Silverline SR17.5 crossover modifications?

I have a pair of 17.5's that I acquired this past December. I had been building my system around a pair of Merlin TSM-SE speakers, but when I brought the Siverlines home and did a side-by-side comparison, it was no contest and I moved to the Silverlines. The stock speakers were so good that after listening to them for a while, and hearing how well they handled everything I threw at them, they just made me chuckle.

After having them for a couple of weeks I replaced the capacitors with Mundorf silver/gold/oil. I replaced the resistor with Mundorf Supreme resistors. I did not replace the inductor. The value for the capacitor is 3.3microfarads. The resistor was 2-ohms. The Mundorf Supreme resistor does not come in 2-ohms, so I used two 1-ohm resistors in series.

Also, there is not enough room on the board as-is in the speaker to accommodate the big Mundorf capacitor. So, I went to the hardware store and got a sheet of MDF and made a little mounting platform that spans two of the binding posts and mounted the capacitor to it. Also, I used Kimber Kable TCX to make any additional connections required.

If you send me an email I'll send you a picture of what I did.

Where before we all thought the speakers sounded great (several of the guys from the shop have heard the before and after), now the sound has been described as "addictive." The depth of the sound, the leading edge of notes, the decay, the liquidity (I guess I'd call it a very fast liquid!)... I'm a very happy camper! The caps needed about 50 hours before they started to settle in. I'd guess that they have a few hundred hours on them now. Every couple of weeks the guys who own the shop come by my house to listen to some tunes and have a few drinks after we've gone out to dinner. Where I hear the system more continuously, they hear it every few weeks and are each time struck by how it's settling in and just getting better and better.

Also, I had been wondering about the Mundorf silver/oil and asked the technician where I bought them how they compared to the silver/gold/oil. He said that (1) the s/o was more colored, and (2) the s/g/o was more transparent. I got the capacitors from a place in Wisconsin. However, they don't sell the Mundorf resistors, so I got them from a place in Canada.

I don't have any experience with the Duelands, but from what I read in the comparison on humble homemade hifi capacitor test web page, if I had a chance to compare the two I may have leaned toward the depth of the s/g/o. But for me the point is moot: I am very happy with the s/g/o and am not looking for anything else.

Also, you asked about silver wiring. As I mentioned before, I went with Kimber TCX for the crossover tinkering I did. It is made of their highest purity copper. They call it "hyper-pure." I refer to is simply as their "TC-grade" because it is what is in their TC line of speaker cables. I have their PR cables on my home theater. I've never hooked them up to my audio system. In the audio system the speaker cables I've auditioned:

Kimber 8VS
Kimber 8TC
Kimber 12TC
Kimber Monocle-X (hybrid using VS and TC copper)
Kimber Select KS-3033 (all TC copper)
Kimber Select KS-3035 (a hybrid cable using one strand of their hyper-pure (Black Pearl) silver and two strands of their hyper-pure (TC) copper – and the speaker cable I bought)
Cardas Cross
Audio Magic Sorcerer (all silver – and I was auditioning an older vintage of the model - a lot of silver!)
Another Audio Magic cable, the model of which I don't recall

To me the VS copper sounded a little grainier compared to the TC copper. To me the TC copper is as grainless as I can imagine. Based on that, I didn't hesitate to use the TCX wire in my crossover modification. If I had been considering silver, I suppose like everything else in my system, I would have ended up with Kimber, but that’s not to say that the Audio Magic wire isn’t great. It is really is. But for my system my instincts were to stay with all copper (except for the hybrid KS3035’s). I also was not inclined to do any auditioning of wire for this application. I know I like the TC copper from my speaker cable auditions; the TCX is what the guys at the shop use when they rework crossovers and they have a bunch of it, so I got about a foot of it, installed it and haven’t looked back.

But, I want to add that everything is system dependent. My system:

Rogue 99-Magnum preamp with NOS RCA 5692 tubes
Rogue M180 monoblocks with NOS RCA 5751 in the 12AX7 position, and NOS RCA 12AU7’s
Kimber Select interconnects and the KS3035 speaker cable I mentioned above.

