The best thing to do to the SL3 is to put the Ascent i crossover in,the SL3 has all the same parts you need 2 caps,this sounds much better, It takes the Cap an put it in front of the res.In the sl3 set up the res are frist so there hit with fullrang an thay ring,move them behind the cap like thay did an no lows hit the res there for no ringing.
I have done this to my MLSL3 an sound is much better you can get the Ascent crossover at MLfan club,i have other mods for the SL3 also goodluck
I have done this to my MLSL3 an sound is much better you can get the Ascent crossover at MLfan club,i have other mods for the SL3 also goodluck
I wonder what the heck TYU was saying, frankly I was thinking of selling these speakers but if there is a way to get better bass out of these I might try. I have had tremendous luck upgrading caps and resistors on cone type speakers so maybe it's time to try to upgrade these units, if anyone has any practical information please post it, Thanks much, Rob
tyu
look the SL3 Crossover,
Two mods,
Take the Coil out of The cen.tap,there using only 1/2 the Tranfourmer,put nothing on the cen.tap,you can see the coils is on the neg.input, it a wire!It turns off 1/2,
Next i Get rid of the What i call the Limiter, Mr Powers called it a ML-dce
It a Diode bridg an mofet setup that rides the panel input,an as the input gos up it take power off the panel.I have used this Dce on fullrang ESL like Soundlab an Acoustats An can sound great,$10 you can diy,funny sounds just like a tube-fet can sound good if you have 1kwatts you wont to pump in the the SL3s Most dont
Eats output out of the panel,to get better bass you got to get the panel right.
look the SL3 Crossover,
Two mods,
Take the Coil out of The cen.tap,there using only 1/2 the Tranfourmer,put nothing on the cen.tap,you can see the coils is on the neg.input, it a wire!It turns off 1/2,
Next i Get rid of the What i call the Limiter, Mr Powers called it a ML-dce
It a Diode bridg an mofet setup that rides the panel input,an as the input gos up it take power off the panel.I have used this Dce on fullrang ESL like Soundlab an Acoustats An can sound great,$10 you can diy,funny sounds just like a tube-fet can sound good if you have 1kwatts you wont to pump in the the SL3s Most dont
Eats output out of the panel,to get better bass you got to get the panel right.
Acsent i crossover
This Is the best thing to do with the SL3,same panel as the Ascent,an i.
I have had 5pr of the ML Aerius i,two pr of SL3 one with the Limiter one with out,Requst had the limiter,CLS,II,Thay can be fine speakers but like most just a littel work to get the best out of them,Best Mid on the Aerius
but i am geting better out of the SL3 today,
This Is the best thing to do with the SL3,same panel as the Ascent,an i.
I have had 5pr of the ML Aerius i,two pr of SL3 one with the Limiter one with out,Requst had the limiter,CLS,II,Thay can be fine speakers but like most just a littel work to get the best out of them,Best Mid on the Aerius
but i am geting better out of the SL3 today,
Hello tyu,
Very interesting that Martin Logan makes use of a limiter without advertising it like QUAD does.
Perhaps it is similar to the early versions of the QUAD ESL63 limiter but using a MOSFET instead of BJT power transistor.
You mention it could be DIY'd for about $10.
Can you post a schematic with part numbers or a close up picture of the limiter PC board?
Hmmmmm...I wonder if the MOSFET board ticknpop mentioned in his CLX mod thread is actually a limiter board rather than an audio-detect switch like he had thought.
http://www.diyaudio.com/forums/planars-exotics/179196-martin-logan-clx-mods.html#post2402955
Last edited:
From CLX post
5. The Fet turn on board (the lower PC board with heat sinks) has 4 of 0.33 uf/ 250 volt caps on it bypassing the IRF 640 Power fets - Replace with MIT PPFXS 0.33 uf.
This is Not A TURN ON Setup!
The Quad setup,I think turn off the panels if the amp clips.
This Dose Not!
What This Dose Is Takes the AC an the DC if the Amp clips, AN the Fets Get HOT not the Tranfourmer,vary cool right,Mr Jim Powers Sead there were people Driving there speaker hard with amp like the Krell 600 mono amps That could put out 2k watts an this help not over drive the Tranfourmers.
