[JP78]

is it appropriate to bring up other manufacturers in this thread? i wouldn't mind sharing some opinions but i don't want to be in bad taste.

[dave_c]

I totally agree.  I tried to keep it relevant to the topic, but the main point of this thread is that there is a market for these speakers and I am of the opinion that a Salk would make a very fine version of one.  I only point to other manufacturers as a suggestion.  The fact that there isn't a product which Salk makes that is comparable to me makes it okay, but then this isn't my forum. 

Jim I hope this is an acceptable discussion.

[oneinthepipe]

We often discuss other manufacturers' speakers here.  We tend to prefer Salk speakers, obviously, but Jim hasn't seemed to mind the discussions.  He doesn't tolerate any bashing of other manufacturers' products, however.

[Jeff B.]

^ More info please. 

These are little monitors that I designed for myself to yield the best vocal reproduction possible in a small monitor. They aren?t really LS3/5a clones, even though they started off to be that. I compiled all of the data I could round up on the little BBC monitors, including the original BBC design papers. After studying everything I decided to build my own. However, we have learned a lot about loudspeaker design since the mid 70?s and I saw no point in going backwards, so I implemented what I felt were the best techniques that I could use. I really liked the look of the Harbeth monitors so I decided to copy that look, but that?s where most of the similarity to the original ends.

My cabinet is a little larger than the LS3/5a by about ? in. in height and width, and about two inches in depth. Mine are 8?W x 12? tall X 8.5? deep, which is still a pretty small speaker. Regarding the odd look of the front baffle ? a look that people either like or hate ? it simply emulates the Harbeth monitor?s look, which then goes back to the original LS3/5a enclosure which was made the same way with the rear mounted woofer and the screw-down baffle. My cabinet is made of solid hard-maple. In an enclosure this small it is very solid and mine is extremely well sealed. Impedance measurements show that the bass peak is very high Q indicating that there is little if any leakage from the cabinet. They are structurally very strong and these are heavy little things for no bigger than they are.

I actually built three iterations of this speaker using different drivers in each one until settling on my final design. My driver selection changed the crossover topology a lot too. In my final version I tried to stay true to the original woofer by selecting a plastic cone 5?. I went with the Aurum Cantus AC130-F1, which is a very nice little driver ? mica/carbon filled poly cone, rubber surround, cast frame, large motor,  good sensitivity, and a 5mm one-way Xmax. It?s a very beefy little 5?, and better in my opinion than most of the others I have used in this range. It also has an excellent midrange reproduction too, much better than I could get from the Dayton RS150 that I worked with in the first version. I could never get the midrange that made me shout, ?Yes! There it is!? with the RS150. I got it with this driver. It is also much beefier than Seas CA15 and other comparable drivers. The Theile/Small parameters for the woofer are quite a bit different than Aurum Cantus advertises though, but this was no problem because the measured parameters favored a small sealed box, which was what I was targeting for this design to start with.

The tweeter I picked is the Dayton RS28a. This is really an exceptional tweeter, and a real hidden gem among house brands. It is made by Usher and is identical to their proprietary top of the line Be dome tweeter, except this one has a black Aluminum dome (there appears to be some debate regarding the validity of the Be dome anyway). It has a copper sleeve in the motor and two shorting rings and has some of the lowest measured distortion of any dome tweeters out there. It sounds different too ? I think due to the very low distortion. I have a lot of tweeters here (a list of some of the best tweeters made), and this one sounds more like a ribbon on the top than it does any of the domes I have. It comes across as very clean, ?fast?, and detailed with no ?splashiness? on cymbals. I also considered that nice screen protection it has over the dome since this design may someday be used as a pro monitor, and most of them have some kind of protection here.

The advantage it has over the ribbon is its ability to be used with a very low crossover point and a shallower slope. Because this driver had such a low Fs (530Hz) and very low distortion, especially in its lower range, I decided to go with a second order acoustic crossover at 1.8kHz. The woofer?s roll-off is almost a perfect 2nd order response. The tweeter?s is a little steeper than that in order to accommodate the Z offset and bring the drivers into proper phase alignment ? which is almost perfect in the crossover region. The use of the low crossover point yields very smooth off-axis polar response not found in most speakers, so the speaker?s power response is a very smooth, and the off-axis response has no significant peaks or dips. The use of a second order acoustic crossover results in less phase shift overall, and second order acoustic crossovers have a much smoother power response in the 2-4 kHz region compared to LR4.

Where I did remain true to the original LS3/5a spec was in the frequency response. Here it almost exactly matches the BBC specification for the LS3/5a. This employs the BBC ?acoustic scaling? that allows a small speaker to be perceived as more extended than it actually is, while not sounding thick or tubby in the lower mids like many small speaker can sound. I think it works very well and everyone seems to rave regarding the midrange reproduction of this speaker. (At a recent DIY gathering that I took them to some selected them as ?Best Sound at the Show?, so I was pretty happy with that.) It was the midrange reproduction of the original LS3/5a that most reviewers raved about regarding that speaker. Many felt it established a standard for vocal reproduction that continued for many years, some feel it is still the standard.  Above this region the response is almost ruler flat the rest of the way up too, so its upper-end tonal balance sounds very flat and natural on the top end.

