DIY Hybrid Electrostats

J

jazzman53

Audioholic Intern
Hi all,

I just found and joined this site... looks like a great place!
Actually, I'm a newbie to home theater, even though I've been into audio gear for many years.

If anyone is interested in high quality DIY hybrid electrostatic speakers I've got a website dedicated to building them fairly cheaply (around $800 a pair).

Since this is my first post here, I can't post a link to the website yet but it's easy to find-- just do a Google search for "Jazzman's ESL Page".
Enjoy!
Jazzman
 
GranteedEV

GranteedEV

Audioholic Ninja
Nice website!

The bass section appears to be a monopole source. Did you experience any audible power response mismatch at the crossover?

I would imagine a cardioid or dynamic dipole bass source would blend better.
 
J

jazzman53

Audioholic Intern
Nice website!

The bass section appears to be a monopole source. Did you experience any audible power response mismatch at the crossover?

I would imagine a cardioid or dynamic dipole bass source would blend better.
Anything that's said about a flat panel electrostat should include the caveat "in the sweet spot".

I think a vertical array of dipole woofers would indeed blend better with the stat panel than the single omni-woofer I'm using-- insofar as the bass array I described would remain balanced with the stat panel in the near field and in the far field also. Whereas, the single omni-woofer in my setup is only balanced at the far field "sweet spot".

The stat panel is a quasi-line source so it's SPL falls off at only 3db for each doubling of the distance from the speaker; whereas the woofer output falls off at at twice that rate (6db) with each doubling of distance from the speaker. Accordingly, the bass and stat panel can be balanced but only at a given distance from the speaker. Fortunately, I can use the EQ and amp controls to exactly balance the woofer and stat panel at any distance I choose, just not at all distances simultaneously. Obviously, I tune it for balance at the focal sweet spot (I use a room correction RTA with a microphone at the sweet spot to tweak it in).

Dipole bass is wonderfully uncolored but also inefficient so a lot of cone area (multiple woofers) would be needed to get bass output comparable to the SPL of the stat panel.

Since my budget was limited, I made some compromises but I think I did so wisely without giving up much fidelity by comparison. I opted for the TL bass to save money and floor space, as a dipole multi-woofer array would have required twice the floor space at twice the cost.

The alleged "downside" is that the speakers with omni-bass sound bass-heavy everywhere except at the sweet spot because the woofer is omni-directional and the stat panel isn't (the treble falls off a cliff as soon as you move 1 foot out of the sweet spot). But in reality, choosing the TL bass over a dipole array doesn't really have as much "downside" as you might think-- and I will explain why:

The fact is, a flat panel electrostat is so ultra-directional that you wouldn't want to listen to it from anywhere except inside it's miniscule sweet-spot anyhow. So it really doesn't matter that much that the TL bass is only balanced with the stat panel at the focal sweet spot and becomes unbalanced as you move out of the sweet spot.

Actually, I was stunned to experience how well the TL bass blends so seamlessly with the stat panels in the sweet spot (there's that caveat again).

The downside with a flat panel stat is that it's so directional that the sweet spot is only a foot wide, which makes it useless for parties (unless all your guests are sitting in your lap!). Likewise, the upside with a flat panel is that it's so directional that your ears receive a single coherent wavefront with practically no room reflections so the imaging is absolutely superior to anything else.

I think a dipole bass array is unbeatable but you can get pretty great sound with a TL too, if you set it up right, and save money too.
 
Last edited:
darien87

darien87

Audioholic Spartan
Wow. Home-made electrostat's, that's pretty impressive.
 
I

Impelled

Junior Audioholic
I'm building some TL (fronts) Ribbon speakers, just have one rear ribbon based speaker running and it sounds awesome!
The tweeters are also extremely directional, but still sound fantastic when not in the sweet spot, just not as sweet :)

But I'm saddened I didnt catch a post like yours earlier, I'd love to have a set of Electrostatics!
I might just make some anyway :D
 
J

jazzman53

Audioholic Intern
Thanks guys... it's fair to say I'm on a mission to promote DIY ESL's and to make them simple and inexpensive. Historically, finding suitable transformers at an affordable price has been the biggest impediment -- but those cheap toroids solved that problem (at least for hybrid panels).
 
jeffsg4mac

jeffsg4mac

Republican Poster Boy
Very impressive and beautiful work! Thats a bit more DIY than I would care to get into though. Think I will just stick with a set of Maggies or Logans.:)
 
J

jazzman53

Audioholic Intern
Very impressive and beautiful work! Thats a bit more DIY than I would care to get into though. Think I will just stick with a set of Maggies or Logans.:)
I think the new 3.7 Maggies may be the best value in Hi-Fi.
BTW, you have a great website (you'd make Ronaldus Magnus proud).

