Subwoofer comparisons and impressions - Page 49 - AVS Forum | Home Theater Discussions And Reviews
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post #1441 of 1930 Old 04-20-2019, 10:26 AM
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Originally Posted by Mark Seaton View Post
Ascendo even has their crazy/cool 50" subwoofer the SMSG 50. Yes, I'm a little jealous, and yes, even that large cone can produce very clean bass.
@Mark Seaton Ever since you brought this up, I can't stop thinking about that monster lol

How on earth can they drive that with only a 6000W amplifier?

https://www.aia-cinema.com/active-speakers/smsg50.html
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post #1442 of 1930 Old 04-20-2019, 10:35 AM
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Originally Posted by chucky7 View Post
You probably didn't. However, like all subs present that day, it had a fair chance to shine: https://www.avsforum.com/forum/61-ar...l#post56886984

Maybe you were running around playing music chair?
I must have excused myself to the kitchen/food.

Regardless, this thread is about comparison of subs in differing rooms. Not dissing one to uplift another.
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post #1443 of 1930 Old 04-20-2019, 10:47 AM - Thread Starter
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Originally Posted by Marc Alexander View Post
I must have excused myself to the kitchen/food.

Regardless, this thread is about comparison of subs in differing rooms. Not dissing one to uplift another.
I have always said as Marc pointed out that the V1801 sounded very good in my room and I never experienced any port noise. I honestly did not know what I was missing till I heard Todd's 2400s and wanted to feel that low bass weight
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post #1444 of 1930 Old 04-22-2019, 10:11 AM
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Quote:
Originally Posted by Todeseng3l View Post
@Mark Seaton Ever since you brought this up, I can't stop thinking about that monster lol

How on earth can they drive that with only a 6000W amplifier?

https://www.aia-cinema.com/active-speakers/smsg50.html
Read my previous post about the line source and combining or breaking up drivers. It's always a function of the motor, mass, suspension, cone size, and box. That last variable of box size is where your question really hangs on. In a large enough box, we could probably get +/-1 inch with well under 1000W. Box size always sets a limit on the maximum efficiency at some low frequency. Resonant and horn systems can be higher than a sealed box for a limited bandwidth. With a sealed box, a given box volume largely sets a 12dB/octave threshold for maximum sensitivity for 1W nominal input, meaning you can max out 12dB greater at 20Hz than 10Hz, and 40Hz than 20Hz. You can fudge the line 1-3dB with undamped bumps or getting loose with impedance specs, but if you instead hold a constant voice coil resistance, you clearly see what the practical limits are.

In short, unless the woofer is not well optimized for the enclosure, a significantly larger box will take LESS power to reach the same SPL. If you figured out the effective area of the 50" woofer and divided it by the effective area of an 18" woofer, and divide the box size by that ratio, you can see how large a box you have per 18" woofer, which gives you a better frame of reference as to how compact or large the box might be.

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post #1445 of 1930 Old 04-22-2019, 02:28 PM
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Originally Posted by chucky7 View Post
So we have confirmed info about PSA's new offerings:

1A. Current 18" drivers, 46" H x 20" W x 27" D, 1920w, 6" flared bottom firing port, front firing drivers.
$2,199 pre-order, $2,599 regular.

1B. New Neo 18" drivers, 46" H x 20" W x 27" D, 1920w, 6" flared bottom firing port, front firing drivers.
$2,599 pre-order, $2,999 regular - regular neo driver.
$2,999 pre-order, $3,499 regular - more robust neo driver.

Only one of the 1b will be available. So far, the port tune is not confirmed by PSA.

2a. Big sub.
So what are the specs of these new offerings? How low is the tune and their +-3db?
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post #1446 of 1930 Old 04-22-2019, 02:33 PM
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13.5 Hz


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post #1447 of 1930 Old 04-22-2019, 02:41 PM
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Quote:
Originally Posted by tvuong View Post
So what are the specs of these new offerings? How low is the tune and their +-3db?

