Acoustat Spectra11 mid peak Fix
Back in the 90s when I got my first pr of Acoustat Spectra 11, I lov the sound...
But after about 30min...I got a head headaches....Wow that sucket….so move on to the 1+1,2+2s....
Then got pr off CL...2015...Still had the peak in the mids others have found an
Bolserst posted about this...So now we know.. it not just me that hearts the mid peak.
Spectra 11 have been showing up on CL at fair prices ...so now I have pic up 5pr ....All the Bias have been low on all 5 pr ...an thats lead to minny post here about fixing the bias part of the Spectra11....so you must get 85-90 volts at the end of the 500mg ohm panels feeder resistor right were it feeds the wire to the panel!..... to get full output of the panels an match the bass driver output so you can hear how great these speakers can sound.
But this is About the Mid peak panel Fix... at least most of it....had to try find away to get this speaker working ... so I could use them...
Look at the pic of the 3 screws...See the plastic insert type peace…. on the one in the middle ....you well need 8 per speaker....pull the cloths down so you can get to the panels....pull the 8 screws out.....put the 8 inserts in the back holes... be sure they stay as you screw the panels back on...
Yes you could put any thing between the panels an the frame to change the sound of the peak...but most things I tried changed the panels sound to much....but this keeps the panels sounding the same ….just with much less mid peak....have fun with Acoustat
Back in the 90s when I got my first pr of Acoustat Spectra 11, I lov the sound...
But after about 30min...I got a head headaches....Wow that sucket….so move on to the 1+1,2+2s....
Then got pr off CL...2015...Still had the peak in the mids others have found an
Bolserst posted about this...So now we know.. it not just me that hearts the mid peak.
Spectra 11 have been showing up on CL at fair prices ...so now I have pic up 5pr ....All the Bias have been low on all 5 pr ...an thats lead to minny post here about fixing the bias part of the Spectra11....so you must get 85-90 volts at the end of the 500mg ohm panels feeder resistor right were it feeds the wire to the panel!..... to get full output of the panels an match the bass driver output so you can hear how great these speakers can sound.
But this is About the Mid peak panel Fix... at least most of it....had to try find away to get this speaker working ... so I could use them...
Look at the pic of the 3 screws...See the plastic insert type peace…. on the one in the middle ....you well need 8 per speaker....pull the cloths down so you can get to the panels....pull the 8 screws out.....put the 8 inserts in the back holes... be sure they stay as you screw the panels back on...
Yes you could put any thing between the panels an the frame to change the sound of the peak...but most things I tried changed the panels sound to much....but this keeps the panels sounding the same ….just with much less mid peak....have fun with Acoustat
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The screws are perpendicular to and over an inch from the conductive coating on the mylar. I can't see them affecting the operation of the diaphragm at the frequencies involved, but OCICBW. Isolating the panels with spacers, however, is almost sure to change the sound in some way due to the change in how it imparts energy to the frame. It would be interesting to try very light springs or similar suspension methods.
I well guess at why this works!...The t-washer is made of the same type of plastic. An works means sound like only the peak is lowered...Not the sound has changed.....your springs would work but...would add some ringing to the sound....I would like to get the best sound an make it a ezy fix...
All so I have done frame work with ML top of the panels ...an found the same with the spectra 11...the top frame peace can also make a peak...I have added cloth ….but it was to much...I have lowered the panels about 1/2"
from the top...In the end it the peak that has to go...for me it was a fiscal hearing pain....I could not play the speakers..
You will find much better sound. The socks muffle the sound big time, been running my Spectra 22 naked for years. Best upgrade for Acoustats, costs nothing. Long Live Acoustats!
Tried it and indeed more detail (and mint looking panels
), but as was expected tonal balance shifted even more towards the highs. Will first upgrade the bias supply and high pass caps + lower dcr coil on woofer + check bias voltages + stuff some felt between the panels and frames. I love the wide soundstage and microdetail, but even with loudness boost they are hurting my ears after short listening (in a highly reflective room, that is)...
Had a lot of Acoustats pairs over the last 35 years.....Always thought the panels sounded better with the covers off....But here lately I have found the stock or any cloth covering over the panels helps stop the panels mylar from ringing.