Charlie
 
TLS Guy

TLS Guy

Seriously, I have no life.
Hi all,

I just found and joined this site... looks like a great place!
Actually, I'm a newbie to home theater, even though I've been into audio gear for many years.

If anyone is interested in high quality DIY hybrid electrostatic speakers I've got a website dedicated to building them fairly cheaply (around $800 a pair).

Since this is my first post here, I can't post a link to the website yet but it's easy to find-- just do a Google search for "Jazzman's ESL Page".
Enjoy!
Jazzman
First of all a very warm welcome to you as a new member of these forums.

Your craftsmanship is worthy of the highest praise.

I would imagine the low Q of the TL blends much better than the ML hybrids.

With a crossover at 200 Hz the bass driver will be a full space radiator, however it will have a radiation pattern different from the ES panel. I would think however that the results are good as you are in territory where the ear is not highly sensitive to these discontinuities.

I note your TL pipe has little if any taper. If there had been a 4/1 reverse taper, the driver would have assistance over a greater range.

I have browsed your website on a number of occasions, and found the materiel to be well presented.

Have your measured the maximum spl at your preferred seating position?

As far as Quads, method of tensioning the mylar diaphragm, it was a complex jig using pulleys and weights. Peter demonstrated it to me himself. The membrane was painted with Peters secret emulsion. He personally took me through the assembly of a Quad ESL 63.

Anyhow, I hope you have a long stay on these forums.
 
J

jazzman53

Audioholic Intern
First of all a very warm welcome to you as a new member of these forums.

Your craftsmanship is worthy of the highest praise.

I would imagine the low Q of the TL blends much better than the ML hybrids.

With a crossover at 200 Hz the bass driver will be a full space radiator, however it will have a radiation pattern different from the ES panel. I would think however that the results are good as you are in territory where the ear is not highly sensitive to these discontinuities.

I note your TL pipe has little if any taper. If there had been a 4/1 reverse taper, the driver would have assistance over a greater range.

I have browsed your website on a number of occasions, and found the materiel to be well presented.

Have your measured the maximum spl at your preferred seating position?

As far as Quads, method of tensioning the mylar diaphragm, it was a complex jig using pulleys and weights. Peter demonstrated it to me himself. The membrane was painted with Peters secret emulsion. He personally took me through the assembly of a Quad ESL 63.

Anyhow, I hope you have a long stay on these forums.
Thank you for the kind comments, TSL Guy.
BTW, I just visited your photo page and, OMG what a setup! That room must have taken some serious inspiration and thought and time (not to mention $$$) to create.

When I started my ESL project, I had very little money (got an ex-wife to support), no prior experience with ESL's or electronics, and certainly no idea what I was getting myself into with those TL bass cabinets.

I attempted to model the TL using MJ King's Mathcad program but never could figure it out-- it's the sort of thing that could end a guy up in a psycho ward. I eventually just gave up trying to understand it and just went with Roger Sanders' generic TL guidelines, from his ESL Cookbook. Fortunately, it worked out very well.

As you can see, my power supplies and transformer setup is about as simple and inexpensive as it gets. No doubt those cap/diode cascade power supplies, as fed right off 60hz house current, have tons of ripple, and I was concerned it would be audible, but in fact it isn't, and I'm now confident you would never hear any ripple-effects in the speakers provided the panels have no leak paths draining charge off the diaphragms.

I got lucky with those cheap toroids too-- bought them on a whim not knowing how they might sound or if they might short out and smoke my amps, but they too worked fine and sound fantastic. In fact, those cheap toroids give much better high frequency response than some expensive EI core audio trannys (wound specifically for ESL's) that I had originally purchased and used.

