2 class AB on ESL

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I have two adcom gfa-545 AB amps, a powered sub for backup. I also have 2 8" carbon fiber drivers. CharlieM has been coaching me on this and any advice, well, I am a sponge. These amps are not bridgeable, they have clipping allerts built in the front of the chassis.
so my question is, can I use one amp per panel or one for both? the lowest load they take is 4 ohm, Charlie informed me that if the panels go down on the load @ 1 ohm I will have major problems. Yes the amps are old, However, I have owned them since I was 17, I am 32 now and still use them.
going on, I like Charlie's TS desighn, as it is very efficient. I am mainly in the car audio busienss for 18 yrs as installer and tech, these do not fit in cars or trucks. SO i will just say that this will be my first build. Charlie has invited me to Savannah Ga at his shop for construction.
I agree from what I have read about difususing the rear of the ESL, makes sence, as the enclosures will be close to the corner of my living room.
Well, thats what i am working with, Charlie was kind enough to give me a parts list! Thank you Charlie:)
Should I go ahead and build the cabinets first? around the 8" driver in a transmission line? that way I can cut out that nasty 1 ohm load on the ESL and just passive cross over around 500-750hz for the ESL and let sub handle the lower end. Charlie has a post and site, check it out! thats what I want to build.... The Jazzman's Electrostatic Loudspeaker Blog very nice and affordable,

thank you everyone on this, i honestly hate doing custom work at the shop(stereo, nav, remote start blaa blaa, ) this is personal, so any information will be treated with response and questions, I have the idea, it is just putting that idea into a something I can touch and share my experience with all the members here. Sincerly, and I hope as well someone helped out in Haiti. GOD bless them.
 
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I have two adcom gfa-545 AB amps, a powered sub for backup. I also have 2 8" carbon fiber drivers. CharlieM has been coaching me on this and any advice, well, I am a sponge. These amps are not bridgeable, they have clipping allerts built in the front of the chassis.
so my question is, can I use one amp per panel or one for both? the lowest load they take is 4 ohm, Charlie informed me that if the panels go down on the load @ 1 ohm I will have major problems. Yes the amps are old, However, I have owned them since I was 17, I am 32 now and still use them.
going on, I like Charlie's TS desighn, as it is very efficient. I am mainly in the car audio busienss for 18 yrs as installer and tech, these do not fit in cars or trucks. SO i will just say that this will be my first build. Charlie has invited me to Savannah Ga at his shop for construction.
I agree from what I have read about difususing the rear of the ESL, makes sence, as the enclosures will be close to the corner of my living room.
Well, thats what i am working with, Charlie was kind enough to give me a parts list! Thank you Charlie:)
Should I go ahead and build the cabinets first? around the 8" driver in a transmission line? that way I can cut out that nasty 1 ohm load on the ESL and just passive cross over around 500-750hz for the ESL and let sub handle the lower end. Charlie has a post and site, check it out! thats what I want to build.... The Jazzman's Electrostatic Loudspeaker Blog very nice and affordable,

thank you everyone on this, i honestly hate doing custom work at the shop(stereo, nav, remote start blaa blaa, ) this is personal, so any information will be treated with response and questions, I have the idea, it is just putting that idea into a something I can touch and share my experience with all the members here. Sincerly, and I hope as well someone helped out in Haiti. GOD bless them.

I think Mavric needs to know is if anyone has experience driving stat panels with Adcom amps because, as we know, some amps have difficulty driving stat panels due to the varying, fequency-dependent impedences (possibly falling as low as 1 ohm at the upper limit of the bandwidth).
 
Hey Mavric, first of all I REALLY hope you stick with it and follow through on building these! There are a lot of tedious little facts, decisions, and trade-offs when building a set of these, but you'll be glad you did when you finally complete.

I do not have any experience driving esl's with the Adcom, and therefore cannot advise either way. I however do own a set of esl/tl's hybrids that I run to VERY loud levels using four channels of an Emotiva xpa-5 powering both the esl's and the 10"driver 8' long transmission line without breaking a sweat. A friend of mine has the same esl panel (15"x42") and the same (peerless 10") driver in a non tapered tl (mine is tapered/more compact) and he uses two hafler dh-500's without a problem either, but if you look up specs on either of these amps they are both rated to only 4 ohms and both drive the upper freq 1 ohm load of the esl's that folks talk about, but are heavy hitters AND have large reserves.

To your 8" carbon fiber drivers, what make/model/specs?
There are certain driver parameters that work better than others to "drive" a TL. There are sources on the web that you will have to scour for that list what these more favorable characteristics are. There is quite a bit of "opinion" out there as to these claims but I can tell you from months of trying to make a scan speak 8545 work in a tl... it ain't gonna happen (not for the freq response desired), I have built dozens of test boxes, different line folding etc. and have come to the conclusion that only certain drivers work for a good tl. Also, tl design has evolved a bit in the last decade or so, I suggest you look up the work of M.J.King design. (don't feel obligated to buy anything) just search the web a bit and read between lines a little.

Hope none of what I write here confuses or discourages you, just relating what I know and what I have tested

Cheers, Steve

Any questions, fire away (or not) up to you
 
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My Carver TFM25's don't have any problems vertically bi-amping my 10" woofer/12"x48" hybrids (one amp dedicated to each speaker with one channel driving the woofer and the ther channel driving the stat). However, I would have some concern with bridging an amp to mono and driving a stat panel with it.
 
Have no 545 experience , have used only 555 and 565 monoblocs. Both will drive a 1 ohm resistive load to reasonable levels after upgrading the fuses and of course with fans. Your ESL is a big "capacitor " represent a different sort of load , not sure if the 555 can handle such , the 565 for sure.

You should upgrade to at least a 555 ( they are inexpensive ) and use the 545 on the bass, i believe your ESL get's to 1 ohm above 10 K .
 
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Steve :

I had contacted Emotiva regarding there Mono blocs operating @ 1 ohm and they did not recommend them to be used at 1 ohm , nor did they recommend purchasing any of there models to do so .

It appears one Apogee forum member tried such and there were issues driving scinnies.. sad as i had really wanted to try one ..
 
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ESL Hopeful

Thank you everyone, I visited Charlie Sunday and got a taste of what I have allways wanted. I am NOT discouraged, more encouraged than anything! As far as the Adcom, they are non bias two channel with clipping allert built in as well, My set up will be allmost like Charlie's, I am going to aquire a pre-amp cross over for the stats and you a dedicated sub amp as well, the same as Charlie. He examined the amp, and told me for the build they would be fine as I have two of them. I know this is not an over night success, I am patient and the pleasure of hearing a set up close and personal. He also let me borrow the cook book as called, si I need to do more reading and reading.
The 8" sub has allways been in a TL enclosure, a very large one. I forgot to mention that I have four of em, just in case.

> one amp on the ESL
> one amp for drivers in TL
> Powered sub for that kick in the A@# if you know what I mean


As soon as money comes, I will purchase the stators, as the coils seem come cheap or expensive. The copper tape and other things that you recommend in stages as purchasing for the build are appreciated. Once again thank you everyone.:)
 
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