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RE: SoundLab transformer MOD

Well it been 10 good day with this type of Mod in on my Acoustats
so now like lew an some others i am looking at a cap on the input of the high frc tranfourmers primary ....so i put a big 40mf oil cap

This is how it looks on paper...Ralph has to say..

The only issue with the 1st pathway is that the HF toroid should not have low frequencies applied to it else it could distort due to saturation. That is easily solved by simply decreasing the cap value, which has the added benefit of greater transparency.
In some cases the cap is easily decreased as there are several in parallel and one can be simply cut out, in other cases the cap has to be replaced outright.

But then there this truth some of us beleave...
Tried it without the cap, did not experience saturation, so why put it there? Borrowing a line from you: "the cap can not ADD to the transparency, can it?"

An there more...
What I am saying is that the road may not have ended there- if the impedance can be further raised at high frequencies the door would be open to lower powered amps and lower distortion out of higher powered amps.

Very similar argument to what you had proposed. There are upsides and well as down sides of using capacitors. For me, capacitor sounds too obtrusive and should be avoided where ever possible.

Anyone who persist with ELS (and its many shortcomings) are in it for low level detail and its magical midrange, so I doubt your suggestion of a cap is a long term answer for this group of people.

More yet from Ralph

So- the idea here is to see if the impedance can be raised (thus reducing amplifier distortion) by examining the way the bass transformer and the new transformer interact at frequencies above the 'cutoff' of the LF transformer. Maybe its not a concern, but it may well prove worth looking into

Then Lew
All those lovely sounds are going through that horrid capacitor, which is in parallel with an equally lo-fi sand cast resistor, to form a filter which I gather protects the speaker from low bass transients OR is needed to equalize the frequency response. Ironic.

To me this gets funny that Dr.west would ever do the same thing
Dr.West uses lo-fi sand cast resistor in any ESL....this is moronic
But we all no this....back to My 40mf cap...
well here what it sounds like to me... if you have ever used a good pasive preamp...with no gain... that what i here with nothig in front of the high frc tranfourmer....if the input is at it best you get the best output out of the ESL...so with the cap in...the topend get rolled down.. like 1/2 db...an the cap can sound a little less detail and its magical midrange....
So then i get to looking at all the RF..an other hash that coming in to the ESL...like AM..FM..TV...an others

So i get some help from My old MartinLogans...Thay drop a Zobel in on there High frc tranfourmers all the time.....So i ran a 8ohm 200 watt from just in front of the 40mf cap down though a 20mf polstrine to the Neg input of the tranfourmers...

My ESL have been set up this way for 3 days .....an it sounds like i now have a Vary good preamp in ...an it the best yet...We got get the noise OUT....this is one way of doing it..an it sounds sweet....So if you do use a cap.. this works....NOw i am useing the same 50watt tube amp to drive this.... so it is not eating power with the Cap an Zobel in...With the cap an Zobel in i may be geting a littel more output....If it was less output... it would be the deal braker.....Goodluck

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  • RE: SoundLab transformer MOD - tyu 09:16:29 06/18/12 (0)


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