I don't have any measurement equipment/software so I can't provide any measurements of my speakers. I only have the digital crossover and EQ, which gives me great tuning flexibility. I haven't measured max SPL either but they can play louder than I care to listen (they won't blow the windows out but they will blow women's panties right off-- this I have confirmed but my gf says that could happen anyway, lol).

The only problem with my speaker design is that the cabinets are so complex and time-consuming to build that I hesitate to recommend them to others. As time permits, I'm drawing up a simpler design to post on my website, which will use the same panels and electronics, but with a simple sealed or ported box for the woofer. I want to post a drawing on my website that anyone can build.

The website is a labor of love, which I created as a resource for others like myself, who don't have a lot of money or prior experience with electronics. And I really enjoy getting emails from all over the world. Quite a few people have built their own ESL's using my website as a guide, and they write to me raving about how good they sound-- that's just hugely rewarding.

Have a great day!
Charlie
 
GranteedEV

GranteedEV

Audioholic Ninja
I attempted to model the TL using MJ King's Mathcad program but never could figure it out-- it's the sort of thing that could end a guy up in a psycho ward. I eventually just gave up trying to understand it and just went with Roger Sanders' generic TL guidelines, from his ESL Cookbook. Fortunately, it worked out very well.
I struggled with the worksheets for a while too. I've got a pretty good hang of the basic tapered TL and ML-TL worksheets now though. I've yet to try my hand at the TL-sections worksheet. THey're actually rather simple on a whole.
 
J

jazzman53

Audioholic Intern
Update:

Big change to my diy ESLs:
The original beamy perforated metal stators are GONE-- replaced by insulated copper wire stators that employ electrical segmentation to bend the wave front from planar to cylindrical.

The details and build photos are shown on my website HERE

My speaker with the new segmented wire panels:
 
TLS Guy

TLS Guy

Seriously, I have no life.
Update:

Big change to my diy ESLs:
The original beamy perforated metal stators are GONE-- replaced by insulated copper wire stators that employ electrical segmentation to bend the wave front from planar to cylindrical.

The details and build photos are shown on my website HERE

My speaker with the new segmented wire panels:
That is an intriguing approach to solve the beaming problem of panel loudspeakers. Also that is a nice solution to the arcing problem.

I bet those are really nice sounding speakers.

DIY speaker construction is at it heart all about constructing better speakers and besting the commercial efforts, the vast majority of which have poor to mediocre performance.
 
J

jazzman53

Audioholic Intern
That is an intriguing approach to solve the beaming problem of panel loudspeakers. Also that is a nice solution to the arcing problem.

I bet those are really nice sounding speakers.

DIY speaker construction is at it heart all about constructing better speakers and besting the commercial efforts, the vast majority of which have poor to mediocre performance.
TLS Guy,

Your studio is (WOW!) fantastic—obviously the product of a serious psychosis :)

I love your transmission line speakers. I can only imagine they must sound wonderful. In fact I recently heard a pair of highly modified Tyler Acoustics speakers, which use the exact same drivers I see in your speakers, and I was completely blown away by them. The mods included re-bracing & stuffing the cabs and the original crossovers were eplaced by the most outrageous outboard passive crossovers I’ve ever seen—each crossover costing $7,500 and housed in its own custom built aluminum cabinet with slide out access drawer (photo below-- the psychosis is epidemic...)

passive.jpg
 
J

jazzman53

Audioholic Intern
My friend and ESL guru Steve Bolser posted this on the DIY Audio Forum:

" Indeed, symmetrically segmented flat ESLs can produce dispersion patterns that best most any other ESL (or dynamic loudspeaker for that matter) in broad uniform coverage, and directivity that trends smoothly with frequency. It has been fun exposing people only familiar with flat un-segmented panels(attachment #1), 30 deg arc curved panels (attachment #2), to the smooth/broad coverage of properly segmented flat ESLs(attachment #3). Often they simply don’t believe what they are hearing based on the big flat panels their eyes are seeing. They have to get out of the listening chair and walk up to the panels to check things out, and then wander back and forth across the listening area."

 
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