Here is Tom's quote from the PSA subwoofer thread and their Facebook page.


Quote:


Hi all,
Update on the new "low tune" subs everyone has been asking us for since 2017..
I understand there will be disappointment with the lack of a website update specific to the new designs but there's just no time for that at the moment. I have well over 10,000 products in the field now. Combine that with a fairly large back-list. Those customers will always demand top priority over marketing for new orders.
You can order over the website or call me to get in on the pre-order discounts. Some may be more comfortable waiting a bit for actual production quality pictures and the website update/page---that is completely understandable. I can't promise when any of that will happen but I'll do my very best to try to get it all done as quickly as possible---hopefully by the end of the week. The final production/photo quality cabinet has been delayed about a week and won't be here for another 2-4 business days anyway. Everything is still on track for shipments to begin in May. And hopefully closer to mid May than late May. I remember we sold a ton(literally a couple tons worth) of the t18 before we even had a web page for it so who knows..
I'm going to get a maximum of 24 cabinets on the first production run. Once those are spoken for the pre order ends. That may be 2 days or 2 weeks. It's difficult to guess.
Here are the main details.
* The amplifier is our 1920w platform. I can make the argument it is putting out more power but I'm really not worried about trying to market these. At the moment interest is way beyond anything I could have hoped for anyway.
* The cabinet is the same for all three options. Two front firing 18s, single down firing 6 inch flared port, full face grill.
20x26x48( WxDxH ).
Tune is 13.5hz +/- 0.5hz.
FR is (+/-3) 15hz-150hz anechoic. 7-10hz pressurization in all but the largest rooms.
Cea-2010 will be finalized as weather/time allows. I will say along with the dramatic increase in 10-20hz performance we haven't sacrificed much mid and upper bass impact. There's *some* trade off of course, that is just physics. But even if you put the base version next to a V3611 you would be hard pressed to notice this. This is due to the fact that the V3611 was such a mid/upper bass entity that even if you lose a couple/few dB there it's hard to find source material and listening levels where it's jumps out at you.
The woofer options are as follows--- There are three.
TV36 = standard 18 inch woofers we've been using with outstanding results for quite a while now. Full details on available on any current 18 inch based product page on the website.
$2199 pre-order. $2599 is the estimated regular pricing.
---------------------------------------------------------------------------
TV36neo = A high end Neo woofer from Italy(B&C). Exceptional distortion control, exceptionally strong motor, build quality and power handling/thermal limits are far beyond anything we've offered to date.
$2599 pre-order. $2999 is the estimated regular pricing.
https://www.bcspeakers.com/en/produc...-0/4/18ds115-4
This one sound a bit different than the base version. Better overall. Similar <25hz to the base version but this driver is such a beast in efficiency it goes toe-toe with the V3611 in 40-100hz without breaking a sweat. So my one line description would be.
~ The TV36neo give you all of the violent mid and upper bass of the V3611 while pressurizing the room down to 10hz and below.
------------------------------------------------------------------------------
TV36ipal + Ipal 18" woofer. Arguably the highest quality 18 inch woofer available anywhere, at any price.
$2999 pre-order. $3599 is the estimated regular pricing.
https://www.bcspeakers.com/en/produc.../18-0/2/18ipal
The cleanest, most linear, strongest motor woofer I have ever used/measured...and there's been nothing even remotely close. The sound quality reflects this as well. I'm not going to wax poetically, that's always been difficult. But our proprietary ICE design match with IPAL technology is truly something special.


Source


https://www.facebook.com/powersoundaudio/

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post #1448 of 1930 Old 04-22-2019, 02:42 PM
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^^ Thanks.
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post #1449 of 1930 Old 04-22-2019, 02:43 PM
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Originally Posted by tvuong View Post
^^ Thanks.