Mr Powers an ML NEVER CALLED THIS A LIMITER! i did, i well get a pix
Mr Jim Powers Is not with us Anymore,good man gave me a lot of info
thanks
5. The Fet turn on board (the lower PC board with heat sinks) has 4 of 0.33 uf/ 250 volt caps on it bypassing the IRF 640 Power fets - Replace with MIT PPFXS 0.33 uf.
This is Not A TURN ON Setup!
The Quad setup,I think turn off the panels if the amp clips.
This Dose Not!
What This Dose Is Takes the AC an the DC if the Amp clips, AN the Fets Get HOT not the Tranfourmer,vary cool right,Mr Jim Powers Sead there were people Driving there speaker hard with amp like the Krell 600 mono amps That could put out 2k watts an this help not over drive the Tranfourmers.
Mr Powers an ML NEVER CALLED THIS A LIMITER! i did, i well get a pix
Mr Jim Powers Is not with us Anymore,good man gave me a lot of info
thanks
![reQuest%20tweak%20photo%203[1] (4).jpg](/community/data/attachments/198/198689-47b8b1e0be79083dbe6ca426207f15c3.jpg)
Thanks for the parts list.
It sounds essentially identical to the simple limiter circuit I have been experimenting with.
See attachment for schematic of the latest version of my limiter.
Basically, once the amplitude of the audio signal reaching the transformer primary exceeds the zener voltage, it starts to turn on the MOSFET which draws more current thru the series damping resistor to drop the voltage down to the desired level. The larger the amplitude exceedance, the harder the MOSFET is turned on. MOSFETs can be paralleled for use with lower value damping resistors or extremely powerful amplifiers. I have been using IRF-540s.
Like you said, the limiter is nice to have in case owners use larger amplifiers than recommended.
It avoids any problems with transformer core saturation or air ionization damaging the diaphragm coating. I just found it interesting that ML did not advertise that their ESLs incorporated protection against being over driven. I think it would be a good selling point. But, I guess it could also be seen by some as a crutch, or a non-essential circuit that could only have bad effects on the sound quality whether or not it was ever tripped.
Two possible reasons why ML chose to use discrete diodes instead of a bridge rectifier:
1) Cost. In large production quantities it may be cheaper to use the discrete diodes.
2) Speed. You didn’t mention the exact part numbers for the diodes, but it is possible that the discrete diodes can turn on and off faster and cleaner than a bridge rectifier.
Attachments
Yes You Have it. The Res. is 1k an thay use two Zeners 1n4759a an 1n4752a in parall
An it set up as you have this An it works great,An sounds like a Fet amp i have Diy ed Pass mosfet amps, MartinLogan panel are so week Even New Thay only feed the HV bias on the Right side of the panels,this means that the right speakers putout less from day one thay have got to be redone to give all that thay can,Now that i have done this i could use the Limiter,
Here the deal i had two pr SL3 at the same time,one with an one with out the limiter
I got more output out of the panel that did not have the limiter
How do you think it sounds on you set up ,an is your ESL fullrang,Thay well get HOT
Cool good job An thanks for you info
An it set up as you have this An it works great,An sounds like a Fet amp i have Diy ed Pass mosfet amps, MartinLogan panel are so week Even New Thay only feed the HV bias on the Right side of the panels,this means that the right speakers putout less from day one thay have got to be redone to give all that thay can,Now that i have done this i could use the Limiter,
Here the deal i had two pr SL3 at the same time,one with an one with out the limiter
I got more output out of the panel that did not have the limiter
How do you think it sounds on you set up ,an is your ESL fullrang,Thay well get HOT
Cool good job An thanks for you info
In posting #12 you only mentioned one zener per module.
1N4759A = 62V zener diode
1N4752A = 33v zener diode
If these two zeners were put in parallel, the 1N4759A would never conduct because the voltage across it would never exceed 33V since the 1N4752A would hold the voltage at this level. Perhaps you meant they were wired in series. That would mean the limiter would kick on at a voltage input level of about 100V which would be equivalent to about 600Watts into 8 ohm.
