My updated ST/R's done

mosawdust · « **on:** 13 Jan 2011, 10:15 pm »

I really want to thank Big B for all his time and help. He has been extremely patient with me through all this and took the time to answer all my questions and emails. Thanks B.

This whole project started by replacing the PR's that had rotted away. After I got those and saw how nive they looked I figured I may as well see about replacing the woofers and the mid bass drivers with new updated ones. Well those looked so darn nice I may as well replace the old mids and see about the tweeters now. Before I stick the new drivers in I probably should add all the internal bracing everybody talks about being as the front panel was starting to seperate at the center brace. Well, now I didn't like the way the new Super Tweeter fit and looked with the adapter (no offense B) so I plugged all the tweeter holes, bored new holes in the same exact spots and veneered the front and back. Now they looked so good I couldn't put all those nice new drivers in there with the old crossovers. Another call to Big B. So, finally this is how they ended up.

Finally got them finished today and playing.

WOW!!!

Brian

John Casler · « **Reply #1 on:** 13 Jan 2011, 11:22 pm »

Brian,

Yes WOW is right.

Fantastic Job!!!

It is amazing how many of the Classic VMPS speakers are still in the field.

mosawdust · « **Reply #2 on:** 13 Jan 2011, 11:25 pm »

Thanks John, I very please with the overall end result.

Brian Cheney · « **Reply #3 on:** 14 Jan 2011, 12:17 am »

Truly an amazing job. Wish you had been there 20 years ago to make the boxes for us from scratch. My congrats and admiration.

mosawdust · « **Reply #4 on:** 14 Jan 2011, 10:53 am »

Thanks for the kind words Big B. Excellent job on the new x over. I was very excited to see the toggle switch eliminated and the 15" and 12" and now on their own set of binding posts. They are still breaking in so it might be a little early to really give a fair judgment.

The Bass has improved immensely. It now sounds fast, tight and clean. Between the new drivers and the bracing, which I added a substantial amount of, it's literally a difference of night and day. I was initially pretty concerned with the amount of bracing I added using up too much volume area but that has proved to be not an issue.

This is like starting all over with a new speaker. I tried to implement as many of the TWEAKS as I could that I learned from the forum.

Internal Bracing
Covered all the driver baskets with mortite
Analysis Plus wire to the woofers
Lambs wool in the mid enclosure
Reversed the PR slot.

Ok. The lambs wool didn't work here for me. The mids are the area that I seem to be not to excited about so far. Not even through the first song I pulled the lambs wool out and stuck the fiberglass insulation back in. I don't know why but the mids are sounding like the drivers are in a hollow box and the lambs wool seemed to enhance it. Not sure what’s going on there. Not sure if its simply because they haven't broke in yet or what. So far I feel that the old drivers with the phase plugs were superior to the new ones. I'm still trying to make adjustments to get it dialed in.

Any thoughts here B ?

I couldn't be more happy these are finally finished because my 50 year old 115 pound body is pretty darn tired of moving around these cabinets.

Venkman · « **Reply #5 on:** 19 Jan 2011, 03:38 pm »

Wow!

Fantastic job! They look brand new. Are those the upgraded 15's? I may PM you at some point for some tips on your tweaks.

Again, great job bringing new life into those speakers!

flintstone · « **Reply #6 on:** 19 Jan 2011, 04:26 pm »

WOW.......the nicest looking pair I have come across

(those look like some of the last made ST/R's....1996 or so?).

Dave

Brian Cheney · « **Reply #7 on:** 20 Jan 2011, 12:55 am »

sawdust:

If the mids sound hollow, I'd do the following checks:

1. Make sure the drivers are in series with each other. That means the + wire from the xover caps attaches to the + terminal on the lower mid, the neg. wire from the xover attaches to the neg. terminal on the UPPER mid, and there is a jumper connecting the neg. lower to the pos. upper terminals. Check with a 9V battery to make sure they are in phase, with the + battery applied to the red wire after the xover caps and the - battery applied to midrange ground. Both cones should move forward when this is done.

2. If this checks out, add value to the midrange crossover 1uF at a time to fill in the in-phase notch. This means wiring additional caps of this value in parallel with the midrange crossover cap bundle. Go slowly and listen. Stop when the hollow sound is gone and the mids sound as clear as possible.

Let us know what you think. The new mids should be at least as good as the old.

mosawdust · « **Reply #8 on:** 21 Jan 2011, 03:17 pm »

Quote from: Venkman on 19 Jan 2011, 03:38 pm

Wow!

Fantastic job! They look brand new. Are those the upgraded 15's? I may PM you at some point for some tips on your tweaks.

Again, great job bringing new life into those speakers!

Thanks for the kind words. They are cast iron frame mega woofers.
Feel free to pm me.

mosawdust · « **Reply #9 on:** 21 Jan 2011, 03:27 pm »

Quote from: Brian Cheney on 20 Jan 2011, 12:55 am

sawdust:

If the mids sound hollow, I'd do the following checks:

1. Make sure the drivers are in series with each other. That means the + wire from the xover caps attaches to the + terminal on the lower mid, the neg. wire from the xover attaches to the neg. terminal on the UPPER mid, and there is a jumper connecting the neg. lower to the pos. upper terminals. Check with a 9V battery to make sure they are in phase, with the + battery applied to the red wire after the xover caps and the - battery applied to midrange ground. Both cones should move forward when this is done.

