AudioCircle
Audio/Video Gear and Systems => Owner's Circles => VMPS Speakers => Topic started by: esprits4s on 19 Mar 2016, 01:28 am
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Hi,
Anyone have the specifications for the Super Tower /R SE's that they could share. I've searched high and low online and haven't been able to find them. Info on the original /R's is available, but not the later SE's.
Thanks!
-Gary
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From a 1999 Stereo Review Buyer's Guide:
Super Tower/R Special Edition 4-Way Speaker
Two 15" and one 10" woven-carbon woofers, two 5" dynaribbon-planar midranges, two Focal 1" dome tweeters, and one 2" ribbon super- tweeter. Power handling 350W; FR 20-40khz; sens 90dB; imp 4 ohms; 100 lb
$3,400/pr
$2,800/pr kit
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Thank you!!!
I love this forum:)
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BTW, were the dimensions listed in that review?
Thanks!
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I checked several Buyer's Guides, no dimentions. :(
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Hmm, actually, this isn't the speaker that I'm asking about. The ones I am asking about were probably older.
Here is a picture for reference:
(http://www.audiocircle.com/image.php?id=94989)
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maybe this one. Zak
(http://www.audiocircle.com/image.php?id=139356)
(http://www.audiocircle.com/image.php?id=139353)
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1996 Stereo Review Buyer's Guide:
Super Tower/R Special Edition
Two 15" and one 10" woven-carbon woofers, two 5" woven-carbon cone midranges, two 1" Focal dome tweeters, and one 2" ribbon supertweeter. Bi-wire/biamp terminals. 100lb.
No other specs.
Edit
1996 Audio magazine's Equipment Directory
20-50k +0 -3; 94 dB; x-o 80, 600, 5k, 15k; 4 ohms; 18" x 18" x 52"; 175lbs; $3400/pair
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Thanks, but what a tease! However, it looks like the newer versions just replaced the mids with ribbons, so the specs were probably the same.
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The difference in sensitivity (90dB vs 94dB) is most likely 1w/1m vs 2.83v/1m, which is 2 watts into 4 ohms; 94-3dB = 91dB
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I have a pair like this with all the original docs including assembly instructions.
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I'm looking for a suitable 15" woofer replacement for these, preferably w the phase plugs. I've asked John and he has no suggestions.....He says he doesn't know if the 15's listed at the bottom the driver replacement thread will work or not, the GW-15PC-8
One of my woofers has started to crackle under high volume loads.....
Thanks
Rick
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I'm looking for a suitable 15" woofer replacement for these, preferably w the phase plugs. I've asked John and he has no suggestions.....He says he doesn't know if the 15's listed at the bottom the driver replacement thread will work or not, the GW-15PC-8
Unfortunately, probably due to the car stereo Boom crowd, most 15" woofers are 4 to 2 ohms in impedance, and have a high Qts measurement, better suited for sealed or infinite baffle use. An 8 ohm, low Qts woofer, like Brian designed and used for his ported speakers, is getting very hard to find. As such, if you need replacement VMPS woofers, they'll have to be used, from another owner or eBay, or something new, and hope that it works! So, looking at different drivers, I don't see too many possible usable choices. Looking at the specs, I think these might work, but at this point, it's a trial and error, buy it and see how it sounds, situation.
In order of preference:
The Goldwood woofer that Brian appeared to be using in later Lager subs.
http://www.parts-express.com/goldwood-gw-15pc-8-15-heavy-duty-woofer-8-ohm--290-338 (http://www.parts-express.com/goldwood-gw-15pc-8-15-heavy-duty-woofer-8-ohm--290-338)
A similar Parts Express Dayton woofer, with a bit more low end extension.
http://www.parts-express.com/dayton-audio-dc380-8-15-classic-woofer--295-325 (http://www.parts-express.com/dayton-audio-dc380-8-15-classic-woofer--295-325)
A MCM Electronics woofer that has decent specs, and is cheap enough to try.
