Ron's SongTower-like design in dyed crotch mahogany

jsalk · « **on:** 15 Jun 2011, 09:43 pm »

Ron wanted a pair of SongTower-like speakers but really wanted to "roll his own," so to speak. He chose some nice Seas woofers and a Fountek ribbon tweeter. He then developed a transmission line cabinet for the woofers and we built a test cabinet. Once that was complete, Dennis worked his magic to bring all the elements together.

The cabinets are essentially the same as the SongTower cabinets but 2 1/2" deeper.

Ron selected some veneer and had it sent to us. We took it from there. Here are the results...

I have no idea why photos always look better on my computer than here on audiocircle. The photos certainly do not do justice to this pair. At any rate, here's a close-up...

Happy listening Ron!

- Jim

Tone Depth · « **Reply #1 on:** 15 Jun 2011, 10:54 pm »

Wow, Jim, you really redefine "Custom built."

SlushPuppy · « **Reply #2 on:** 15 Jun 2011, 11:52 pm »

Elegant.

eclein · « **Reply #3 on:** 16 Jun 2011, 12:15 am »

Jim how do they sound with the Fountek tweeter????. I'm looking at a similar build....very nice, very, very nice.....

...and what was the thoughts behind setting the tweeter slightly to one side and not centered in the baffle between the woofers.

jsalk · « **Reply #4 on:** 16 Jun 2011, 12:52 am »

Quote from: eclein on 16 Jun 2011, 12:15 am

Jim how do they sound with the Fountek tweeter????. I'm looking at a similar build....very nice, very, very nice.....

...and what was the thoughts behind setting the tweeter slightly to one side and not centered in the baffle between the woofers.

The Fountek tweeter sounds much like the AC G2 and LCY 110. It is a very nice tweeter.

As for the tweeter position, it is for diffraction control. Centering the tweeter would certainly be easier since the same template can be used for both speakers. But it is not ideal.

Keeping the analysis simple, if you center the tweeter, the distance to each side of the cabinet is the same and sound at a specific wavelength will hit both sides at the same time, creating diffraction artifacts in the process (think of turbulence at the edge of a wing). You still get diffraction artifacts if you move the tweeter off center, but those artifacts occur at two different frequencies rather than one and the effect is cut in half. So you get two smaller sets of artifacts rather than a single larger one. The result is response that is a little smoother.

- Jim

PMAT · « **Reply #5 on:** 16 Jun 2011, 01:12 am »

I LOVE crotch mahogany. I love saying it too. I'm going to name my next cat Crotch Mahogany.

Bill Baker · « **Reply #6 on:** 16 Jun 2011, 01:21 am »

As always Jim, very nice work. I think going with the Fountek tweeter is a good choice as they are very good units.

eclein · « **Reply #7 on:** 16 Jun 2011, 01:22 am »

Thanks Jim!!!! I totally understood that....I'm starting to get this whole thing...LOL...I'm going to get the Fountek 2 way kit from Madisound and it uses that tweeter so I'm very happy you think they sound good...phew!!!

They are one of your finest looking speakers I've seen you do over the time I've been hanging out here....beautiful!!!!!

Nuance · « **Reply #8 on:** 16 Jun 2011, 03:49 am »

Quote from: PMAT on 16 Jun 2011, 01:12 am

I LOVE crotch mahogany. I love saying it too. I'm going to name my next cat Crotch Mahogany.

LOL - that's the funniest thing I've heard all day! Thanks for that.

Ron - those look great man; love that veneer. Welcome to the Salk family!

rlee8394 · « **Reply #9 on:** 16 Jun 2011, 04:31 am »

Thanks everyone for the kind words on my new speakers. They would not have been possible if not for the wonderful support and suggestions from both Jim and Dennis. Jim did an excellent job on the veneer finish. I told him what I was looking for, and he asked if I would trust him and his crew. If he ever makes that offer to any of you, just do it and put your trust in them. They seem to have an uncanny ability to translate what it is you want into a work of art that won't disappoint!!