2. If this checks out, add value to the midrange crossover 1uF at a time to fill in the in-phase notch. This means wiring additional caps of this value in parallel with the midrange crossover cap bundle. Go slowly and listen. Stop when the hollow sound is gone and the mids sound as clear as possible.

Let us know what you think. The new mids should be at least as good as the old.

#1 is the problem. I have them wired with both wires from the xover to the lower mid and jumpered straight up to the upper mid. (+ to + and - to -) Will correct and see how that changes things.

Thanks B.

Brian Cheney · « **Reply #10 on:** 21 Jan 2011, 04:50 pm »

That will give you a 2 Ohm impedance and change the xover frequency up several octaves, leaving a large gap.

DFaulds · « **Reply #11 on:** 21 Jan 2011, 05:34 pm »

I would just like to add that even though these aren't quite in the vintage realm, they certainly are classics.

Brian, do you keep tabs on any of your earliest customers? It would be especially interesting to see who still has some of the VMPS flagship speakers still in use, like the ones that I think used Strathearn planar/ribbons. I have some old VMPS literature, and you certainly have produced some very interesting designs over the years.

Brian Cheney · « **Reply #12 on:** 21 Jan 2011, 06:18 pm »

I hear from owners of very early VMPS speakers almost every day, and there are over 20,000 pair in the field. We supply parts to them as needed. I do not believe in throwing speakers away, or selling them at a few cents on the dollar, just to obtain the latest and greatest.

Yes, I have built various kinds of speakers over the years, and still look to improve on what's gone before. The RM50 is our first Bipole, and performs at a high level, at what I consider a reasonable price for value received.

DFaulds · « **Reply #13 on:** 21 Jan 2011, 06:52 pm »

I hope to hear the RM50's some day. Have any been sold in Ohio?

John Casler · « **Reply #14 on:** 21 Jan 2011, 08:43 pm »

Quote from: DFaulds on 21 Jan 2011, 06:52 pm

I hope to hear the RM50's some day. Have any been sold in Ohio?

The Bybee equipped SHOW Pair will be traveling "through" OHIO soon, on their way to Maryland.

They were just purchased and the order is being processed as I type.

They will be joining a very nice SYSTEM with JC-1's on top and Parasound 3500's on the bottom.

This pair sounded incredible at the show, in a big BIG room.

mosawdust · « **Reply #15 on:** 22 Jan 2011, 09:54 am »

Quote from: Brian Cheney on 21 Jan 2011, 04:50 pm

That will give you a 2 Ohm impedance and change the xover frequency up several octaves, leaving a large gap.

Thanks B, I'm going to try and get these fixed today. I'm in the middle of painting the inside of the house for the wife. I promised her I would do this 3 years ago when we bought it.

Quote from: DFaulds on 21 Jan 2011, 05:34 pm

I would just like to add that even though these aren't quite in the vintage realm, they certainly are classics.

Brian, do you keep tabs on any of your earliest customers? It would be especially interesting to see who still has some of the VMPS flagship speakers still in use, like the ones that I think used Strathearn planar/ribbons. I have some old VMPS literature, and you certainly have produced some very interesting designs over the years.

I purchased mine in 1993 and I don't think I will ever part with these. Still have the original brochures.
I still regret selling my ST III's. The 4 of these together made for some very empty walls.

Quote from: DFaulds on 21 Jan 2011, 06:52 pm

I hope to hear the RM50's some day. Have any been sold in Ohio?

Same here. They just look incredible.

DFaulds · « **Reply #16 on:** 24 Jan 2011, 12:38 pm »

Quote from: John Casler on 21 Jan 2011, 08:43 pm

The Bybee equipped SHOW Pair will be traveling "through" OHIO soon, on their way to Maryland.

They were just purchased and the order is being processed as I type.

They will be joining a very nice SYSTEM with JC-1's on top and Parasound 3500's on the bottom.

This pair sounded incredible at the show, in a big BIG room.

Well, unless the driver has them hooked up and playing while they're traveling through Ohio, I guess I won't be able to hear them.

John Casler · « **Reply #17 on:** 24 Jan 2011, 11:44 pm »

Quote from: DFaulds on 24 Jan 2011, 12:38 pm

Well, unless the driver has them hooked up and playing while they're traveling through Ohio, I guess I won't be able to hear them.

That would be funny having them strapped to a Semi and Playing Cross Country on the Interstate.

Only problem is the driver would probably want to play the Soundtrack to Smokey and the Bandit, or Cannonball Run

mosawdust · « **Reply #18 on:** 25 Jan 2011, 09:06 pm »

Finally got the wiring fixed today and put the lambs wool back in again. Spent quite awhile adjusted the level controls and placement of the speakers themselves and all seems considerably better. MUCH BETTER. Thanks for the help B.

krikor · « **Reply #19 on:** 25 Jan 2011, 10:09 pm »

I've got a line on a pair of local VMPS Tower II speakers... wonder if it might be worthwhile to try a rebuild them.