http://www.mcmelectronics.com/product/MCM-AUDIO-SELECT-55-2974-/55-2974 (http://www.mcmelectronics.com/product/MCM-AUDIO-SELECT-55-2974-/55-2974)
A Parts Express Dayton pro woofer, that has very good extension, but may be too efficient.
http://www.parts-express.com/dayton-audio-pa380-8-15-pro-woofer--295-034 (http://www.parts-express.com/dayton-audio-pa380-8-15-pro-woofer--295-034)
An Eminence pro woofer, that has slightly less bass extension, but again, may be too efficient.
http://www.parts-express.com/eminence-delta-15lfa-15-low-frequency-driver--290-417 (http://www.parts-express.com/eminence-delta-15lfa-15-low-frequency-driver--290-417)
Also, there's a pair of older 15" VMPS woofers for sale now on ebay. They might work too.
http://www.ebay.com/itm/VMPS-SUPERTOWER-II-R-15-SUB-WOOFERS-PAIR-/182063304383?hash=item2a63d18ebf:g:A5EAAOSwuAVWwpFj (http://www.ebay.com/itm/VMPS-SUPERTOWER-II-R-15-SUB-WOOFERS-PAIR-/182063304383?hash=item2a63d18ebf:g:A5EAAOSwuAVWwpFj)
Good luck!
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That MCS woofer is real cheap and has a much higher Qts than its specs state according to one of the reviewers. around 2, I would try it in a heart beat but for its power handling....another reviewer says dont throw more than 75-100 watts at it.
The Used ebay woofers are interesting but the seller wants too much to ship them.....Could get 2 new GW's for little more.
Probably gonna try the 1st GW 15 from Parts Exp. when I cant stand the rattle anymore. I dont play them loud enough to hear the problem very often. So I have time to look for a while.
Thanks
Rick
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Thanks, but what a tease! However, it looks like the newer versions just replaced the mids with ribbons, so the specs were probably the same.
That's correct.
I never liked any of the so-called "Dynaribbons" which Brian got closeout from Just Speakers in San Francisco, long gone. I would prefer the earlier WCF 5.25" mids. The Dyna's sound kind of thin and plasticky. I feel quite sure it would have worked much better w/a small low-pass pole added to the mids, but Brian was dead set against doing this till he finally added such pole to the Neo planars, a few years prior to the end.
The worst of this series is the brief period with both the Dynaribbons and the metal domes. This particular pairing had high fatigue factor.
The best pairing would have been Brian's own poly 5.25" w/ the fiberglass Focal dome, but I don't think we made any such speakers.
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The difference in sensitivity (90dB vs 94dB) is most likely 1w/1m vs 2.83v/1m, which is 2 watts into 4 ohms; 94-3dB = 91dB
Brian over stated sensitivity about 3-4 dB. He added 3 dB for the PR and 3 dB for the mid bass, both completely wrong. A PR acts as a port. It extends cut off but does nothing to general sensitivity. Ditto the mid bass, which increases extension.
This model is about 88 dB.
15" and 10" both 8 Ohm. There's a large value R (can't remember the value, maybe 15 R) on the mid bass. Even though they are wired parallel, it's not 4 Ohm nominal, more like 6 Ohm.
What I think makes them current hogs is low-impedance (caused by the xo) coupled to moderately severe phase angles.
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Just for another data point I have the 15" Goldwood GW-15PC-8 (8 ohm) from Parts Express in my (original) Supertower/R and have been very pleased with them.
Ed
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Just for another data point I have the 15" Goldwood GW-15PC-8 (8 ohm) from Parts Express in my (original) Supertower/R and have been very pleased with them.
Ed
Was the Goldwood 15" woofer physically a drop-in replacement? No modifications needed to make it fit the existing cut out? Also, no crossover changes required? Plus, it's good to hear from someone that tried the Goldwood, and that it worked. Thanks!