The speaker has a sensitivity of 84dB but also has a very easy load to drive with a minimum impedance of 8 ohms through the audio range. For near-field monitoring it has enough output to meet most anyone?s needs. Even in my large family room I can drive them loud enough to be pretty happy. I close-mic?ed it and it was -3dB right at 60Hz, which isn?t bad for a small sealed speaker, especially since it is rolling off second order below that. I probably could have gotten more genuine extension out of the bass by porting it, but I stayed with the sealed enclosure since that was a key element to the BBC monitor and makes it a little more versatile in placement. Also, vented there would probably be a midbass or upperbass emphasis that could become problematic. This speaker?s bass sounds very natural. The second order roll-off blends well with most rooms as well, and adds to the sense that it is more extended than it really is, and that its size would indicate.

I told Jim that I would give him the details if he wanted to build a pair, so if someone wants a pair give Jim a call and we can figure it out from there.

Version one used a Dayton RS150 and Seas 27TDFC tweeter in a slightly different cabinet. It later became my ?Dreydel?.

Here?s a pic of version two using some Vifa OEM drivers. It sounded good, but version three beat it in almost every way.




Here?s the final version with the Aurum Cantus woofer and the RS28 tweeter.


At aDIY gathering





Jeff

[jsalk]

Scott F -

Funny you should mention the Monsoons.  About four years ago I was thinking about a narrow and shallow speaker that would work well with plasma and LCD TV's.  Based on the sound quality of the Monsoon's, I tried to source that driver.  I followed the patents through a series of sales and bankruptcies until I found the eventual patent holder in China.  I ordered a bunch of sample drivers which I still have in a box somewhere.

But the minimum order was 1000 units and I didn't have the money to invest in that kind of inventory.  So I never proceeded with the project.  Maybe I'll pull that box out and give them another look.

As for the topic of this thread, I have been looking at some small drivers that would work well in a 93 - 94 db design.  They won't play terribly low, but my thought was to mate them with a small, high quality 10" sealed subwoofer.  The resulting system would work well for computer use and as an alternative to the above plasma TV idea (although the cabinets would be slightly deeper as required). 

I don't know what kind of demand there would be for this type of setup, but I thought it would be worth playing with for a while. Who knows...

- Jim

[Scott F.]

Hiya Jim,

Those little Monsoons really are special aren't they 

I bet you could come up with something that rivals their sound without too much trouble. You could use a little 6 1/2 DVC woofer and drive it with one of the little T amps in a vented box. Roll a fixed point passive crossover, over the top of it at say 300Hz or so.

Then you could do either the ribbons (which you could sorce from Brian at VMPS until you felt you could justify the 1000 min order) or do an open baffle extended range driver like a 2" Jordan or Tang Band.

You could use another T amp to drive the ribbons or 2"ers. both of the T amps could be housed in the little sub. It would be a three piece setup just like the Monsoons.

Might be kinda fun to prototype. Cap it off with your woodwork and you could have a hit on your hands.

Something to think about  aa

[bigjppop]

Scott F -

Funny you should mention the Monsoons.  About four years ago I was thinking about a narrow and shallow speaker that would work well with plasma and LCD TV's.  Based on the sound quality of the Monsoon's, I tried to source that driver.  I followed the patents through a series of sales and bankruptcies until I found the eventual patent holder in China.  I ordered a bunch of sample drivers which I still have in a box somewhere.

But the minimum order was 1000 units and I didn't have the money to invest in that kind of inventory.  So I never proceeded with the project.  Maybe I'll pull that box out and give them another look.

As for the topic of this thread, I have been looking at some small drivers that would work well in a 93 - 94 db design.  They won't play terribly low, but my thought was to mate them with a small, high quality 10" sealed subwoofer.  The resulting system would work well for computer use and as an alternative to the above plasma TV idea (although the cabinets would be slightly deeper as required). 

I don't know what kind of demand there would be for this type of setup, but I thought it would be worth playing with for a while. Who knows...

- Jim

I'd be very interested in this type of thing to mate with a SET amp.  I very much like the idea of a small, efficient monitor paired with a high quality sealed sub (or two).  I'd love to hear more about any progress in this area.

[JP78]

well then, if i'm in bad taste please delete.

i've recently picked up a pair of audioengine a5 speakers for desktop use from an employee promo...for under 400.00 usd these powered speakers have no right to sound as good as they should. i believe these are readily available as well, and i'm not sure they'd overlap with jim's target market. for those of us on a budget i'd strongly recommend giving them a try...they're amazing respite from wearing my senn 650's all day.

i always imagine salk speakers as more of a last-step type of solution, probably somewhere in the same  breath as dynaudio mini-monitors.

