Electrostatic's and Sensitivity

[fr0st]

I've recently had to shift my whole bedroom around to make way for the school year (and associated homework ) and had to reposition my sound system and computer. The only problem is the computer is now dead in a corner so my current speakers (2 ways, 30l boxs) won't fit on the desk or either side on the floor. So in order to get stereo again I need to wall mount something. This is where the electrostats fit in.

The only thing is that i enjoy rather loud music (by some peoples standards). My current speakers are 92db/1w with a 25w gainclone and 120 dual 10inch active sub (100l vented box). Which i think is about 106 db for anything over 120Hz. Can this be matched by electrostats?
A little less is no problem, but space is. They wouldn't be full range due to the raw size of the panels needed, so maybe an 5-8 inch for the midbass to reduce the size needed for the spl i'm after?
I don't mind ditching the gainclone either, i'm not a huge fan of it
As for step up transformers, can a few 8 ohm/100v transformers be used? This would just be an easy alternative from getting proper ones, which can be done (at a much greater cost through..)

Thanks All

Matt

[Coolin]

Hi,

I dont think the cheaper 100V transfomers will get the high voltages you need. Im not sure what the winding ratio is.
You need atleast a step up transformer of 1:50 or more.

Getting enough volume can be done if you indeed leave out the bottom 100-200 hz. How much depends on the size and construction of the panels and the voltages used.

Coolin

[MarcelvdG]

As far as I remember, QUAD ESL-63's can just make a 106dB SPL extrapolated to 1 metre listening distance in short sine bursts. Continuous signals have to be softer. Their sensitivity is 86dB extrapolated to 1 metre at 2.83V RMS. I'm writing extrapolated to one metre, because they are actually intended for listening distances of two metres or more.

However, electrostatic dipole loudspeakers are usually placed at least one metre from the wall, otherwise the wall reflection comes very soon after the direct signal and degrades the subjective sound quality. I doubt if going electrostatic is a good idea if you have insufficient space.

[VictorG]

ditto on the wall comment.

You certianly arnt going to want them right on the wall, and you certianly you wont want them paralell with it.

I really don't think you want electrostats for this app man. The stepups will cost ~75 a pair, but the ***** is in the construction. I mean its doable, but doable with a reasonable budget. This won't be a cheapo project, and if you are already talkin about skimpin on the tranfo costs, you are not going to get a nice sound out of these. And you dont want to cross ESL into midbass, at that point just buy a planar tweeter.

Which brings me to my idea, why no just make some tall skinny guys that would fit well anywhere? And this can be done with spectacular results. personally I would try out the tangbands. Utilizing this driver TB 871s , you can achieve some pretty spectacular stuff. Just do a search on the model number. Cross it over to a nice 6 incher of even the 4 inch sub that TB make (parts express for that), and yoy should be able to get skinny tall guys that can go 70-15k no prob. 87db effic.

B

[fr0st]

Its not meant to be a el cheapo project using saran wrap and old fly screen doors. The main point of skimping out on the transformer is to save the cost and trouble of importing one. I can get 100v transfromers wholesale up to 150w (toroid) and 60w (EL) with 8 ohm windings. All rated between 30hz-20khz. The cores would be suitable but the primary winding isn't (100v). If I dismantle and EL type and rewind the 8 ohm winding as it was and then do the 1:50 winding from there, then would be suitable?
I know there are all kinds of secrets of transformer winding that the manufacturers keep to themselves but i don't think it would make alot of difference since I'd be DIY'ing them.
I'm lucky enough to have a dupont in my city so i have access to mylar and Elvamide (recommended off the quadesl.org site). Preforated metal is easy to come by aswell.
Do wall reflections cause a huge(!) deteriation of sound quality? compared to low end 6.5inch speakers and a gainclone?
(I'm considering an AlephX or similar class A amp to deal with the impedence drops without dieing)
I am moving house in 6 months time which will eventually solve the wall problem but I'd rather something more quality than what i've got at the moment.

Speaker placement would (for the time being) hung off the wall at a 45deg angle (horizontaly)

Thanks for your replys

[VictorG]

Oh, well i didnt realize your commitment to the project.

In that case, Estats are the best! I am jealous of the adventure that awaits, but you should cross in the 120-200 Hz area, and cross over to a real woofer.

If you are looking for a good midpriced woofer, the CSX line by peerless is GREAT. My friend got some Audax carbon fibers which are supposed to be good, though i have never heard them at thier best.

As for the amp, the Haflers sound GREAT for the estats and would save alot of money for the actual stats. I have tried both the dh-200 and dh-500 on stats, and the sound is amazin. Plus you can pick one of these up on ebay dh200 for around 140, dh500 for prob 300.

Are you just gettin started on the estats idea or have you done your research?

Heres a great place just to go, he's a great guy and has made great panels. Has a video of the buildup!

http://www.quadesl.com/diy_esl1.shtml

Good Luck!
Brian

[fr0st]

I've pretty much cleaned google out looking for relevant sites. The only thing i havn't come accross is how to size the different divisions for each cell.
Would it be better to have one large design using the dots approach like you linked or divide the panel into sections for bass, mid and treble according to size?
My guess is the latter has the upper hand in sound quality but sizing i can only make a guess.

And for higher power handling can you make the membrane -> strator distance larger (1/8" opposed to > 1/16") and increase the bias?

[VictorG]

great Qs.

First let me say that even though I have yet to do a full read, Sander's book, Electrostatic Loudspeaker Design, amazon has it, is a great guide.

Yes, you can get an increase in powerhandling, or volume by cranking up the bias and increasing the distance between the stators.

Infact, my best friend just rebuild his up from 1/16 to 1/8. I have a pair like the link i sent you that are 1/8.

I would keep it in this dot orientation. Mixed results when you seperate.

I know primarily use in my dorm a comercial set i got use of ebay, Specta 11s, but i can honestly say the design on that webpage provides for the most intense sweetspot i have heard, it even betters my spectras.

I have them at home though, far out of range of being "beered"

B

[planet10]

ESLs need to breath... they don't work all that well in small rooms.

dave

[SY]

Yes, you can get an increase in powerhandling, or volume by cranking up the bias and increasing the distance between the stators.

When you increase the stator distance, you do indeed increase the power handling, but you reduce the sensitivity and, usually, the max output. The classic case of conflicting design requirements.