A Salk for tubes (not Pharos).

bigjppop · « **on:** 17 Jun 2009, 01:05 am »

I've become quite enthralled with the Salk line of speakers but at heart I'm a tube guy. I know Salk produces the Pharos speaker to match with tubes, but that is just a little too big for me (size and prize).

Being very much a rookie when it comes to things like why do speakers work they way the work, I'd love to hear peoples opinions on if it would even be possible to build something like the HT1 in a fashion that would allow it to work well with a nice SET tube amp. Sensitivity would need to be somewhere in the neighborhood of 95+ db. Before I go and bother Jim, I'd like to know if this is even possible. What makes high efficiency speakers highly efficient? The drivers? The actual box? Could the HT1 simply have different drivers popped in to make it more efficient?

I know there are other manufacturers out there that build what I'm looking for, but I love the Salk business model, LOVE the look of what he builds, and almost love the sound. I've only heard the Song Towers and I'm pretty sure that the things that I didn't totally fall in love with (a little sharp/bright/harsh/analytical/pick your word) could be alleviated by some tube amplification. Mind you, I said A LITTLE in my qualification. Overall I enjoyed the sound, but like I said, at heart I'm a tube guy.

Anyway, I'd love to hear some thoughts.

Nuance · « **Reply #1 on:** 17 Jun 2009, 01:20 am »

I know you don't want to "bother" Jim, but he and Dennis are really the only two that could definitively answer your question. If neither responds by end of day tomorrow, I say give Jim a call. He's the man, and he'll be straight with you.

JoshK · « **Reply #2 on:** 17 Jun 2009, 01:23 am »

If you want higher efficiency and smallish size that by laws of physics means a lot less bass. Its called Hoffman's iron law. In order to get the same bass response as lower efficiency speakers, higher efficiency speakers need to be much larger.

DMurphy · « **Reply #3 on:** 17 Jun 2009, 01:40 am »

Quote from: JoshK on 17 Jun 2009, 01:23 am

If you want higher efficiency and smallish size that by laws of physics means a lot less bass. Its called Hoffman's iron law. In order to get the same bass response as lower efficiency speakers, higher efficiency speakers need to be much larger.

I'm afraid that's a fact. Which is another advantage of active desktops. I think I'll bow out at this point. I think most SET's are distortion machines, and I just can't see designing a speaker that's designed to work well with gobs of harmonic distortion and an uneven frequency response.

TomW16 · « **Reply #4 on:** 17 Jun 2009, 01:49 am »

Quote from: DMurphy on 17 Jun 2009, 01:40 am

Quote from: JoshK on 17 Jun 2009, 01:23 am
If you want higher efficiency and smallish size that by laws of physics means a lot less bass. Its called Hoffman's iron law. In order to get the same bass response as lower efficiency speakers, higher efficiency speakers need to be much larger.

I'm afraid that's a fact. Which is another advantage of active desktops. I think I'll bow out at this point. I think most SET's are distortion machines, and I just can't see designing a speaker that's designed to work well with gobs of harmonic distortion and an uneven frequency response.

Not a SET man Dennis?

DMurphy · « **Reply #5 on:** 17 Jun 2009, 02:06 am »

Quote from: TomW16 on 17 Jun 2009, 01:49 am

Quote from: DMurphy on 17 Jun 2009, 01:40 am
Quote from: JoshK on 17 Jun 2009, 01:23 am
If you want higher efficiency and smallish size that by laws of physics means a lot less bass. Its called Hoffman's iron law. In order to get the same bass response as lower efficiency speakers, higher efficiency speakers need to be much larger.

I'm afraid that's a fact. Which is another advantage of active desktops. I think I'll bow out at this point. I think most SET's are distortion machines, and I just can't see designing a speaker that's designed to work well with gobs of harmonic distortion and an uneven frequency response.

Not a SET man Dennis?

Well--actually--I did hear one that I thought was pretty good for an underpowered amplifier. So I guess they're not inherently bad.

funkmonkey · « **Reply #6 on:** 17 Jun 2009, 02:26 am »

Not really small in form factor but check out the Archos. I believe they were designed with efficiency in mind and to pair up with tube amps. You would have to ask Jim but perhaps he could adapt something from that design to suit you. It does share the same ribbon as the HT1. Again, Jim would be the guy to talk to about this...

bigjppop · « **Reply #7 on:** 17 Jun 2009, 04:38 am »

So not much love for the SET in the Salk Circle...