[turkey]

i always imagine salk speakers as more of a last-step type of solution, probably somewhere in the same  breath as dynaudio mini-monitors.

Last step as in top-notch?

Well, why wouldn't you want your desktop speakers to be top-notch?

[Levi]

Desktop speakers reminds me of computer speakers.  Having said that I like them small as possible as my desktop is scarce in space. 

I use Audioengine but if I really want to listen to my computer, I have a usb DAC.

[jsalk]

Jim I hope this is an acceptable discussion.

No problem.

Just for the record, it is often valuable to discuss other brands in order to provide perspective.  After all, we are all here to share ideas, explore and learn.  So I have no problem with the mention of other brands.

That said, make sure to keep it civil.  Please avoid bashing other products and, above all, be respectful of other's opinions.  Feel free to respond critically to the content of other posts (in a positive fashion), but avoid derogatory comments about the person who posted them.

If we keep things civil, everyone will benefit in the end.

- Jim

[bhm7272]

I'm very interested in Salk desktop/computer speakers as well.

I've been getting into how to get audiophile quality sound out of a computer.  You can do it with a PC or a Mac, but it's stupid simple with a mac.  Believe me, I'm a pc guy, so this is a new paradigm for me as well.  I've gotten to the point of getting a separate mac mini and usb dac and putting that on my desktop as well as my main computer under the desk.  If I just want music or to do lite computing like web surfing and email, I use the mac set up.  And it doesn't make my study hot like the pc.

Anyways, I too use the AudioEngine A5 and am pretty happy with them.  I think Jim ought to buy a set for comparison, listen to them on his desktop computer at work/home for a while, and then figure out how to make a set that sound even better.  Something about that size or smaller would be good.  I'd probably be willing to pay about a grand for 'em.  My .02 cents worth...

[turkey]

It looks to me like Jeff has already solved the problem for people who want desktop speakers. Just combine a pair of his little monitors with a subwoofer.

They've got the Archos and the Pharos, so these could be the Minimos.

For people with zero extra space on their desk, a small single-driver system would seem to be the way to go. I would think a subwoofer would be called for with these too.

[Nuance]

Thanks for the info, Jeff.  Is there a guesstimation on what something like that would cost us consumers who aren't interested in building our own (IE just want to purchase a complete pair)?

[JP78]

i always imagine salk speakers as more of a last-step type of solution, probably somewhere in the same  breath as dynaudio mini-monitors.

Last step as in top-notch?

Well, why wouldn't you want your desktop speakers to be top-notch?

turkey - indeed i did mean top-notch, no further improving needed. i would love to have a top-notch solution, but i currently can't afford a state-of-the-art for every system i own: a two channel system, headphone system, and desktop system.  unfortunately i have to prioritize for now and hope to upgrade one day.

i think for several of us it's the same way...we do the best bang-for-the-buck for now and pinch our pennies for that final solution.

[JP78]

Anyways, I too use the AudioEngine A5 and am pretty happy with them.  I think Jim ought to buy a set for comparison, listen to them on his desktop computer at work/home for a while, and then figure out how to make a set that sound even better.  Something about that size or smaller would be good.  I'd probably be willing to pay about a grand for 'em.  My .02 cents worth...

+1, so long as that grand includes some type of amplification. like i said, i'm relatively poor these days .

[dave_c]

Here?s what I think about the A5?s without having heard them.  Audiophiles will upgrade from it because they can?t sit still.  Two components in one?   You don't even get to buy new speaker cables... 
The sickness will get you and you will have to upgrade to separates because you can?t stand not knowing if you could do better with a separate amp.  So as good as they sound now?watchout!  Soon you will have a small tube integrated amp that is just a little too hot and a little too big but sounds soo good you?re willing to take it for the time being?  hahahahaha!   

[JP78]

dave you know you're not well when the desktop amp is larger than the desktop computer .

[dave_c]

Given how small computers are getting now, its pretty easy to have an amp that's bigger. 

Jeff - Those speakers are so nice.  A little bigger than what I was thinking but I like the looks and I bet they sound great. 

[turkey]

i always imagine salk speakers as more of a last-step type of solution, probably somewhere in the same  breath as dynaudio mini-monitors.

Last step as in top-notch?

Well, why wouldn't you want your desktop speakers to be top-notch?

turkey - indeed i did mean top-notch, no further improving needed. i would love to have a top-notch solution, but i currently can't afford a state-of-the-art for every system i own: a two channel system, headphone system, and desktop system.  unfortunately i have to prioritize for now and hope to upgrade one day.

i think for several of us it's the same way...we do the best bang-for-the-buck for now and pinch our pennies for that final solution.

Ok, I misunderstood. I thought you were saying that desktop speakers didn't warrant a top-notch product.