No prob. The thread is moving a bit fast so its easier to pull from the facebook post.
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post #1450 of 1930 Old 04-22-2019, 07:55 PM
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Quote:
Originally Posted by oneeyeblind View Post
Here is Tom's quote from the PSA subwoofer thread

Tune is 13.5hz +/- 0.5hz.
FR is (+/-3) 15hz-150hz anechoic. 7-10hz pressurization in all but the largest rooms.

Based on the v3611 spec below, the 3 new psa lower tuned subs are spec’ed at 1hz lower than the current v3611. I did not know the 1hz lower at 15hz +-3db anechoic can translate to reach 7-10hz in room versus 11-14hz of the v3611? . Does anyone know the port tune of the v3611?

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post #1451 of 1930 Old 04-22-2019, 08:01 PM - Thread Starter
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Subwoofer comparisons and impressions

Quote:
Originally Posted by tvuong View Post
Based on the v3611 spec below, the 3 new psa lower tuned subs are spec’ed at 1hz lower than the current v3611. I did not know the 1hz lower at 15hz +-3db anechoic can translate to reach 7-10hz in room versus 11-14hz of the v3611? . Does anyone know the port tune of the v3611?




I think it was 17-18hz? Not sure may be @Hopinater or @David Charles know? Not sure if @Marc Alexander had measured this one or not.

Edit: actually I see Marc just recently asked Tom about the port tune of the v3611 but don’t think he got an answer. So I don’t he would know.


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Subwoofers: Dual Rythmik FV18s Rev2 with Paper cone, BOSS Platform mini riser, 2 BK LFE
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

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post #1452 of 1930 Old 04-22-2019, 08:58 PM
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If the V1811 is tuned to low 20s Hz...

then the V3601 should be similar...

Speakers: L/C/R: JTR Noesis 212HT. Surrounds: Jamo C103, KEF Q100, Polk Audio RTiA3.
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Last edited by chucky7; 04-22-2019 at 09:04 PM.
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post #1453 of 1930 Old 04-23-2019, 05:11 AM - Thread Starter
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Originally Posted by chucky7 View Post
Yes, I read it right.

Your post above has nothing to do with what Basshead81 asked. Basshead81 didn't ask about usable output. He asked about the relationship between port tune and the FR + variation, or F3. Since PSA hasn't had any sub tested in years, I used a DB tested ported Rythmik as an example to illustrate that. It got a little complicated because the FV25HP has a rumble filter.

I could have used a DB tested ported JTR but I didn't want members to think I am advertising a brand that I own.
I am moving the conversation here since the question that Basshead asked was asked by Tony as well let @enricoclaudio chime in on your statement

Subwoofers: Dual Rythmik FV18s Rev2 with Paper cone, BOSS Platform mini riser, 2 BK LFE
Speakers: PSA MTM-210 L/C/R - Klipsch 250S Surrounds, PSA MT 110sr Rear Surrounds, 4 x SVS Prime Elevation for Atmos
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post #1454 of 1930 Old 04-23-2019, 06:01 AM
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Quote:
Originally Posted by chucky7 View Post

If the V1811 is tuned to low 20s Hz...

then the V3601 should be similar...
How did you come to assume they are 20s Hz port tune? Based on these sketches (since you posted)? Or based on measurements you have seen?

Last edited by tvuong; 04-23-2019 at 07:04 AM.
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post #1455 of 1930 Old 04-23-2019, 06:06 AM
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I am moving the conversation here since the question that Basshead asked was asked by Tony as well let @enricoclaudio chime in on your statement
I guess he saw what I pointed out here is valid but decided to ask in the owner thread instead.
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post #1456 of 1930 Old 04-23-2019, 07:21 AM
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Quote:
Originally Posted by imureh View Post
I think it was 17-18hz? Not sure may be @Hopinater or @David Charles know? Not sure if @Marc Alexander had measured this one or not.

Edit: actually I see Marc just recently asked Tom about the port tune of the v3611 but don’t think he got an answer. So I don’t he would know.


