[dBs]

I searched the forum and found a VMPS Super Tower /r schematics thread, but it was brought up that there were many variations of these and a general schematic wouldn't be helpful.
I'm enclosing a pic of my speakers in my garage. They were bought from a dealer in Johnstown,PA, I'm guessing in the late '70's. I did two further Cheny modifications on them before they sat for close to two decades in my spare garage.
I've two questions-are they worth restoring?
Will the price be astronomical?
Actually 3 questions--Can I find someone to help me?

I have two spare 15" woofers I can install, (spare's VMPS sent me years ago), but the one 12" is busted up pretty good. The passive radiators' foam surrounds are shot-but I might be able to refoam them?
I haven't tested the other speakers yet. They look alright, and I figured--actually I don't know how I'm going to test them. I have a multimeter I don't know how to use.
The college neighbor is coming home this weekend, and I'd like to have him move these upstairs, but I'll wait to hear what you say.
I'm going to need a quite a bit of help on these.
I also have a rebuilt Van Alstine Dynaco 400 and Pat 5 I believe, but that's a later story. All these components are from a time when I thought I had money!I can't find the documentation for any of these.

[ST86]

Hi  DBs.  I own a pair of Supertower/R, have done numerous driver and crossover upgrades as well as refoams.  I have schematics that I can copy and send to you if you wish.

Your rehab will come down to how much time and money you want to spend.  New drivers are an easy and more expensive fix and give better performance.  Most likely the drivers you have now can be refoamed and used.  A cheaper alternative, will  get the speakers working but not to the level of new drivers.  Your choice.

You can try refoaming the 12” driver and 15” passive.  From what I can tell from the picture the 12” cone looks to be creased in some places which could affect performance.  Are the cones on the passives disconnected?  I had to replace mine because they dry rotted to the point where the cone came off the driver body. 

Gently run your finger around the foam surrounds of all the drivers.  If they crack or crumble they need to be refoamed or replaced.

I have two 12” original drivers for sale.  See my recent post.  They have been refoamed but work fine.  Let me know if you are interested.  Not the latest technology but an inexpensive alternative.

Being a Supertower/R (and Tower ii) owner I am biased and would suggest keeping them and getting them working to your satisfaction.  You will be pleasantly surprised when you hear them.

Cheers!
Ed (ST86)

[dBs]

That's all I needed to hear. I'll have the boy help me move them up this weekend.
All the foam on the drivers seems to be in really good shape. The  mangled 12",  I'll give a better look at this weekend.
Same with the PR's although they really look good outside of a 50 cent sized hole in the foam on each, (I may find an old mouse house in there when I start digging around). I did just notice I repaired the PR foams previously and it looks like I had used some clear silicone sealer on them--probably something like bathtub caulking. I don't know if that had been recommended by someone or if it was just something I did on my own    I know it was recommended to me by the dealer to soundproof the insides with automotive undercoating for sound dampening, but I noticed 20 years ago that stuff had become brittle and was probably reflecting more sound than damping it. There's probably better deadeners available nowadays. He had his demo Super Tower /R's dampened inside with pounds of modeling clay he heated and sliced with a cheese slicer.
The PR's had quite a bit of added mortite on them, to tighten up the response, and I'm guessing it's a common problem for PR's to sag and deteriorate moreso than other drivers.

[ST86]

If the passives have ropes of Moretite putty on them, maybe secured with hotmelt glue, then they are the older style passives.  Over time all that added putty pulls the cone away from the rest of the driver and they fail.

When I upgraded, the passives came with a small slug of putty in the center.  Brian told me this is because those passives have a lead slug in them and there isn't a need for all that putty on the cone.  I still suggest doing the finger-around-the-surround test on all the cone drivers.  My mids and 12" drivers looked fine until I did that and the surrounds crumbled.

A hand truck works great to move these speakers.  Put a towel around it if you are concerned about scratches.

Ed

[underdawg]

st86 i could use a copy of the schematics if you dont mind, i have external crossovers brian made for me waiting to installed, he was going to tell what to do, but we never got to have that conversation.


As for the rebuild yes its worth it, I rebuilt mine. The have been the best speakers I have owned for solid state or tube.
see my rebuild pics below.

[dBs]

Yes, I was admiring these speakers in another thread! I've been studying them trying to figure them out. That doesn't even look like a 12" speaker in there!
And I heard you mention those external crossovers previously--it scared me! What I remember, the crossovers in mine weren't too many parts. Are  the external crossovers for further isolation of interference?
I've been looking for the thread where your drivers are mentioned. They're beautiful. Are the 'bars' on the 15" DIY?