Dennis recommended the Fountek tweeter and I'm quite happy with it as I am with his crossover design. Dennis also redesigned the crossover networks for my B&W 601S3 speakers. His talent cannot be faulted as far as I'm concerned. I appreciate Dennis' hospitality in inviting me over to his place for the design phase and sound test. I've only listened to the prototype in the test cabinet in my system, so I'm quite excited to hear how the pair sound. I hope to one day make it out to Jim's operation in Michigan for a visit. If any of you get the opportunity to go to the Capital Audiofest, you should make every effort. There you'll meet Jim, Dennis, hear some AVA electronics driving Jim and Dennis' speakers, as well as meet a few of us ACers.

Hope to see some of you there.

Thanks,
Ron

sarge_in · « **Reply #10 on:** 16 Jun 2011, 05:37 am »

Wow...that's one amazing veneer! One of my favorites!

(W)KRP · « **Reply #11 on:** 16 Jun 2011, 05:45 am »

Quote from: jsalk on 16 Jun 2011, 12:52 am

Keeping the analysis simple, if you center the tweeter, the distance to each side of the cabinet is the same and sound at a specific wavelength will hit both sides at the same time, creating diffraction artifacts in the process (think of turbulence at the edge of a wing). You still get diffraction artifacts if you move the tweeter off center, but those artifacts occur at two different frequencies rather than one and the effect is cut in half. So you get two smaller sets of artifacts rather than a single larger one. The result is response that is a little smoother.

Would you be able to modify the inside of the cabinet, perhaps adding thickness to one side near the tweeter, to achieve the same effect and keep the tweeter centered?

pardales · « **Reply #12 on:** 16 Jun 2011, 10:30 am »

Beautiful.......again!

Kinger · « **Reply #13 on:** 16 Jun 2011, 11:36 am »

Those are some great looking speakers. Congratulations!

Just curious, how does this version of the SongTower compare to the standard in terms of frequency response with the different drivers and deeper cabinet?

jsalk · « **Reply #14 on:** 16 Jun 2011, 11:51 am »

Quote from: (W)KRP on 16 Jun 2011, 05:45 am

Would you be able to modify the inside of the cabinet, perhaps adding thickness to one side near the tweeter, to achieve the same effect and keep the tweeter centered?

If I am understanding the question correctly, the answer is no. Diffraction artifacts result any time sound hits the edge of the cabinet. Sound always tries to travel in every direction. Very short wavelengths (very high frequencies) can't because the sound hits the front of the baffle and is reflected toward the listening position. That is why there is minimal high treble behind the speaker. Longer wavelengths pass right by the cabinet edges and can travel around to the rear of the speaker. But sound at a certain wavelength that is equal to the distance from the tweeter to the cabinet edge, will hit that edge and turbulence results. This is a diffraction artifact and you can usually see it in frequency response measurements. By moving the tweeter off center, you essentially create two different center to edge distances. So there will now be diffraction artifacts at two different frequencies. But sine they no longer reinforce one another, the amplitude of each is 1/2 of what they would have been if they were both at the same frequency.

So adding material to one side of the inside of the cabinet will have no impact since the distance from the center of the tweeter to the cabinet edge will not change.

I hope that made sense.

All that said, there is some debate as to how audible all of this is. There are those who feel it makes little practical difference. But in most cases, we tend to offset tweeters. While it may not make a huge difference, it certainly can't hurt and it does help to some degree.

- Jim

ebag4 · « **Reply #15 on:** 16 Jun 2011, 12:28 pm »

Just incredilble!

That is my favorite veneer from this point forward, beautiful work.

Best,
Ed

vermont99 · « **Reply #16 on:** 16 Jun 2011, 02:17 pm »

They look fantastic!! Enjoy

rahimlee54 · « **Reply #17 on:** 16 Jun 2011, 02:37 pm »

Ron

How would you say those drivers compare to the HT2s or standard ST, I know you have listened to Jim's speakers for a while and would like your opinion.

ArthurDent · « **Reply #18 on:** 16 Jun 2011, 02:42 pm »

Congrats Ron, obviously a lot of thought and work went into their creation on your part as well. The veneer, simply exquisite.

Jim, Dennis, above and beyond as always.

Saturn94 · « **Reply #19 on:** 17 Jun 2011, 03:08 am »

Quote from: PMAT on 16 Jun 2011, 01:12 am

I LOVE crotch mahogany. I love saying it too. I'm going to name my next cat Crotch Mahogany.

Keeping on topic, beautiful speakers Ron. Looking forward to your impressions.