A Real SL 2000 Hack. Replace stock (burnt voice coils) with "silk diaphragm dome ".

Tony M

I got this pair thanks to a member on this forum.

He posted somebody down in this area was selling a pair w/stands BUT they were listed in the "Furniture" listing I believe. 100.00.

After I contacted the seller and headed down there...50 miles away I think it was, the guy said he had a few more inquires wanting to buy them too. Beautiful stands came with them too.

I need to get back up with the member who alerted "us in this area" to them being for sale. I got lucky but only because of the member posting about them.

I think I can search that out and maybe find out...unless that member reminds me first.

They were a one owner set too. Ex. cond. one tweeter, pin / blade too.

Tony M

VSAT88 wrote: »

Holy Mackerel ! 35.00 FLAC that !

This CD does sound fantastic. Maybe the quality is what has raised the asking $ of this gem. here's mine. would I sell mine for 35? I don't know...

xschop

That is lucky. SDAs, especially CRS+ are impossible to find here in midwest. The only pair I stumbled upon year before last, looked like what Moses was sent down the river in.

Tony M

well...

I got antsy and went to do the other 6 tweeters last night. Started at around 11PM and finished at 4AM. I still have at least one old one left. There maybe a couple more in the back room.

I had a blast but my back and neck told me I over did it. I knew what to do, had the tools out already but carving into the back of the face plates was harder. I believe the plastic was a harder composition on most of these compared to a couple of others. I noticed in one of the pics, the plate mounting hole backs are different. That has to be why I had a tougher time carving. But still, it was rewarding and time flew by fast.

Here's a few picks;
















Now ready for testing in the future...

xschop

Looking good. Were you able to measure one of the magnet mount plates diameter?

I'm saving two of the next RD0 plate batch for the SL2K-V2 magnets and pair of new domes I still have.

Tony M

I don't think I know what you're asking.

Are you asking for the back of the plastic face plate where the magnet sits in's diameter?

I just got back from Lowe's where I looked over their machine screw assortment one more time but they definitely don't have what I need.

My main reason going there was to buy a nice 6" caliper. I now have one.

Tony

xschop

The width of the magnet plate that has the 4 tapped holes.

Tony M

10/4.

going out there now to measure.

xschop

Thanks Tony. I'll cut them out to mount either version at 2.690.

To confirm, the center to center of the tapped holes are 41mm?

Tony M

I'll go check...

Here's both ways ;

xschop

I got 1.590" so close enough. Thank you much.

Tony M

I thought you wanted mm but I see the inch indicator lines clear enough.

Have fun.

xschop

I have dial calipers

VSAT88

xschop wrote: »

Looking good. Were you able to measure one of the magnet mount plates diameter?

I'm saving two of the next RD0 plate batch for the SL2K-V2 magnets and pair of new domes I still have.

Looking REAL good !

VSAT88

Tony M wrote: »

well...

I got antsy and went to do the other 6 tweeters last night. Started at around 11PM and finished at 4AM. I still have at least one old one left. There maybe a couple more in the back room.

I had a blast but my back and neck told me I over did it. I knew what to do, had the tools out already but carving into the back of the face plates was harder. I believe the plastic was a harder composition on most of these compared to a couple of others. I noticed in one of the pics, the plate mounting hole backs are different. That has to be why I had a tougher time carving. But still, it was rewarding and time flew by fast.

Here's a few picks;
















Now ready for testing in the future...

Those are looking great Tony. Silk Dome, like that you call them that. I label my re domed 194's xschop-vc ebay. because of all the work he did on the 194's. Keeps them straight in my head from any others I may have around here. I bought most of my Polk bolts at Fastenal . They have the biggest selection here in this area.

xschop

One caveat of modding the plastic factory bezels is the dome sets recessed more by 0.050" or so from what I wrote down.

From what I've found on doping compound search, dibutyl pthalate has been used before.

Tony M

I don't like that the eBay domes w/flanges sit lower than the originals.

I feel after filling the angle space with some kind of caulk or what-ever, it should act like a horn and maybe benefit its sound.

I knew there was something else I wanted to look for at Lowe's. black caulk in a squeeze tube style.

I made an offer to a China eBay dealer for some more of these domes. I think I'll have 8 more to do if I put these I just did into my collection of 4s and 5s. Well I guess I won't have but 4, maybe 6 to do later.

Anyway...

I've bought domes, a drill press, a new drill press vice, screws and a caliper. Oh...a set of Dremel bits.

Maybe I should've just bought new 0194s.





Then I wouldn't have had any creative fun, would I.

xschop

Let me know if you want to part with a couple of the new domes. Mine said arriving Sept 29th lol.

Most importantly you had fun, saving a boatload of funds.

I'm listening to my 5b's with the newly "home-doped" domes.....

Tony M

Yours might arrive before mine...

As for the new domes to come, the seller hasn't accepted my offer yet. I think they're still sleeping or about to get up over there in China.

I think the ad I'm looking at says the same time frame. My last order was here in about a week I think. They arrived a lot faster than that month long window I remember seeing a year ago also.