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Im pretty confident that the v3611 is tuned to 19 or 20 hz. The new subs will use a straight, long port. The v3611 port wasnt very long compared to what the new sub has. I used the box port calculator that Tom linked and indeed he should be able to have a 13.5 hz tune easily. To get a 13.5 hz tuning, the port would need to be 29 inches long which is easy, considering the sub is 48 inches tall. The v3611 port tune could have been lower given the size of the cabinet.. but I just think the end goal was different with that one so maybe the design was different.

Last edited by David Charles; 04-23-2019 at 07:45 AM.
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post #1457 of 1930 Old 04-23-2019, 07:50 AM
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If you guys ever model the JTR subs the port velocity is quite high, is this the port wind everbody talks about? I made some subs with higher velocity like that and one really can't hear anything unless at the limits but TR goes up dramatically.

Building the room, speakers, and subs.
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post #1458 of 1930 Old 04-23-2019, 08:54 AM
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Hey guys, in regards to the frequency response quoted versus the port tuning there are a number of factors to consider.
Port tuning alone is not an indicator of overall frequency response shape or extension.
It is possible to make a bass reflex with a voltage sensitivity that is flat to an 18Hz tuning and have another that is 12dB down. It depends on many factors including the size of the system, driver used, etc.
After those considerations comes signal shaping. Almost every modern active sub uses some type of electronic signal shaping to modify the response shape. It can and is used to turn the raw or native (constant voltage) response into whatever the designer or end user desires it to be.
That is yet another consideration. Every designer has their own preferences and targets for a product. Some may prefer a ruler flat anechoic response to start with another may prefer to target a shallow roll off that will hopefully turn into a flat low end extension in a variety of rooms.


The short version is that it is likely that none of the subs tuned below 20Hz on the market have an unequalized response that is flat down to the tuning.
With todays signal processing it is possible to force the response to be flat down to the port tuning with a few mouse clicks. (At least until headroom limitations come into play)
If the sub isn't flat down to the tuning frequency it's likely that the designer intended it to behave that way.
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post #1459 of 1930 Old 04-23-2019, 08:55 AM
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Quote:
Originally Posted by tvuong View Post
I guess he saw what I pointed out here is valid but decided to ask in the owner thread instead.
No actually I didn't see what you posted here and I am not sure what you said is valid. What has been determined so far is that the -3db point is below the port tune on the V3611 and the -3db point is above the port tune on the TV36. That can only mean the TV36 has a shallower roll off compared to the V3611. Chucky posted some info on the FV25 that shows the same behavior.. the -3db point is actually 16hz, but has a 12hz tune...so that shows the -3db point doesn't define the subs extension capability.


Edit*


Ricci posted while I was typing this. He obviously explained it better then I did. With DSP the response can be shaped however the OEM choses...so using the old -3db point to determine a subs extension capability is old mythology in 2019...especially since OEM's no longer need to use set 24db or 48db per octave filters around the tuning point with todays amplifier technology.
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post #1460 of 1930 Old 04-23-2019, 09:02 AM
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Originally Posted by basshead81 View Post
the -3db point doesn't define the subs extension capability.

Correct.
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post #1461 of 1930 Old 04-23-2019, 09:10 AM
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^^^

This subject of port tune has come up a lot on various threads, and I think it's important to reiterate a common theme from subwoofer designers. (Josh just answered this question better than I am doing it, but I still want to make some points.)

The port tune is only one aspect of determining a subwoofer's low-frequency output. I have, in the past, tried to discern port tunes of some subwoofers by looking at quasi-anechoic (outdoor, ground plane) graphs of their frequency responses. I think it is very hard to tell even from those graphs, because the way that DSP is applied is such a major factor in determining the low-frequency limits of the sub.