I have used the limiter with fullrange ESL and with hybrid. I designed my ESLs to handle 250W/8ohm since this is the highest amplifier power level commonly available. Above this level, the transformers start to saturate, and the air in the gap can ionize. Both result in fuzzy distortion sounds when driven with a friends 600Watt amplifier. The limiter keeps this from happening. I haven't really noticed any difference in the sound quality with the limiter hooked up. Oh, and YES, the MOSFETs can heat up rather quickly as all the excess voltage is diverted from the ESL and turned into heat.
Can you tell me what the part numbers are for the 4 diodes used to make up the discrete bridge rectifier circuit?
Curious to know if they are using fast recovery diodes or traditional silicon rectifiers.
Thanks again for sharing this information.
Hi Thanks for your time
You say
In posting #12 you only mentioned one zener per module.
1N4759A = 62V zener diode
1N4752A = 33v zener diode
If these two zeners were put in parallel, the 1N4759A would never conduct because the voltage across it would never exceed 33V since the 1N4752A would hold the voltage at this level. Perhaps you meant they were wired in series. That would mean the limiter would kick on at a voltage input level of about 100V which would be equivalent to about 600Watts into 8 ohm.
The Last thing i got From Mr Powers was info on the ML Prodigy,
The panels on the Prodigy Were Big an thay have Two Transfourmers ,An i need to see how thay had them setup,all the Transfourmers werthe same SL3,all the way To the Prodigy there are just diff taps used,
No,thay have the Limiter on a board an thay used a doide bridg an the RC204 an a IRf 540n fet ,the Two zeners above an 1k res,
It was that the Two tranfourmers could take a lot of power,big panel,
An i think that the same limiter like you have came up with is good like the one in The SL3an all other with one tranfourmer,
Can you tell me what the part numbers are for the 4 diodes used to make up the discrete bridge rectifier circuit?
Curious to know if they are using fast recovery diodes or traditional silicon rectifiers.
No,i only have the Prodigy power syple.
not high speed,there Like RAT Shik parts i like the 3amp 1kwatts an The irf510 thay have work but 540willtake more V i think
Now have seen the tranfourmer setup that used on the 4 wire panels???
stent to the UK that had to grond the panel,not like most, not PUSHPULL??
Vary cool you can get more output out of any setup
You say
In posting #12 you only mentioned one zener per module.
1N4759A = 62V zener diode
1N4752A = 33v zener diode
If these two zeners were put in parallel, the 1N4759A would never conduct because the voltage across it would never exceed 33V since the 1N4752A would hold the voltage at this level. Perhaps you meant they were wired in series. That would mean the limiter would kick on at a voltage input level of about 100V which would be equivalent to about 600Watts into 8 ohm.
The Last thing i got From Mr Powers was info on the ML Prodigy,
The panels on the Prodigy Were Big an thay have Two Transfourmers ,An i need to see how thay had them setup,all the Transfourmers werthe same SL3,all the way To the Prodigy there are just diff taps used,
No,thay have the Limiter on a board an thay used a doide bridg an the RC204 an a IRf 540n fet ,the Two zeners above an 1k res,
It was that the Two tranfourmers could take a lot of power,big panel,
An i think that the same limiter like you have came up with is good like the one in The SL3an all other with one tranfourmer,
Can you tell me what the part numbers are for the 4 diodes used to make up the discrete bridge rectifier circuit?
Curious to know if they are using fast recovery diodes or traditional silicon rectifiers.
No,i only have the Prodigy power syple.
not high speed,there Like RAT Shik parts i like the 3amp 1kwatts an The irf510 thay have work but 540willtake more V i think
Now have seen the tranfourmer setup that used on the 4 wire panels???
stent to the UK that had to grond the panel,not like most, not PUSHPULL??
Vary cool you can get more output out of any setup
One more time Gess
You say
In posting #12 you only mentioned one zener per module.
1N4759A = 62V zener diode
1N4752A = 33v zener diode
If these two zeners were put in parallel, the 1N4759A would never conduct because the voltage across it would never exceed 33V since the 1N4752A would hold the voltage at this level. Perhaps you meant they were wired in series. That would mean the limiter would kick on at a voltage input level of about 100V which would be equivalent to about 600Watts into 8 ohm.
