[jsalk]

As most of you following this circle know, we have been working on a new flagship speaker design for about two years now.  We finished the first prototype pair and showed them at AKFest last week-end.  As with all new designs, finishing them is one thing and fine-tuning them is another.  We are currently in the process of fine tuning the design and hope to release it in the next couple of weeks.

I have spent a good deal of time in the last week listening and Dennis Murphy and I have talked about a number of very small tweaks we would like to make.  But overall, we are VERY pleased with the design and feel we have met or exceeded all of our goals.

Since we will be releasing this design very soon, we need a name.  Since it really has no drivers in common with our Veracity series speakers, we don't feel HT4 is a viable candidate where names are concerned.

For those who perhaps have not seen the design, here are some pictures of the first cabinets produced for one of four versions we will be offering.  These were built with a 12" woofer section and constructed from solid bamboo.



A closer shot...



A side view of the top...



And a rear view of the top...



Details in the next post...

- Jim

[jsalk]

Before I get into the specifics, I would like to personally thank everyone who contributed to the design.

First, this design would not be possible without the total dedication of Dennis Murphy.  Dennis has spent countless hours over the past two years testing a myriad of potential design concepts and drivers. And, naturally, his crossover design pulls all the elements, finally selected, together in a totally seamless fashion.

But there were a great number of other individuals whose contributions made this design possible and I do want to take a moment to give them their due.

Paul Kittiner contributed a great deal to the design of the woofer section.  He used Martin King's formulas to develop a transmission line cabinet design for the woofer section.  Although, in the end, we adopted a different approach, none-the-less his input was invaluable in reaching our final goal.  The woofer section we finally adopted was designed by Jeff Bagby.  Jeff is the author of numerous software programs for speaker design and his dual passive radiator design was just what we needed to make this particular design work.

As you can imagine, the cabinet was quite a challenge.  Mike Vettraino worked with me on getting a SolidWorks CAD model drawn up.  Tom Boyer worked with our drawings to CNC route all the initial cabinet blanks.  And Solid Concepts did the final CNC milling on the cabinet tops to turn Mike's drawings into finished enclosures.

Of course, none of this would have been possible without the great work of our fine staff.  With all the other speakers we were building at the time, these people pulled out all the stops to fit this project into our busy schedule.  John Fallows brought a great many ideas to the table.  Ammar Dabesh and Juan Luis spent hours gluing up the laminated cabinet sections.  Sam Zeoli wore himself out with the belt sander preparing the cabinets for finishing.  And Teresa Allen did her always excellent job finish sanding in preparation for the final topcoat.

This was a huge task for a small company such as ours and there were countless others who contributed to the project's success.

I would like to take this opportunity to thank them all personally for their contributions.  Without them, this speaker would never have been born.

More details in the next post...

- Jim

[JoshK]

Sphinx

[ebag4]

Beautiful speaker Jim. The name that jumps out at me is "The Capitol"

Best,
Ed

[jsalk]

Before we get into the design specifics, here are a few graphs that may be of interest...

On axis frequency response...



15 degrees off-axis...



30 degrees off axis...



Notice the similarities?  Measurements up to about 80 degrees do not look much different.  When walking around the room at AKFeset last week-end, I was struck by the fact that no matter where you were in the room, the speakers sounded about the same.  Sure, bass response will boviously be different in different parts of a given room, but there seemed to be no change in sound from the upper bass regions on up.  I have never heard a speaker do this before.

Here is an impedance graph...



More in the next post...

- Jim

[groovybassist]

Salk "Sentinel" is what hits me over the head when visually looking at the design.  Stunning Jim!

-Mike

[rahimlee54]

Man those off axis frequency responses are great, I hope to hear them someday.

[jsalk]

OK...now on to some specifics.

First, let me say that, from the onset, this design was all about performance and at no time did we make compromises in order to control the price of the finished speaker.  As it turned out, everything about this speaker turned out to be expensive.

Let's start with the drivers.

The tweeter is a custom RAAL tweeter from Serbia.  In talking with Aleksander, we were able to come up with a tweeter that had multiple taps the resulted in three levels of sensitivity.  This allows us to offer three tweeter levels with absolutely no change in the basic tweeter crossover.  In the production prototype we showed at AKFest, we had a flat setting along with a 1 1/2db boost and cut.  At the show, we talked about this feature and decided that owners would be very unlikely to use the 1 1/2db boost.  So the decision was made to modify the crossover so that, in the final version, we would have a flat setting, a 1 1/2 db cut and a 3db cut.

This is one of the finest ribbon tweeters currently being made, and we are very happy to have been able to work with RAAL on this project.