I must say I'm a little surprised. It seems that for those of us afflicted with auphiophilia to the extent that we would hunt down a small custom speaker manufacturer in Michigan, the SET world would be right up our alley. Is it just me? aa

I really like the form/size of the HT1 and was hoping to be able to do something stand mounted (I could always experiment with a nice musical sub) but maybe the laws of physics are just not going to cooperate.

Anyone else have any other thoughts?

Big Red Machine · « **Reply #8 on:** 17 Jun 2009, 11:57 am »

Are you talking in the neighborhood of 8 watts? If you were at 40+ watts you'd be able to drive just about every speaker offered to decent levels.

bigjppop · « **Reply #9 on:** 17 Jun 2009, 12:13 pm »

Quote from: Big Red Machine on 17 Jun 2009, 11:57 am

Are you talking in the neighborhood of 8 watts? If you were at 40+ watts you'd be able to drive just about every speaker offered to decent levels.

I've got my eye on a couple of different amps that are between 6-9 watts per channel so I'm pretty sure I'd need something in the 94+db range. I have yet to find any supper efficient speakers that I love so I may just have to bite the bullet and go with a push-pull design that's more in the neighborhood of 40-60 watts per channel. I don't typically "bring the house down" with my volume levels and I don't have any issues with using a nice sub so... we'll see.

Miney · « **Reply #10 on:** 17 Jun 2009, 12:41 pm »

Good question - been wondering myself. Jim Salk probably has some good insight here, considering there's a Salk Sound website page offering "both stock and modded Jolida tube amplifiers."

If you do call Jim can you post an update? Thx.

JoshK · « **Reply #11 on:** 17 Jun 2009, 02:38 pm »

A standmount speaker the size of the HT1 with 95db/w sensitivity would be lucky to have a -3db down point at 300hz. I don't mean to rain on your hopes, I own a SE amp too. But these are just the facts.

DMurphy · « **Reply #12 on:** 17 Jun 2009, 04:40 pm »

Quote from: JoshK on 17 Jun 2009, 02:38 pm

A standmount speaker the size of the HT1 with 95db/w sensitivity would be lucky to have a -3db down point at 300hz. I don't mean to rain on your hopes, I own a SE amp too. But these are just the facts.

You can gain some sensitivity by doubling up on the woofs, but that increases size and lowers the impedance, which I doubt SET's are thrilled about.

turkey · « **Reply #13 on:** 17 Jun 2009, 06:08 pm »

Quote from: bigjppop on 17 Jun 2009, 04:38 am

So not much love for the SET in the Salk Circle... I must say I'm a little surprised. It seems that for those of us afflicted with auphiophilia to the extent that we would hunt down a small custom speaker manufacturer in Michigan, the SET world would be right up our alley. Is it just me? aa

It certainly isn't me.

Jim's speakers seem to be very refined mainstream designs. They might well work ok with a given SET amp, but I bet they'd work a heck of a lot better with a more normal amp that isn't so limited.

I could very well see someone looking at the speakers on the market and then choosing speakers from Jim. I cannot understand why anyone would head down the SET path.

oneinthepipe · « **Reply #14 on:** 17 Jun 2009, 06:16 pm »

I understand the advised approach is to decide on speakers, then select an amplifier to drive the speakers, rather than deciding on an amplifier and then be limited to speakers that the particular amplifier is capable of driving. There are some very fine higher wattage tube amplifiers available, and a decision to use tube amplification should not be an obstacle to purchasing speakers.

chrismercurio · « **Reply #15 on:** 17 Jun 2009, 06:49 pm »

Quote from: JoshK on 17 Jun 2009, 02:38 pm

A standmount speaker the size of the HT1 with 95db/w sensitivity would be lucky to have a -3db down point at 300hz. I don't mean to rain on your hopes, I own a SE amp too. But these are just the facts.

JoshK is right. Maybe one of those little Fostex fullrangers or a Lowther...but Hoffman's Iron Law demands its own attention. There is a reason speakers that offer both efficiency and extension are BIG. Best of luck...but realistically if you are looking for extension into the 40-60hz range in the 94+db range you are looking at a couple of cubic feet minimum.