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I brought a pair of ST/R with all new drivers (drivers purchased from Brian) and they had the 15" Goldwood drivers in them. 12" Misco LC12W-8A Morel MDT30s. Zak
(http://www.audiocircle.com/image.php?id=105680)
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I love the ST/R. I owned the earlier version, IIRC w/Brian's own mid range design, Morel MDT30s, and either the original Japanese JVC planar super tweeter or the latter Taiwan clone (one step down in performance). Of all the more affordable used models, for me the sweet spot is a superb condition ST/R SE w/round over vertical corners. The ST II/aR and ST III lean toward being ungainly and cosmetically, they simply over power the room, casting such an insanely huge shadow.
The ST/R SE is just shy of too much, the larger speaker certainly beyond too much. In anything approaching a normal sized room, the size to output ratio favors the "less large" model ("smaller" just doesn't work in this context).
ST/R came standard w/the WCF mid cone. WCF did not catch on as a universal cone material for a very simple reason. It's best and worst virtue is its self-damping quality. Damping makes for an infinitely smooth natural roll off, never requiring a LP xo. But the same quality also tends to over damp leading edge transients, minimizing dynamic snap and liveliness.
I would search out four of Brian's own poly cone steel frame mids (can't remember whether foam or rubber surround), and install these where are now WCF mids. To smooth top end response I'd add a small LP coil to the poly cone.
The mid bass to mid range xo is QSO, and I might change this to a standard xo: 2nd order LP on the mid bass, first or second order for the mid range (all electrical slopes, acoustic would be different).
With these changes I think performance would be solid, and something I could live with for a very long time (with our Space Generators behind it to boost reverberant field performance).
Probably ideal to replace the PR w/four rear firing ports, which can be run open or sealed, same as adjusting PR mass. If I did this, I'd plug the pedestal front opening and seal the pedestal to the enclosure volume. I can't remember why, but I recall learning that the PR works better side-firing, and Brian finally switched to this location in his last model.
One last neat trick would be to make a small sub enclosure to seal the 10" mid bass.
It's a Frankenstein, but if you start w/$400/pr speakers who cares?
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So, how similar to each other were these two? One just a newer version of the other? I've always loved the look of the rounded Oak cabinet corners, and the D'appolito driver layout of the top speaker. Just wondered how they sounded?
(http://www.audiocircle.com/image.php?id=94989) (http://www.audiocircle.com/image.php?id=105680)
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As you can see, the wave front of the SE on top beats the lower standard ST/R. But the lower one has Brian's own mid design, which I prefer overall vs. the WCF mids on the SE, but I'm nit picking. Overall the upper SE speaker is better, by good margin. Better domes too, by good margin, never really liked the Morel domes much at all.
I kept hounding Brian to switch to the Scan Speak soft dome D200009, and he did later, and those are the best domes he ever sold, but the Focal are not bad at all, much better than the Morel (almost anything is, the Morel are just kind of fuzzy sounding...the 30s are better than the 29s, but neither as good as the Focal and Scan Speak.
If I had room I'd have a pair just for old times sake, and they sound very good for a cone/dome system...it's just that I don't really have any interest in cones/domes any more, except for maybe the insanely expensive stuff.
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Stimpy, yes the Goldwood 15" woofers were drop-in replacements. No need to modify the cabinet. Brian only specified a crossover change when I replaced the 12" original poly driver with the Misco LC12W-8A. He said there isn't a crossover change needed if only the 15" is replaced. He suggested a low pass coil change from 1.0 mH to 2.8 mH along with the Misco driver. This also moved the woofer to mid crossover from 600 Hz to 450 Hz. Brian told me there is a response dip at 1 KHz in the Supertower/R and Tower ii, and this coil change along with the driver change should mitigate it. It did, somewhat, so I kept tinkering. I changed (unwound) the coil to 1.4 mH. This also changed things but I am not sure it improved anything. Recently I cleaned the L-pads with DeOxit Gold (thanks James) and that made a huge improvement in clarity, so now I am thinking I need to go back to Brian's 2.8 mH coil value. Maybe the improvement at 1 KHz with the 2.8 mH coil was masked by the dirty L-pads. I see another Parts Express purchase in my near future.
