur around the tuning frequencies. Let me know if you are available to bring the 1400 by.

Last edited by Marc Alexander; 06-01-2018 at 09:39 PM.
Marc Alexander is online now  
Sponsored Links
Advertisement
 
Reply Subwoofers, Bass, and Transducers

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page


Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off