For instance, with subs like the JTR Cap 2400ULF, or the SVS PB16 Ultra, some mid-bass SPL is deliberately sacrificed in order to push more amplifier power into the <35Hz frequencies. In the current 18" PSA subwoofers, the exact reverse is true. The subwoofers are rolled-off earlier, and to a greater extent, in order to maximize the mid-bass output. Some of the difference is related to the natural characteristics of the woofers chosen, but a lot of it is due to DSP.

It is easy to look at a graph of the V3611 and see how early the sub begins to roll-off, and how much it continues to roll-off down to 20Hz and below. I honestly can't look at that graph and say where the port tune is, because the DSP applied, and where the high-pass filter kicks-in, are the determining factors in the frequency response, rather than the tuning point. If you look at the native response of the V3611, you will see what I mean:

https://www.powersoundaudio.com/products/V3611

I think that it will be interesting to see how PSA adapts the DSP on its new subs over time. For instance, Jeff changed the port tune and corresponding DSP on the Cap 2400ULF from 14Hz to 10Hz, and he changed the recent Cap 118HT from 20Hz to 18Hz. I wouldn't necessarily expect the native port tune of the new PSA subs to change, but I think that Tom could choose to distribute the output differently, depending on the drivers implemented.

I'm not saying that he will make that choice, but I believe that he could. For instance, if the Neo driver or the IPAL driver has much more mid-bass capability than his current drivers, then he could choose to divert more amplifier power to the lowest frequencies for subwoofers made using those drivers. I think it's impossible for a designer to think of everything at once, but this is certainly something that we might see as the new subwoofers get out into the wild--the possibility that the different drivers end-up with slightly different low-frequency capabilities.

Regards,
Mike
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post #1462 of 1930 Old 04-23-2019, 11:46 AM
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Quote:
Originally Posted by MKtheater View Post
If you guys ever model the JTR subs the port velocity is quite high, is this the port wind everbody talks about? I made some subs with higher velocity like that and one really can't hear anything unless at the limits but TR goes up dramatically.
I have not modeled the JTR subs.

My experience is that the Cap 1400 has higher port wind than the Cap 118HT, level matched and playing the same content.

From pure physics point of view, the 33mm X-Max driver (in the Cap 1400) should be more capable of producing higher port wind than the 19mm X-Max driver (in the Cap 118HT) when all else being equal.

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post #1463 of 1930 Old 04-23-2019, 12:21 PM
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It probably has to do more with the size of the port and resulting port velocity. A higher tuned sub can get away with a bigger and shorter port which results in a lower port velocity. There are many different factors and of course with more excursion and power it pushes more spl through the port. 10hz 18 inch subs need to be massive to have very low port velocity and a higher resonance. JTR subs a tiny for 10hz subs and while there is boost to get flat. That also means the port velocity would be higher which can cause more port wind(I am guessing) but still not enough to chuff until maxed. Unless somebody has a huge room with just one sub it probably is never pushed.

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post #1464 of 1930 Old 04-23-2019, 01:21 PM
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Originally Posted by basshead81 View Post
No actually I didn't see what you posted here and I am not sure what you said is valid.
What I said in the boded part below. How can a 15hz +-3db anechoic spec translate to reach 7-10hz in room versus 11-14hz in room of the v3611 with a 16Hz +-3db anechoic spec? Is that very confusing from being 15hz versus 16Hz anechoic, don't you think? Beside, you know a port sub rolls off heavily at port tune, I like to see proof of a 15hz (-6db) or a 13.5Hz tuned sub that can still go that low (7Hz) in room other than a closet sized room.

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Originally Posted by tvuong View Post
Based on the v3611 spec below, the 3 new psa lower tuned subs are spec’ed at 1hz lower than the current v3611. I did not know the 1hz lower at 15hz +-3db anechoic can translate to reach 7-10hz in room versus 11-14hz of the v3611? . Does anyone know the port tune of the v3611?