For the past couple weeks I have had my Supertowers apart trying to figure out how the woofer to mid series crossover works, where the break points are, and what the "correct" L and C values should be for the drivers that are in the cabinet. I have an audio signal generator and volt meter. I send 1 VAC 50 Hz to 1 KHz to the speaker terminals and sweep the signal until I see 707 mV across the driver which should be the break point for that driver. Sounds simple but it has been more complicated that I expected as every component affects every other component and I am having a difficult time isolating signal paths to determine which frequencies go through which drivers. Can someone with a bigger brain shed some light on this?
Ed
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Unfortunately, it is impossible to isolate poles in a QSO crossover, which means there can never be modeling software, which is the main reason it's not more commonly used.
I think you can find the crossover poles by testing as you describe, but changing one leg also changes the other, so it's impossible to isolate the two.
At least one crossover design genius is on my speed dial. If I had my druthers, I'd probably send the drivers to him to model. Based only on aural memory, and some intuition, I suspect a good option for this model is 2nd order LP for the mid bass (really, the coil value is so low that it has little affect on the 15"), and 2nd order HP for the mids (no QSO....these slopes are electrical, acoustic unknown). As stated earlier, I prefer Brian's own mid cones over the Taiwan Versa Tronics WCF, but Brian's likely benefit with a small value LP coil (Brian would never approve) while the WCF would degrade with such coil. Adding this LP coil may require moving the treble pole a bit lower, but it's so high (estimate 5k Hz) that there is plenty of margin for this mod, and it's easy, just add cap value.
Brian's LEDE sound room was so dry on the speaker end that it tended to mask certain qualities that were audible in normal applications. It's interesting to me that our Space Generator reverberant field system, coupled with main speakers having a very tightly controlled radiation pattern, replicate in a normal sound room the best qualities of Brian's LEDE sound room.
One of the benefits of QSO for OEM is that it magnifies the value of the HP cap bank for the mid range, allowing a much smaller value than a non-QSO xo. I wonder if this cost-savings affected Brian's preference, but it might have been of no consequence.
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ST86,
Thanks for the Goldwood feedback. That's very good info. Every VMPS owner needs to know these things, since VMPS spare parts aren't exactly plentiful! Back-up drivers have to be tried and evaluated.
Good luck on figuring out your crossover too. And if your Supertowers have Brian's typical series crossover, I expect it won't be an easy dissection. It's no wonder you can't isolate components if the speaker does have series wiring.
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James, Stimpy, thanks for the feedback. I am going to go back to Brian's value of 2.8 mH and re-measure.
To follow up on the Goldwood woofers I use the smaller 12" Goldwood GW-12PC-8 for the lower woofer in my Tower ii. Those were a very tight fit, so much so that when I refinish the cabinet if the weather ever gets warm enough here in MA to work in my garage I will open the cutout with a rasp or hand planer.
Ed
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There are 2 sets of speakers pictured in this thread....I have the bigger ones at the top....Not the smaller ones posted second....Do these suggestions apply to them or the smaller ones or both?
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My experiments with the crossover and recommendation of Goldwood 15" woofer apply to the older Supertower/R, the one pictured with black painted front and non-rounded corners.
Ed
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Heres the crossover schematic for the larger version
(http://www.audiocircle.com/image.php?id=140547)
The image is getting shrunk somehow......I can read fine on my puter but here and DL version is smaller???
I uploaded a 964kb file and when choose save as get a 44kb file?
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You would not believe how fast Brian would assemble those xo's. Conversely..........
We had a customer call for a copy of this exact xo diagram. He purchased ST/R kits many years prior, and never assembled them.
Besides building the xo, his next biggest problem was giving his cats the sad news that he had found a better use for their "cat condo," AKA empty ST/R enclosures...
My very very first VMPS buyer was a local guy in Novato, Marin County, who bought an Original Sub kit. Debra bumped into him years latter, at which time he mentioned they still awaited assembly.
The best of intentions...