I mounted the 17.5’s on Sound Anchors that I had made. Also, Ed Soler is a local to our shop and made me some really nice Soler points for the Sound Anchors. The Soler points I got are 2” diameter at the top, so the Sound Anchor folks moved the holes for the spikes inward ¼” to accommodate the big spikes. The speakers, stand and Soler points ended up weighing about 100lbs each.
Anyway, please send me an email and I’ll be happy to send you a picture of the modified crossover.

Pmboyd,

I posted my reply before reading the entire thread, and particularly your post where you said you had changed your mind, so please don't take any offense at the fact that I posted after you said the issue for you was settled. I would, however, like to add a few other comments regarding my thought process on this subject.

(1) The 17.5 crossover would be simple thing to put back as it was originally, so I decided to take the chance.

(2) I really liked the sound of the stock 17.5s but wanted to see what would happen if I tinkered with the crossover. To me it took the speaker to an entirely different level and I am very happy.

(3) The 17.5 was a $3500 speaker. The pair of Mundorf s/g/o capacitors was a little over $300, and the Mundorf resistors were about $13 each if I recall correctly. I don't know how much the Jie-Deng capacitor that Alan used originally in the speaker cost, but from looking at it I doubt it was too expensive. I'd guess the 2-ohm, 5watt capacity cement resistor probably didn't cost much more than quarter.

Now, from what I have read, Alan Yun is a one-man operation, so this factor may not apply, but if one assumes a 5x or 7x factor for the cost of parts to the final retail price, my little crossover modification might have shown up as about $1700 to $2400 of the final speaker retail price. There is certainly no way that Alan could hit his $3500 price target and use components like the Mundorf stuff I put in. That is, assuming that was his target.

Also, in his review of the 17.5's, Marty DeWulf makes the point that Alan uses really good drivers and operates them within their comfort zone. I respect Alan's genius and that is why I didn't change the crossover component values from what he used.

(4) The speaker house brand at my small local shop is Canton. The guys at the shop now describe my 17.5's as being ballsy like the Canton Karats, but having the mids and upper end characteristics of the Canton Vento Reference series. And as far as I'm concerned, that is a great combination.

But the thing I want to reemphasize is that the change I made worked in my system, and I was willing to take the chance and have the patience to let the caps start to break in before forming any conclusion.

And don't get me wrong, I loved the 17.5s as they were, but the changes I made have taken the 17.5’s to a totally different level. I love the liquidity, neutrality, speed, and transparency the s/g/o provides. The leading edge attack and decay of transients is phenomenal, and we are all hearing deeper into the music than ever before.

I would love to get a pair of the 17 Supreme (or Bolero Supreme) speakers with the 330D tweeter... and maybe someday I'll be able to... but if I did, the first thing I'd do is have a look in the back to see what values Alan used in the crossover, and I'd be on the phone ordering my Mundorf stuff.

The pair of 17.5s I have actually used to be owned by Marty's wife. I think he usually uses a Pass X350.5 for his reviews, and I don't know on what system they were played the speakers after his review... or if he used the Pass for his review. All I know is that he loved them. I also know that his partner generally does the tube equipment reviews and he loved the 17.5s, so while I'll add the requisite caveat that the changes I made worked for my tube system, I suspect that the changes would sound good in a solid-state system. You can read their Bound for Sound reviews via the link from the Silverline website.

But, finally, again, the Mundorf s/g/o is very transparent. If your system or source is crap, they are going to jump right up and tell you. But if you have your system dialed-in, then I believe you will be rewarded as I was.

Reynold853, Thanks, that was just the sort of response I was hoping to get -- practical, not theoretical, detailed and specific. The crossover upgrade consideration is back on!

Reynolds853, YES! I would be grateful to have the photos of your crossover work. Thanks again for a great post.

I own the Bolero speakers and love them so much.

I also like Mundorf caps and wonder what Alan uses for cap brands in this speaker.

The crossover is in the bottom of the speaker and I think the bottom plate needs to be removed to check out the prts.

I can't image the speaker sounding anymore right, but now I wonder.