It's going to be close quarters on the walls these speakers are going against. I bought a Mitsubishi DLP 82", and with the speakers beside them, I'm figuring there's going to be 22" on each side. I've never played them that close to a wall before. I'm a little worried about that.
Next step is to move them upstairs, take the drivers out and inspect, and photograph everything, so I can get the numbers off of everything, and photograph the existing crossovers.

[ST86]

Underdawg, PM me your address and I will send you the schematic. 

[underdawg]

Yes, I was admiring these speakers in another thread! I've been studying them trying to figure them out. That doesn't even look like a 12" speaker in there!
And I heard you mention those external crossovers previously--it scared me! What I remember, the crossovers in mine weren't too many parts. Are  the external crossovers for further isolation of interference?
I've been looking for the thread where your drivers are mentioned. They're beautiful. Are the 'bars' on the 15" DIY?


It's going to be close quarters on the walls these speakers are going against. I bought a Mitsubishi DLP 82", and with the speakers beside them, I'm figuring there's going to be 22" on each side. I've never played them that close to a wall before. I'm a little worried about that.
Next step is to move them upstairs, take the drivers out and inspect, and photograph everything, so I can get the numbers off of everything, and photograph the existing crossovers.

yes damp bars on 15 are diy.
the external crossovers replace all of the internal crossover parts. I plan to go with the new external crossovers this summer, remove all drivers, parts, and wire once I see a schematic from st86.

[underdawg]

each speaker has a global grossover, then each driver is tweaked further with more crossover parts on each driver, at least mine are built that way.

[dBs]

A few pictures that might add information towards any help in me restoring these speakers.

[dBs]

I forgot to include that the old 12"pole speaker  number is X2710 1056 9620

[dBs]

I haven't abandoned this, there's just little new information. Evidently, the 12" #2710,  is pretty tough to come across. I'm looking into two options. Getting my damaged 12" refoamed and getting a new diaphragm, or installing an older pair of VMPS 12". Repairing the 12" would be nice because I wouldn't have to change crossovers.
Taking the insulation out of the towers tomorrow and moving them upstairs to start testing. Are people still using insulation as an inexpensive dampener?
I'm also interested in what people are using to dampen the walls of the cabinets. Although the spray-on undercoating was recommended to me in the late 70's this stuff now seems more hard and reflective than the wood itself. I'll have to find a spray or paint that dampens things up nicely.

[dBs]

As far as my 12"woofer problem goes, I'm going to buy member  ST86's 12" and install them. Although they won't be original, they will get me by until I can find areplacement  X2710 with phase plug.
A quick inspection of the cabinet reveals I'll have to buy a new switch in the upper cup, as the middle prong has busted off. I'm not sure what the name of the part is. This is in addition to the 15" foams I'll need on the PR's



Thanks so much to ST86, who is helping out tremendously on these. I have the willingness, but lack any kind of technical expertise.

[Stimpy]

Brian still recommended fiberglass insulation as cabinet fill material.  At least for woofers.  From what I've read, Brian didn't think that poly fill had enough damping effect, at low frequencies, to be a viable replacement for itchy old fiberglass.  So, keep using the fiberglass for damping, in the main cabinet.

As to ST86's woofers, I'd use 'em too, until exact replacements come along.  I'm a firm believer in using what you can.  I'd rather be able to hear the speakers, than have them sit unused, in a basement.  Now, one thing I'd compare between the 2 sets of woofers is magnet size, and the impedance of the 2 pairs.  Brian was good about designing woofers, for specific frequency responces, by altering the size of the magnet.  If the different woofers have roughly the same size magnet, and impedance resistance readings are close, I'd think you'd be OK to use ST86's woofers as-is, without needing any crossover tweaks.  If not already there, maybe add a L-Pad for the replacement woofers, so you'd be able to adjust it's level, if the sensitivity is slightly different between the replacements.

Finally, from your picture, I'm not sure what to call that broken terminal cup, other than that, a terminal cup.  Is it the input cup, for the speaker?  Maybe a picture, of the back of the speaker would help?  But if it is the input cup, Parts Express sells different types of speaker input cups.  Even terminals plates, that let you add multiple sets of binding posts, if needed.  Heck, with that schematic, you could build modern, external crossovers, that would make rebuilding the crossovers much easier, IMHO.