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When I got my kits I couldn't put them together fast enough....and being slow and careful building the XO's, because I understood how important it was not to make any errors, was a difficult process at my relatively young age then. I remember staying up way too late and the forcing myself to sleep so I could stay coherent, and make sure they were right. I sure glad I did because my ears and friends have enjoyed them for many many years now.
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The R value on the mid bass: is that 30R crossed out, replaced by 11R?
The bass and mid bass were each 8 Ohm nominal. If yes to above, the respective nominal impedance were:
6.6 Ohm (30R)
5.6 Ohm (11R)
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That schematic looks like mine except for the C and L values. The series resistor on my 12" midbass was 25 ohm, not needed with the upgrade to the Misco driver. Your crossover cap to the mids is 4.19 uF and mine is 54 uF? That is quite a difference, everything else is pretty similar. What is the inductor value between woofer and ground? Can't read the drawing.
My Supertower schematic is posted somewhere on another thread, I can repost here if there is interest.
When you used "save as" did it give you a list of sizes? Some programs will resize large documents to "standard" size for email.
I was the same way building my Supertowers. Long nights, many checks to be sure everything is right, and then the payoff of countless hrs of listening enjoyment.
Ed
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I wish there were enough owners, with crossover schematics, that we could start a new thread, and Pin it. Nothing but VMPS documents and schematics for current and future owner use. While I respect that this was intellectual property for Brian, but it seems that most of this stuff was only filed within Brian. We need a record of his notes, at least as much as we can find. I don't think there will be a future VMPS legacy if we don't attempt this.
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Stimpy,
I agree. I don't think for example there should be a problem posting whatever paperwork was provided in the kits, which would include schematic, parts list and build instructions.
Ed
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The R value on the mid bass is 22 ohm.
The coil to the woofer/midbass is 1.5mH.
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That schematic looks like mine except for the C and L values. The series resistor on my 12" midbass was 25 ohm, not needed with the upgrade to the Misco driver. Your crossover cap to the mids is 4.19 uF and mine is 54 uF? That is quite a difference, everything else is pretty similar. What is the inductor value between woofer and ground? Can't read the drawing...
Ed
I would bet the Misco was a pretty huge upgrade from Brian's 2710 Gefco 12" mid bass (the only VMPS 12" w/radial ribs, small magnet, and 1.5" VC), probably made in greater quantity than any other VMPS driver. The 2710 had great mid bass dynamic snap, but after hearing it forever, both alone and in systems, I was convinced it really needed either to be crossed lower or redesigned (it was unchanged my whole time there). Crossing the 2710 so high shifted higher all poles on the smaller drivers, increasing system global power handling. (Crossing the 2710 higher has no effect on its power handling, but it moves the mid range HP pole higher, which increases mid range power handling.) The higher the 2710 is crossed the more distinct is its cupped hands effect. There is much less cupped hands effect in use in the enclosure, but still too much for my taste.
If the Misco mid bass swap maintained the same L, the lower impedance (no R) moves the pole lower. That, coupled with what I presume is less natural extension than the 2710, required the increase in C value, which moved the mid range pole lower.
I presume the increase in C value is not linear. IOW, 2x the C value does not equal one octave lower, as would be the case with a straight first order electrical pole, because QSO is not linear in that way. Also, the lower mid bass impedance and different mid bass parameters directly affect the mid range pole, in ways I can not explain.
The person I know with the most knowledge about QSO is Fritz of Fritz Speakers, a great guy who makes possibly the best performing small speakers ever.
I presume the Misco swap is a big performance upgrade. FYI: QSO is 1st order electric LP, 2nd order electric HP.
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Performance upgrade with Misco? Yes. The difference was obvious, even to me.
Brian told me the 25 ohm on the 12" was to level match (acoustically) the 12" with the other drivers and the resistor was not needed when switching to the Misco. Was unaware of the effect the resistor has on crossover performance.
54 uF high pass cap to mids with Misco is pretty close to original value with 2710, maybe an increase of a few uF.