Thats right, I feel that you can get the best high frequencies with the cloth on!...just took 30 years to get back to it....Now this is with all the Panels interfaces bias re-worked with new diodes an caps ….85-90 volts at the end of the 500meg ohm res. (the end of the res. that feeds the wire bias to the panels)….85-90 volts there = close 5k....All the interfaces, I have had about 20 are more pair .. I have found are low an need to be re-worked to day.
Audio got love the trip....also this is just one mans o-pine about the cloth...
The bias,with out the 5k bias you don't get full output of the panels, an can stress all the parts in the interfaces...an can kill transfourmers.
Low cost to pay for the best sound out of one of the best Vintage ESLs ever made.
Thats right, I feel that you can get the best high frequencies with the cloth on!...just took 30 years to get back to it....Now this is with all the Panels interfaces bias re-worked with new diodes an caps ….85-90 volts at the end of the 500meg ohm res. (the end of the res. that feeds the wire bias to the panels)….85-90 volts there = close 5k....All the interfaces, I have had about 20 are more pair .. I have found are low an need to be re-worked to day.
Audio got love the trip....also this is just one mans o-pine about the cloth...
The bias,with out the 5k bias you don't get full output of the panels, an can stress all the parts in the interfaces...an can kill transfourmers.
Low cost to pay for the best sound out of one of the best Vintage ESLs ever made.
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Very surprising to hear the responses.
They always sound muffled to me with the cloth on. Maybe spandex or other thin cloth might help with any ringing without dulling the highs, but the stock socks are thick and I can’t imagine them improving the sound. Are you guys suggesting that the highs from acoustat panels are harsh or exaggerated and need to be tamed by thick fabric?
They always sound muffled to me with the cloth on. Maybe spandex or other thin cloth might help with any ringing without dulling the highs, but the stock socks are thick and I can’t imagine them improving the sound. Are you guys suggesting that the highs from acoustat panels are harsh or exaggerated and need to be tamed by thick fabric?
I have Model 3 with stock socks and Monitor 3 naked. I can tell you from my experience the Model 3 sounds brighter than the Monitor 3 with DD Otls. The difference is swamped by the interface vs the Otls to such an extent as to render it moot. However I don't think I'd want to use the Model 3 without the socks after comparing with the naked Monitor 3. I don't know how the Monitor 3 would sound with socks as I got them as is without. But naked/ringing or not, the Monitor 3 is King. That's for sure. They sound very clean and articulate over the entire spectrum so unless the socks were transparent and for cosmetic purposes only, I really can't see an improvement; but I was wrong once before so anything is possible
I did purchase grill cloth for them a few years ago but the seamstress I hired to make them left a bit to be desired so I left them as is. I actually think they look great this way.
I did purchase grill cloth for them a few years ago but the seamstress I hired to make them left a bit to be desired so I left them as is. I actually think they look great this way.
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Discopete...
"But naked/ringing or not, the Monitor 3 is King. That's for sure. They sound very clean and articulate over the entire spectrum so unless the socks were transparent and for cosmetic purposes only, I really can't see an improvement; but I was wrong once before so anything is possible"
To my ears the old Xs I had, with the panels bottoms, set right on the floor
An driven with the Servo OTL tube amps...the top end sound rolled off...So you maybe right that the ringing is with the interfaces..i can see that...thanks for your input on this
As for the high frequencies of the Acoustat panels being driven with the MK 121 interfaces....never sounded right to my ears...but having had the Stock Acoustat Servo tube amps for only a short time as my first Acoustat...thats the sound my ears may have got hooket on?....Even with the grill cloth on are off...they still don't sound as good as I wont them too...I gess this comes from living with Martin Logans CLs panels..an hearing better...Sweeter top end, with the one setup transfourmer….It lot ezer for me to say this now that I have a great Cary CAD 120smk2 with the power to drive all my ESLs with
"But naked/ringing or not, the Monitor 3 is King. That's for sure. They sound very clean and articulate over the entire spectrum so unless the socks were transparent and for cosmetic purposes only, I really can't see an improvement; but I was wrong once before so anything is possible"
To my ears the old Xs I had, with the panels bottoms, set right on the floor
An driven with the Servo OTL tube amps...the top end sound rolled off...So you maybe right that the ringing is with the interfaces..i can see that...thanks for your input on this
As for the high frequencies of the Acoustat panels being driven with the MK 121 interfaces....never sounded right to my ears...but having had the Stock Acoustat Servo tube amps for only a short time as my first Acoustat...thats the sound my ears may have got hooket on?....Even with the grill cloth on are off...they still don't sound as good as I wont them too...I gess this comes from living with Martin Logans CLs panels..an hearing better...Sweeter top end, with the one setup transfourmer….It lot ezer for me to say this now that I have a great Cary CAD 120smk2 with the power to drive all my ESLs with
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As it is very simple to do, I have pulled up the socks on my Spectra22 and done some listening. Calling the sound “muffled” is perhaps a little strong, but you definitely lose some details and high end “air” and extension.