If these domes sound like the 2 I listened to the other night, that would be 60.00 x 8 for a total of 480.00 for real 0194s.

I think I'm doing good $$ wise IF these perform CLOSE to the 0194s even with buying that little Harbor Freight brand drill press off of Craig's list.

I believe my eBay domes I just used are that tight weave. I hope the next ones are too.

So you doped the domes too?

Your title "home-doped" domes reminded of that hit last year or longer by "Twenty One Pilots'..."Stressed Out" ( Good Dope Days ).

I really liked that song and then it was being played in every place I went it seemed. I still like the beat.

xschop

I'll share my findings since this can be done with a common supplement. Back in my research days, Retinol or Retinoic acid has a very close molecular weight to dibutyl pthalate.

It's fat-soluable and importantly,
It sticks to proteins too ( silk e.g.)

It indeed does clear up frequencies and transitions in these uncoated domes. Also I took them back out after a few hours and the tight weave silks didn't allow the compound to penetrate back into the back-sides. Not sure it matters if it does. Each dome took just a couple micrograms to coat.

The sound is excellent and indeed improved...
Coated on left, uncoated right... Just brushed on with small artists brush evenly with no excess until perfect sheen achieved...

Tony M

That is some fine coating skills you've got.

I might try that later.

Well, the seller didn't want to come down at all. Why did they put "make an offer" on their ad?

I asked for 7.00 off of a 50.00 + 7.00 shipping ad.

Their shipping time estimate was what I thought. Sept. 8 to Oct. something. But I think it would be shorter. I looked at their rating score and saw a red flag from a year ago. They didn't ship the number that was in the ad.

I'm tired from the past few days and haven't decided what I'm going to do with this seller. I looked at others a bit ago and thought, I might still order them from this seller and hope I get the same quality. Maybe later. It's from seller: scarlettchen (1248 )

https://www.ebay.com/itm/16pcs-25-4-25-5mm-1-silk-diaphragm-dome-Tweeters-horn-Drive-voice-coil-8Ohm/122719536939?_trkparms=aid=111001&algo=REC.SEED&ao=1&asc=20160908105057&meid=76a150a7d9114e47b3293858280f9312&pid=100675&rk=1&rkt=15&mehot=none&sd=122719536939&itm=122719536939&pmt=0&noa=1&pg=2380057&brand=Unbranded&_trksid=p2380057.c100675.m4236&_trkparms=pageci:744a5784-e89d-11ea-bf0a-74dbd180f727|parentrq:31717a741740aad981776ee7ffff909e|iid:1

xschop

That's a pretty good deal. I'm not surprised there are no USA sellers.

Tony M

This afternoon I went to measure the tweeter screws thread length with adding the new dome flange's thickness. One screw hole on the magnet was shallower than the others. I noticed it the other night too.

Well...I tried to tighten the screw deeper into the hole and then "TIK". The plastic wasn't cracked...

I then thought I'd see if another screw could be tightened a little more. No sooner did I just start to tighten the second screw..."TIK" sound happened again!

I looked at the thing and noticed the dome was leaning. WTH. Did I break the glue seal on the top magnet plate? YUP.

I loosened the top plastic faceplate and thank god the new dome came right off. It looks fine.

I pulled out my one spare SL2000 I had right there and put the dome and plate on the good magnet. The screws went down pretty good into all 4 holes. So the one magnet had a shallow hole. I was just IMPATIENT.

I've ordered new 8-32 x 3/16" long button head screws to see if they will fit properly.

I'll find out in a week.

VSAT88

With the talk of doping should ferrofluid be added to the discussion ? I have cleaned out old contaminated fluid in tweeters before then put in new but nothing more than that.

audioluvr

That's a good question. How does Ferrofluid age? Is it like capacitors and needs to be replaced every 15-20 years for maximum performance? I think you're onto something!

xschop

Anything for better sound. Thats a good idea if it can be implemented.

VSAT88

I know there is a way, software, microphones and such to measure the frequency response and such as that. I have never delved into all that. It either sounds good or not to me pretty much. However, if such measurements could be made as the doping / ferrofluid is added / subtracted whatever, that would be cool. As far as ferrofluid there was none used as far as I know on any of the vintage model tweeters from P.A. Of course, that does not mean it could not be introduced. Snell speakers, both sets I have use ferrofluid in the treeter. Its kind of expensive. As far as life goes that stuff does need to be cleaned out and put in new after a while. How long would depend on temperature / how hard a speaker was driven / how long and what environment the speaker was used in I suppose. I do not think it wears out, it just get contaminated over many years and can get gummy and cause the tweeter to not respond as it should. I know that for sure because I have fixed the problem before with a Vifa tweeter in one of my Snell J III's.

xschop

IIRC, I think the SL5000s had Ferro fluid when one fell off inside the cabinet.

xschop

I just ordered 4 ea more of those full diameter tight weave domes from that seller. Gerald Albright's and Boney James' saxophones are now accurate with the application of the Vit A derivative. I was going to purchase the DBP, but I don't see a need at this point. Very happy with this mod....

VSAT88

Can see why.. Excellent work !