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Originally Posted by basshead81 View Post
What has been determined so far is that the -3db point is below the port tune on the V3611 and the -3db point is above the port tune on the TV36. That can only mean the TV36 has a shallower roll off compared to the V3611.
First, -3db is not the same as +/-3db spec. +/-3db means -6db. Who determines the boded part above as it is so vague and misleading.
The best way to clear these confusions from PSA specs is to send a sub to Ricci.

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Originally Posted by basshead81 View Post
Chucky posted some info on the FV25 that shows the same behavior.. the -3db point is actually 16hz, but has a 12hz tune...so that shows the -3db point doesn't define the subs extension capability.
What Chucky posted in that screenshot from data-bass is what Josh describes the effect of the Rythmik frequency and damping switches, NOT its frequency response nor port tune frequency.


Last edited by tvuong; 04-24-2019 at 10:14 AM.
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post #1465 of 1930 Old 04-23-2019, 01:24 PM
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Originally Posted by basshead81 View Post
Ricci posted while I was typing this. He obviously explained it better then I did. With DSP the response can be shaped however the OEM choses...so using the old -3db point to determine a subs extension capability is old mythology in 2019...especially since OEM's no longer need to use set 24db or 48db per octave filters around the tuning point with todays amplifier technology.
I'll echo Ricci's comments, with some hope of simplifying a little further. While I would probably choose different ways to more clearly express the specification (or a picture says 1000 words here), you can pick what ever +/- tolerance you feel is relevant, but it's not like a speaker suddenly turns off when you get to a +/- 4dB window. The deeper extending sealed subs all take advantage of the naturally shallower roll of and lack of a hard low frequency operational limit. With the right shape between 10-20Hz, or say 15-30Hz you will often see a very complimentary match to the low frequency gain function of most rooms that have a least 3 solid walls and a less than ~20' ceiling. Our SubMersive and F18 has demonstrated extension to 7-12Hz in most rooms with an anechoic response that fits +/-3dB from 18-19Hz to the above 120Hz. Of course I could spec the same box as being say +/-1dB from 30-100Hz AND +1/-10dB from ~13-250 Hz. It's just a matter of picking your window in a way that's applicable to the use. Similarly you will often see amplifier specifications +/- some fraction of a dB along with a much wider +/-3dB spec. If you really want to see what's going on, perform sweeps and increasing level into the limits, and for ported subs also get a nearfield measurement with the microphone ~0.5" from the woofer cone. Tom's already made a few references to the Data-Bass measurements of the X-21 vs what he saw possible in his product. You can see there what a big pro driver in a low tuned cabinet does with and without EQ. The response curve shown with the Behringer amp with 2 ports open is already a little flatter than I would set as neutral on such a product, and looking at the space between the raw and EQ'd response should give you an idea of what is going on with their new lower tuned subs. For a comparative reference, the response I optimized for the Terraform D18 subwoofer I did a limited run of almost 5 years ago were tuned to 10.5-11Hz and were -10-12dB at 10Hz vs the flat passband of 35-100Hz. This still gives a nicely rising VLF response in many rooms, regardless of the ground plane +/-3dB window.

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post #1466 of 1930 Old 04-23-2019, 03:47 PM
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Originally Posted by oneeyeblind View Post
Here is Tom's quote from the PSA subwoofer thread and their Facebook page.

Source https://www.facebook.com/powersoundaudio/
These are exciting times for PSA owners. Having such a attractive trade-in program really benefits the consumers. I was pleasantly surprised to learn that all 3 drivers would be offered. The pre-order pricing is so attractive that I even considered ordering a TV36ipal myself.

In the PSA thread I read of some folks inquiring about single driver versions, rather than dual 18s. I immediately thought about the X21s Seaton Sound offers. The 21" versions of the same B&C drivers are offered. Also, both passive (w/DSP recommendations) and active versions are options. https://seatonsound.net/product/x21subwoofer/

I suspect that the X21s and TV36Xs will measure similarly (X21 ipal ds115-4 was already tested by @Ricci ). I'm foaming at the mouth to directly compare the two with the same driver model because I suspect there will be a difference in tactile response as the X21 has front facing-ports and variable tune while the TV36X have the single down-facing port.