But you do gain something I think, less directionality. With the socks off, the highs and upper midrange are very directional (even my Spectra series with the reduced panel size for highs). The speakers are more obvious as a sound source, and I am constantly messing with toe in to get a convincing sound stage. With the socks back up, the speakers are less obvious as a sound source, they disappear better and soundstage better.
Not sure exactly why this is, and need to do more listening. But it appears to me that there are advantages and disadvantages to running with the socks, and it comes down to personal preference.
Would acoustically thinner socks provide the best of both worlds?
But you do gain something I think, less directionality. With the socks off, the highs and upper midrange are very directional (even my Spectra series with the reduced panel size for highs). The speakers are more obvious as a sound source, and I am constantly messing with toe in to get a convincing sound stage. With the socks back up, the speakers are less obvious as a sound source, they disappear better and soundstage better.
Not sure exactly why this is, and need to do more listening. But it appears to me that there are advantages and disadvantages to running with the socks, and it comes down to personal preference.
Would acoustically thinner socks provide the best of both worlds?
Well I know what you mean. I have had and compared the original Xs with the Monitor 3. Raising them off the floor corrects the top end roll off pretty well; if not, satisfactorily imo. Also, the original Xs were mounted virtually in a box. No wonder the exaggerated mid and bottom end, right? The Monitor 3 are very ruler flat in FR. I've listened to ML and am not impressed with their over all presentation. They sound thin with boomy bottom end. Not much bottom end definition there. The Acoustats have no lack of bottom end definition at all. What they lack at the bottom is extension which is where the subs come in, at around 35-40hz. Perfect. Also, there are upgrades for the OTLs.
It's easy to fault the improvement you hear in saying they are more directional. Rest assured it is an improvement. Doesn't matter what the design is, dynamic or planar or esl. The more precisely you position yourself in the sweet spot, the better they'll sound, period. That the ESLs are more pronounced in this regard is testament to their superiority, not the other way round. They are "head in a vice" in comparison to themselves, not to other speakers. Flat panels need to be toed out, not in or directly at your ears. They should be facing about 10 ft. behind your listening position. In my case that's about 15deg. toed out since I sit about 13ft. away and the speakers are about 8ft. apart, leaning back 3deg. It took around 3 years to arrive at this set up after changing them countless times. It was when I decided to be brave and toe them way out that all of a sudden it became obvious. It's still a very precise geometry. Before I did this I thought I was hearing them at their intended best; not so. The way they are now, a bit more in or out and they lose impact and imaging. So the sweet spot is actually a bit larger than you are probably experiencing right now. And in fact, there is a more pronounced change moving your head forward or back than from side to side within about a 12 inch circumference.
Sounds Right...I think the Servos tube amp on your speakers has got be the Best sound that can be had out of the Acoustat panels...the Martin logan CLS for me just give the sound the Acoustat cant with the interfaces...but your right the ML are lacking...an so the Acoustats….An Sound lab...they seme to all be lacking some thing I like...poor me, I have had an still have great sound an fun with all these old ESL...to day I been running my Apogee centar Minors An Slant 6..24"ribbons with 61/2 drivers....95% of the ESLs sound..
with Great rich mid tone...lot fun...
Thanks for all an any info on getting better, different, sound out of any ESLs