cls updated

[teslaboy]

I am new posting but not new viewing .
I collect esl speakers and mod a few.
i have two projects i am working on both are martin logan CLS 1 and 2.
Project 1. ML CLS 1 bypassing the original transformer with a plytron
esl toroid 75-1 transformer. Do i eq the speaker from scratch or modify the original ?

Project 2 ML CLS 2Z using one original transformer for bass and a toroid transformer for highs, like the acoustat MK 121 interface.
Do i use the acoustat values or other ?
both speakers will be fed bias voltage from a 120 v-6kv transformer connected to a variac for a variable 0-7.2 kv .
any input from the esl community is appreciated .
I have followed Calvin for years and wish to thank him for his inspiration

 

[bigfishe]

I would like to hear some thoughts on this mod ?
CLS1 owner here.

 

[bigfishe]

Anyone know about this ESL transformer?

 

[tyu]

CLS interface Set up

I to have CLSs...An Acoustats less see if others who have Diyed ESL Well give us some input on how there interface are wired....I have found that the best sound an the most output come from runing my CSL or Acoustat Interfaces like the CLS2z were there is no Center Tap used....In All other here we see the Center tap is ran to ground...Or as we no it all ran to the Neg output of the amp none of the setups i have But the Acoustat run the earth in from with the AC...But i float that as dose ML on all i have owned...
The ML run the Frount of the panel that would be in the nom. on one end of the transfourmers winding,,,But look at the 2z ...one end of the winding is now on the neg in put..I move this to the back of the panel because the front of the panel is the only one with the bias feed on it....An it now holds the full windind it drives the front panel only.. an gives 3db more output..thay wonted the front to be ...socalled grounded.. so you would not get Zapet...just keep the phase right an it works ...fine...I now have my Acoustats runing with Two T2 for the interfaces..an one 5ohm 100w on the pos. input...just like the CLS2z... All others Caps an res are out,I find this to sound best...Now as for runing the CLS as the Acoustat 121 interfase is set up with two tranfourmers ...it dose not work well for me the CLS panel Can not move as much Air as the Acoustat...you can say what you think if you have done the setup.....An Moray James my have some input...

 

[tyu]

Boy you would think that out of over 400 hits there wound be someone to give some in put.........well that life with ESLs..

 

[moray james]

teslaboy and tyu: I worked on a pair of CLS a lot of years ago and I ended up fitting them with Acoustat Mk121 interfaces with new caps and some tweaks. That was the best configuration that I came up with at the time and they sounded much better than with the stock interface. As tyu said you cannot run a ML panel as hard as an Acoustat because the ML are curved and so not symetrically balanced stator spacing wise (small spacing on one side).
I would suggest you get a set of Acoustat interfaces and optimize them and use that as a reference while you play with your other ideas. I do think that flat panels are a better way to go by that is your decession as the ML`s do look good. See what you can do and if you can better the Acoustat interfaces I think that you will have done something special. My experience was that as soon as I ran a panel with two transformers it did not aound as good as running one transformer per panel. Hope this is of some interest. Best regards Moray James.

 

[tyu]

Moray
Thanks for your input as always.....ANYONE ,anybody....lot of you diy guys out there,
Just say this is any ESL you have, how,s is the panel wired to the transfourmer???? Do you bring the earth in to the bias,an centap,an the neg of the amp,or float all an use just the amps neg.???
An as said thanks for your input....