The midrange is something very unique.  We were approached about a year ago by FAL.  They had a flat diaphragm design that looked interesting but was quite unconventional.  We had no idea at the time whether this represented a break-through in driver technology, or just another audio gimmick.  Seas, ScanSpeak and others were all coming out with new driver technologies at the time and we bought samples of all of the latest cutting-edge drivers.  When we built test cabinets, we cut baffles for all of these drivers, including the FAL.  We then listened to all of them.  There really wasn't a bad driver in the bunch.  But there was something very unique about the sound of the fall.  No matter where we went in the room, the sound emanating from the FAL driver was very coherent.  As you walked around the room, you could plainly hear changes in the frequency response of all other drivers.  Not so with the FAL.  We had kind of mentally written the FAL off initially as kind of a novelty design, but nothing to take too seriously.  But these initial listening sessions caused us to take a more serious look.  And, in the end, designs worked up with this driver did some things no other combination of drivers could do.

For the woofer, we had used TC Sounds woofers in our HT3 and really liked the results.  We wanted bass extension down to about 20Hz, so we obviously needed a larger driver than the 10" in our HT3's.  So we made arrangements to have 12" versions of the same basic driver manufactured for the woofer section.

At first, we tried a simple ported design.  But when you are producing bass this low, the air velocity at the port was high enough to dry your hair and the port noise was not acceptable.  Next, Paul Kittinger worked up a transmission line version for us.  But, alas, port noise was still a problem.  So we turned to Jeff Bagby to work up a design with passive radiators.  This would allow the extension required without any port noise.  And the decision was made to use two passive radiators so that their vibrations would cancel each other out and keep cabinet resonance to a minimum.  

Now we had the drivers and it was on to cabinet design...

- Jim

[zybar]

I would love to hear more about the four different versions...

George

[jsalk]

Early on, one of our primary design goals was to design a speaker with a very deep and wide soundstage, along with a good deal of ambiance.  This had a profound effect on cabinet design.

For example, we wanted no baffle around the tweeter.  This would allow sound emanating from the tweeter to travel as close to 360-degrees as possible.  Of course, from an aesthetic point of view, you wouldn't want the tweeter body and wiring to show.  So the tweeter enclosure had to hold the tweeter in place and then get out of the way.  Minimalistic was the word of the day.

We also wanted a midrange cabinet that was quite small so that, again, dispersion would not be hampered by a large front baffle.  And we also wanted to take advantage of the backwave of the midrange driver to provide added ambiance.  Of course, an open baffle design would allow for a great deal of ambiance.  But there are also problems involved with open baffle designs.  While they can produce a nice feeling of spaciousness where orchestral reproduction is concerned, the added ambiance has a tendency to make female vocalists sound like their mouth is 10 feet wide.  And there is a matter of cancellations in the boundary areas where the front wave and back wave intersect, causing a null in response.

By going with a long tube, you can avoid some of these boundary effects.  What's more, the user can stuff the the "tube" to varying degrees to achieve the appropriate level of ambiance for his particular room and taste.  You can even close the back entirely for a sealed response.

In order to hit the target of 20Hz, the woofer section needed to be somewhat large.  And we decided early on to use 2" thick walls and internal bracing to keep the cabinet resonances to an absolute minimum.  Opposing passive radiators would not only eliminate any possibility of port noise, but since they would be moving in opposite directions, their vibrations would cancel out as well.

So this left us with a considerable design challenge.  We had a large "box" for the woofer section, a small "box" for the midrange and almost no "box" for the tweeter.  When we stacked these boxes up, it made a very un-appealing visual statement.  

So we began working up a series of CAD drawings to see what we could do to deal with the aesthetic issues we found ourselves confronted with.  

It became apparent, very early on, that we would not be able to use standard construction methods to build these enclosures.  So we decided to use a trans-lamination process.  Instead of cutting panels, we cut shapes.  The top cabinet is made from about 18 pieces of 3/4" material while the woofer section was built with about 30 laminated layers.

This lamination process allowed us to construct a cabinet with multiple compound radii and walls of any thickness desired.  It also meant we would have to use CNC routers and very labor-intensive processes to build the cabinets.

More to follow...

- Jim

[arthurs]

NC1

The no compromise one...

[Nuance]

Salk Pinnacle
Salk Revalator
Salk Phoenix
Salk Paragon
Salk Quintessence
Salk Apex
Salk Summit
Salk Apogee
Salk Vertex
Salk Zenith


Okay...out of ideas for now.  My brain hurts.   

[oneinthepipe]

I started with series names.