The Last thing i got From Mr Powers was info on the ML Prodigy,
The panels on the Prodigy Were Big an thay have [Two Transfourmers]An i needed to see how thay had them setup,all the Transfourmers were the same as SL3,all the way To the Prodigy. There are diff taps
In Full rang ESL i would use two transfourmers for the top,an two for the bottem,setup like the Acoustats an CLS2z an forget the limiter.What do you think???
you say
Can you tell me what the part numbers are for the 4 diodes used to make up the discrete bridge rectifier circuit?
Curious to know if they are using fast recovery diodes or traditional silicon rectifiers.
NO.Parts no.
Thay have the Limiter Belt in to the Bias board an thay used a diode bridg. It is a RC204 an a IRf 540n fet ,the Two zeners above in Parallel an 1k res.
It was that the Two tranfourmers could take a lot of power,big panel,
An i think that the same limiter like you have came up with is good like the one in The SL3 an all other with [one tranfourmer ]on the Panel. It Can Need the Limiter If push,et
ESL Panel set up
Now have seen the tranfourmer setup that used on the 4 wire panels???
Thay were sent to the UK Thay had to grond the panel,not like most, not PUSHPULL Well qus ?? I have Used this on Fullrang ESLs
Vary cool you can get more output out of any setup !
Thanks
You say
In posting #12 you only mentioned one zener per module.
1N4759A = 62V zener diode
1N4752A = 33v zener diode
If these two zeners were put in parallel, the 1N4759A would never conduct because the voltage across it would never exceed 33V since the 1N4752A would hold the voltage at this level. Perhaps you meant they were wired in series. That would mean the limiter would kick on at a voltage input level of about 100V which would be equivalent to about 600Watts into 8 ohm.
The Last thing i got From Mr Powers was info on the ML Prodigy,
The panels on the Prodigy Were Big an thay have [Two Transfourmers]An i needed to see how thay had them setup,all the Transfourmers were the same as SL3,all the way To the Prodigy. There are diff taps
In Full rang ESL i would use two transfourmers for the top,an two for the bottem,setup like the Acoustats an CLS2z an forget the limiter.What do you think???
you say
Can you tell me what the part numbers are for the 4 diodes used to make up the discrete bridge rectifier circuit?
Curious to know if they are using fast recovery diodes or traditional silicon rectifiers.
NO.Parts no.
Thay have the Limiter Belt in to the Bias board an thay used a diode bridg. It is a RC204 an a IRf 540n fet ,the Two zeners above in Parallel an 1k res.
It was that the Two tranfourmers could take a lot of power,big panel,
An i think that the same limiter like you have came up with is good like the one in The SL3 an all other with [one tranfourmer ]on the Panel. It Can Need the Limiter If push,et
ESL Panel set up
Now have seen the tranfourmer setup that used on the 4 wire panels???
Thay were sent to the UK Thay had to grond the panel,not like most, not PUSHPULL Well qus ?? I have Used this on Fullrang ESLs
Vary cool you can get more output out of any setup !
Thanks
I am using a 62V zener diode in my MOSFET limiter circuit.
Series damping resistance is 2.25 ohm, 40Watt.
ML uses a series damping resistance of 1ohm 60Watt.
See attachment for identification of the 3 parallel resistors that make up this resistance.
Their crossover circuit also has a capacitor, CX2, in series with the audio signal going to the transformer primary. So, there would be voltage drop across CX2 as well as the series damping resistance when the limiter starts to kick in. My ESL only has a series resistance, no capacitance.
Attachments
So on the Re.
if you can help, what is the Re go from the sorse an gate of the Mofet your using?? On the logan limimer it look 1watt
An well i need to drop the zener too Lower V as its in being feed in front of the cap?
Dou have the CLS Xover an there Tone setup
Thanks
if you can help, what is the Re go from the sorse an gate of the Mofet your using?? On the logan limimer it look 1watt
An well i need to drop the zener too Lower V as its in being feed in front of the cap?
Dou have the CLS Xover an there Tone setup
Thanks
Attachments
![clsfiltercomp[1].jpg](/community/data/attachments/206/206171-13bc604c423f869c006681d7da6d96f1.jpg)
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