Oh yea, I wish we could start a Sticky here, with everyone submitting crossover schematics, if they had them.   A Tech database, similar to the thread that lists the known drivers, and their part numbers.  Every little bit helps...

Good Luck!

I haven't abandoned this, there's just little new information. Evidently, the 12" #2710,  is pretty tough to come across. I'm looking into two options. Getting my damaged 12" refoamed and getting a new diaphragm, or installing an older pair of VMPS 12". Repairing the 12" would be nice because I wouldn't have to change crossovers.
Taking the insulation out of the towers tomorrow and moving them upstairs to start testing. Are people still using insulation as an inexpensive dampener?
I'm also interested in what people are using to dampen the walls of the cabinets. Although the spray-on undercoating was recommended to me in the late 70's this stuff now seems more hard and reflective than the wood itself. I'll have to find a spray or paint that dampens things up nicely.

[DFaulds]

You should never use an Lpad on a woofer.  L-pads on a woofer will affect the woofers interaction with the crossover and will cause the crossover point to vary based on the L-pad setting.  It will also affect the woofer damping because of insertion of what is essentially variable resistors in both series and parallel with the woofers VC.

[John Casler]

A quick inspection of the cabinet reveals I'll have to buy a new switch in the upper cup, as the middle prong has busted off. I'm not sure what the name of the part is.

From your description, and the photo, the part you are talking about is the TOGGLE SWITCH that joins the WOOFER Section and the Tweeter/Midrange Section for single amping, or separates them for bi-amping.

I talked Brian into doing away with that TOGGLE and we just jumpered the binding posts if we wanted to single amp.

I had experimented and found that "jumpering" was sonically superior.

[dBs]

Yes, it's the upper cup. Your 'jumpering the binding posts' is an excellent discovery.  Do you have a diagram or photo of how this would look?

If I'm folloing you right, I'm still going to need a new upper cup switch. Could anyone please tell me the name of this switch and what specifications it should have? And if the photo didn't clarify, it isn't the upper 'cup' that is busted, but a terminal on the 2 way switch attached to the cup.

Good news. I was able to find Mortite locally over the weekend. I wish I would have been able to find the Mortite in black to blend in better, but. beggers can't be choosers.

[dBs]

Underdawg, I can see a big benefit of external crossovers would be manageability. I'm looking over my current crossover bundles and they take some focus to follow. My upper coil had broken off on one speaker tower  and I'm trying to determine where the leads go. I'm looking on my good speaker tower , and it's still difficult mentally sorting it all out.
 ST86's 12 drives came today in the mail. They're beauts! He's having me determine crossover values. He sent me the schematics, and I believe this is the first time I've tried to understand them. All the kits I ever seeembled from Mr Cheney were along the lines of "Take brown wire and solder to X" So, I never had a need to understand schematics.

What I have a question on is "B" and where this is connects to. It looks to me that "A" came of off post 5





My next post will be on crossover values.

[ST86]

Hi,

Lets take the top picture from top to bottom.  Point “B” is one end of the inductor.  That end should connect to pin 5 of the switch.  Locate that point on the schematic.  The other end of the inductor connects to the junction of one end of the capacitor bundle (this is the capacitor bundle for the mids, the largest capacitor on the schematic.  It is on the middle left of the schematic), the brown wire which goes to pin3 of the mids volume control, and the monster cable from the negative terminals of the 12” and 15” drivers.   Locate that point on the schematic.  It is just to the right of the 15” driver.  Point “A” is the junction of the other end of the capacitor bundle and the positive monster cable from the 12" and 15" drivers.  This should be connected to pin 2 of the switch.  Locate that point on the schematic.
 
Check the terminal cup. With it as shown in the lower picture (viewing it as if from inside the cabinet) is the positive (red) terminal on the left and the negative (black) terminal on the right?  If so, it appears your switch pin numbering is correct but you may have swapped the wire connections on pins two and five.  To check, be sure pin 3 in your bottom picture is connected to the positive speaker wire terminal.  If so, point “A” should be connected to pin 2, and pin 1 should be connected to the positive terminal on the other cup.  Pin 6 should be connected to the negative speaker wire terminal, pin 5 to point “B” and also the wire with black stripe (which is the negative wire from the mids, refer to the schematic) which now appears to be connected to pin 2.  Pin 4 should connect to the negative terminal on the other cup.

It may seem like a lot to sort out.  Take each connection one at a time.  Check each switch pin individually.

Cheers!
Ed

[dBs]

Upper cup crossover. The coil is unmarked.