I'm sure both have ample TR. I just see it as a good opportunity for learning more about TR in regards to port & driver orientations.

I read that PSA may be offering more premium wood veneers in the future (S1510 & S3010 only at the moment). Previously I had mentioned that Seaton, JTR, DSS and Funk offer premium veneers (not just wood) on all of their products. @Rythmik; recently reminded me that Jim Salk can build any Rythmik sub with premium veneer.
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post #1467 of 1930 Old 04-23-2019, 04:02 PM
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I havent heard many of the latest subs...do people in the know think they all sound the same or whats the dealio? is it all about TR? what type of spl's are people trying to compare subs at? I can do 120's db and think I have very weak bass...even my old man thought my bass was weak when demo'ing his classical stuff. 120 db's and weak bass...who woulda thunk?


edit to add my space is 20k cuft open layout....so not a knock on subs per se.

Power: Marantz sr7008, NAD C 275Bee x 2, Video: Oppo 103, Samsung 75un6300 LG oled c9 77
Speakers: Focal aria 948, Focal cc900, Klipsch synergy KSF 10.5, Magnepan LRS, Audioengine A2+
Subs: Rythmik FV25HP, Rythmik FV15HP, Velodyne HGS 12, Velodyne VA1512

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post #1468 of 1930 Old 04-23-2019, 07:26 PM
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Josh and Mark covered it well. You may have missed @basshead81 's follow-up.
Quote:
Originally Posted by basshead81 View Post
What was being questioned is why the TV36 -3db point (15hz) and the V3611 -3db 16hz if the TV36 extends deeper?



The Answer:



With today's DSP amplifier technology, -3db doesn't reveal a ported subs extension capability or tuning point. Many use to assume -3db was the area around the ported subs tune. In the past with analog amps that was probably a safe bet, but with DSP things can be manipulated more. I didn't realize this until I did some research this morning.



So even though both the TV36 and V36 have a similar -3db, the extension capabilities are completely different. Being the TV36 -3db point is above it's port tune tells me there is much less DSP applied down low to get the -3point down into the mid teens. However with the V3611 having a 18-19hz tune but a -3db of 16hz tells me it's requires much more DSP down low to get a flat response.



So in the end we can't base anything on -3db alone. The TV36 is going to play lower with much less effort because there is less DSP applied and it's hitting those frequencies on it's own.



I bring this up to try and paint a example of the difference in capability between the 2. If I am spending 2599.00 on a sub this is the technical stuff I like to know. Some just see a new toy and throw caution to the wind and that is OK but not how I roll.



Hopefully this helps others understand that again, even though both subs -3db are within 1hz, that doesn't mean they will have the same capabilities below 20hz.



I probably should of waited to post my initial question on this topic from a Computer so it was more clear. I am not a Mike Thomas on a keyboard by any means.
PSA, JTR, and Seaton all have their own DSP tuning techniques and their own sound signatures.

Nathan Funk has and will build ported subs, but he will strongly recommend his sealed offerings first.

@Mark Seaton hasn't mentioned it lately, but he once mentioned a killer idea for a next-gen Teranova. Mark, does the X21 negate the development of a new Teranova design?

TERRAFORM!
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Last edited by Marc Alexander; 04-23-2019 at 08:51 PM.
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post #1469 of 1930 Old 04-23-2019, 07:32 PM
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Do you mean Terraform?

Building the room, speakers, and subs.
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post #1470 of 1930 Old 04-23-2019, 08:31 PM
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Quote:
Originally Posted by Marc Alexander View Post
(X21 ipal was already tested by @Ricci )
21Ipal's were tested but not in Mark's X21. That was the 21ds115-4. I've got a few of those as well.
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