Original woofer-to-ground inductor with 2710 1.0 mH, changed to 2.8 mH with Misco driver.
Oh, and I should also mention mids were upgraded from the grey poly cone Peerless to what Brian referred to as "classic mids" that look strikingly similar to a four ohm version of the Dayton Audio DCA 130A-8. I don't remember if I had to change the high pass cap value to 54 uF when I updated the mids or the 12".
Ed
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(http://www.audiocircle.com/image.php?id=141189)
I got the Goldwood woofer, here's pic showing the diff in magnet size, GW is also much heavier. Goldwood is slightly bigger in outside diameter and will not fit in stock hole. I had to enlarge the hole slightly about 1/16 all around.
Sound wise, it rocks....just like the original. The bass extension may be greater w the GW. Very happy my crackle is gone.
Looking Misco's website today {original woofer manufacturer}, they certainly don't seem like a high end company at all....Don't know if it was this way 30 yrs ago....
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Why on earth would that woofer on the L outperform the one on the R? That makes absolutely no sense at all! None!
/sarc off
Doesn't that just seem wrong when one woofer requires 1/16" larger radius than the another?
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This sucks. I need to spend more money and buy another of these and replace the other working fine stock woofer. The bass out of the GW side is amazing, I like it....and it's not even got but a couple hours on it....And this is after upgrading the PR's last year.
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Hey RSorak Parts Express has a coupon, (use code TAX2016) good threw the weekend. I think the Goldwoods are worth it thought. On my SuperTower /R the 15" driver is not recessed, so no cabinet adjustment. Good Luck Zak
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I got the Goldwood woofer, here's pic showing the diff in magnet size, GW is also much heavier. Goldwood is slightly bigger in outside diameter and will not fit in stock hole. I had to enlarge the hole slightly about 1/16 all around.
Sound wise, it rocks....just like the original. The bass extension may be greater w the GW. Very happy my crackle is gone.
Looking Misco's website today {original woofer manufacturer}, they certainly don't seem like a high end company at all....Don't know if it was this way 30 yrs ago....
That new Goldwood is nice. It looks good too, with it's cast frame, as well. It should mount it backwards, facing in, to show off the basket! :o
As to Misco, they're not a high end company. They're a speaker driver company, for all speaker types. Brian used to 'I believe' supply his woven carbon fiber material, and Misco would manufacture the woofers. So, Brian probably liked them, since they'd build custom orders. And their prices are decent! :)
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(http://www.audiocircle.com/image.php?id=141189)
I got the Goldwood woofer, here's pic showing the diff in magnet size, GW is also much heavier. Goldwood is slightly bigger in outside diameter and will not fit in stock hole. I had to enlarge the hole slightly about 1/16 all around.
Sound wise, it rocks....just like the original. The bass extension may be greater w the GW. Very happy my crackle is gone.
Looking Misco's website today {original woofer manufacturer}, they certainly don't seem like a high end company at all....Don't know if it was this way 30 yrs ago....
Why on earth would that woofer on the L outperform the one on the R? That makes absolutely no sense at all! None!
/sarc off
Doesn't that just seem wrong when one woofer requires 1/16" larger radius than the another?
I have a set of Super Towers. Originally I put them together as a kit in 1980. Upgraded the 15, the 12, and the mids in 1989 or so when the surrounds disintegrated. Got everything from Brian.
The 15's I have are the white ones...but, they have the same number on the back as these, X3967 that I've seen on other posts..I had heard they were the same woofer, something about the white just being painted on?
Anyway, If I can get a good shape replacement pair of the X3967 15, but not white, should I do that? Or, should I replace with the same 15" Goldwood that this person did?
What do you two think? James Romeyn because you worked there and know your stuff, and RSorak because you actually did it.
These are my speakers (sorry about the crappy appearance...they've been through a lot). Also, wondering if the carbon fiber mids (the one's that have the checkerboard carbon fiber appearance) are worth an upgrade. I think I remember you James mentioning you did not like them compared with the one's I have already.
(https://www.audiocircle.com/image.php?id=213874)