This is one of those areas that engineers don't try to cheat physics, (except in sub's)

Chris

p.s. There are some things you can buy/build/have Jim Salk build for you, but as this is the Salk forum, not a diy forum, I'm going to pass on that.

DMurphy · « **Reply #16 on:** 17 Jun 2009, 07:44 pm »

Quote from: oneinthepipe on 17 Jun 2009, 06:16 pm

I understand the advised approach is to decide on speakers, then select an amplifier to drive the speakers, rather than deciding on an amplifier and then be limited to speakers that the particular amplifier is capable of driving. There are some very fine higher wattage tube amplifiers available, and a decision to use tube amplification should not be an obstacle to purchasing speakers.

Right--and Frank has some excellent tube or tube hybrid
equipment. My concerns only go to the SET thing.

bigjppop · « **Reply #17 on:** 17 Jun 2009, 09:03 pm »

Well it appears that I'm chasing the rainbow here. It looks like if I want to go Salk I'll be looking at a push-pull tube design.

Thanks for all the input!

Jeremy

chrismercurio · « **Reply #18 on:** 17 Jun 2009, 09:05 pm »

Well,

There are SET amplifiers that use big tubes like the 211, 845, and GM70 that provide copious amounts of power and work well with loudspeakers of average efficiency.

Good luck regardless of what you decide to do,

Chris

Jeff B. · « **Reply #19 on:** 18 Jun 2009, 02:15 am »

Being the designer of the Pharos and Archos, both of which are higher efficiency designs, maybe I should comment.

First, what makes a speaker efficient is primarily in the driver design itself. But there are always trade-offs - and those trade between Fs, Vas, and Qes, which are driver parameters. In other words, they lock you into what is called Hoffman's Iron Law, which basically tells us that you can not have high efficiency, low bass, and a small box at the same time. One of those has to go in order for the other two to exist. When we targeted a high efficiency design we had to set a target for each of these. In the Pharos I targeted 95dB sensitivity. Then I had to compromise between acceptable low bass extension and enclosure size. The JBL woofer allowed me to hit the sensitivity mark and get 40Hz extension out of a reasonably sized box at the same time. It offered the best compromise available at the time.

For the Archos, the newly redesigned Lambda woofer gave us lower bass extension in a smaller box, and we kept the sensitivity close to that of the Pharos, but it is a little lower.

Then there is the matter of the impedance. This is tricky. It is not easy to design a three-way speaker with flat response and flat resistive impedance at the same time. However, this goal was accomplished with the Pharos. The impedance curve with it is nearly a flat line above the bass peaks (above 100Hz).This makes the Pharos a perfect match for the most demanding SET amps. The Archos has a fairly well-controlled impedance that varies only from a low of about 5 ohms to a high of 9 ohms across this same range. In most cases this is stable enough that most any amp will be fine with it too, but it is not quite as flat (resistive) as the Pharos impedance is.

The Pharos also has an extremely flat frequency response as well. Apart from not having really deep bass extension it does everything else extremely well. The Archos, by virtue of the open baffle midrange, is a little more dependent on the room set-up and placement, but can also offer very flat response when set-up well. I have listened to both, but I probably should keep my personal opinions on which I would pick to myself.

What I am getting at is - you can ask us to design you a high efficiency speaker with great bass response that comes in a reasonably small box, and unfortunately, it just can't be done. Something has to give somewhere in one of those requirements. As a result we have tried to offer what we felt was the best and most widely appreciated combination of those characteristics in the speakers that were offered. We felt that what we had arrived at would have the widest possible appeal - compared to a refrigerator sized speaker or one that only reached down to 70Hz before it started rolling off.

I'll tell you this; if Jim were located in Japan he would be selling Pharos' like crazy. Both this JBL woofer and the PHL midrange has a cult following over there, and they love ribbon tweeters too. This speaker would have some real impact in that market. Also, beware of some commercial speakers that advertise high sensitivity and low bass. A lot of tests show that many of these do not measure up to their claims in either category. We have tried to be conservative in our ratings so that everything was out there on the table and lived up to the claims made.

Jeff B.