Salk Signature Sound Statement Series 
Salk Signature Sound Definition Series   
Salk Signature Sound Unlimited Series 
Salk Signature Sound Profundity Series
Salk Signature Sound Precision Series
Salk Signature Sound Perfection Series
Salk Signature Sound Dominion Series
Salk Signature Sound Flagship Series
Salk Signature Sound Fidelity Series
Salk Signature Sound Concert Series

Speaker name could be a model name, using an above-mentioned name, or an alpha/numeric designation, such as TL20 (because the speaker is a TL and plays down to 20hz), or a name, such as Fidelity 20, Flagship Tower or Qi Jian Tower.  Qi Jian is flagship in Chinese.  Since bamboo is often associated with China, I looked up some Chinese names, although I don't know if all the speakers will be constructed from bamboo.

For a slogan/tag line, I offer, as examples, "The Salk Signature Sound Statement Series TL 20 redefines the ambit of speaker performance" or "The Salk Signature Sound Dominion Series TL 20 redefines the ambit of speaker response."

[oldmp3]

Fantastic speakers.  I had the opportunity to hear the prototypes at Dennis Murphy's.

Congratulations Jim, Dennis, and the entire team!

How about Salk Serenity, Serenade, or Symphony?

[zybar]

Here are a few possibilities:

Salk Promontory (a prominent mass of land overlooking or projecting into a lowland or  a bodily prominence)

Salk Supernal (being or coming from on high or located in or belonging to the sky)

Salk Ethereal (of or relating to the regions beyond the earth or marked by unusual delicacy or refinement)


George

[DMurphy]

Great write up, Jim.   Just one minor correction.  The frequency response plots aren't quite labeled right.   The on-axis is the bottom one, and if you place that one on top, they'll follow in the correct order.  As for a name, based on sound and not looks, the most apt would probably be The Orchestra Hall. 

[funkmonkey]

So as I was wracking my brain to come up with an original name, I checked thesaurus.com for synonyms of the word sound.  The most significant ones in italics:

Definition:   complete, healthy
Synonyms:  alive and kicking, effectual, entire, firm, fit, flawless, hale, hearty, in the pink, intact, perfect, right, right as rain, robust, safe, sane, solid, stable, sturdy, substantial, thorough, total, unblemished, undamaged, undecayed, unhurt, unimpaired, uninjured, up to snuff, vibrant, vigorous, vital, well, well-constructed, whole, wholesome, wrapped tight

Definition:   logical, reasonable
Synonyms:    accurate, advisable, all there, cogent, commonsensical, consequent, convincing, cool*, correct, deep, exact, fair, faultless, flawless, got it together, impeccable, intellectual, judicious, just, levelheaded, orthodox, precise, profound, proper, prudent, rational, reliable, responsible, right, right-minded, right-thinking, satisfactory, satisfying, sensible, sober, solid, telling, thoughtful, together*, true, trustworthy, valid, well-advised, well-founded, well-grounded, wise

Definition:   accepted, established
Synonyms:    all there, authoritative, canonical, dependable, fair, faithful, fly*, go*, hanging together, holding together, holding up, holding up in wash, holding water, kosher*, legal, legit, loyal, orthodox, proper, proven, received, recognized, reliable, reputable, safe, sanctioned, secure, significant, solid, solvent, stable, standing up, tried-and-true*, true, valid, washing

Definition:   something heard or audible(all of these would obviously apply)
Synonyms:    accent, din, harmony, intonation, loudness, melody, modulation, music, noise, note, pitch, racket, report, resonance, reverberation, ringing, softness, sonance, sonancy, sonority, sonorousness, static, tenor, tonality, tone, vibration, voice

Definition:   produce noise(yep, they do all of these too)
Synonyms:    babble, bang, bark, blare, blow, boom, burst, buzz, cackle, chatter, clack, clang, clank, clap, clatter, clink, crash, creak, detonate, echo, emit, explode, hum, jabber, jangle, jar, moan, murmur, patter, play, rattle, reflect, resonate, resound, reverberate, ring, roar, rumble, shout, shriek, shrill, sing, slam, smash, snort, squawk, thud, thump, thunder, toot, trumpet, vibrate, whine, whisper


So many of the synonyms (and each definition) seemed to apply to this speaker that I nominate simply:
Salk - Sound 1

[jbtrio]

Hi Jim,

 Can you tell us what Caps are being used in the crossovers?

Posted the question last week, maybe you missed it.
Curious if you're using something different then Sonicaps and Solens.

Regards,

Joe

[jhm731]

RFDP-1

R=RAAL ribbon tweeter
F=FAL flat midrange
DP= Dual Passive radiators

[bzaggie]

salk fidelity series

definitions:

   1.  Faithfulness to obligations, duties, or observances.
   2. Exact correspondence with fact or with a given quality, condition, or event; accuracy.
   3. The degree to which an electronic system accurately reproduces the sound or image of its input signal.