Acoustat 2+2 C Mod Repair

[kgreen6]

Hi, trying to find out is there any place in San Diego or close by that can do the C Mod repair or send me photos of exactly what needs to be done? Any help would work. I am pretty handy and have a local audio repair person but just want to see if this is something that I can do myself.

 

[AcoustatAnswerMan]

Hi, trying to find out is there any place in San Diego or close by that can do the C Mod repair or send me photos of exactly what needs to be done? Any help would work. I am pretty handy and have a local audio repair person but just want to see if this is something that I can do myself.

A complete set of instructions for doing the "C-Mod" is available on the website www.audiocircuit.com. Just go to the Acoustat section and it should be easy to find. The procedure includes instructions for doing the modification to several different variations of the basic MK-121 interface. The work to be done is relatively simple, and should be an easy task for anyone with basic electronic repair skills. The parts required are also easy to obtain.

 

[hella356]

Yes, it's not too difficult. I've seen differing opinions concerning the best make/model of capacitors to use, but any decent parts should yield a nice improvement.

 

[AcoustatAnswerMan]

A complete set of instructions for doing the "C-Mod" is available on the website www.audiocircuit.com. Just go to the Acoustat section and it should be easy to find. The procedure includes instructions for doing the modification to several different variations of the basic MK-121 interface. The work to be done is relatively simple, and should be an easy task for anyone with basic electronic repair skills. The parts required are also easy to obtain.

I just checked the audiocircuit website, and although the C-Mod instructions are still listed, clicking on the link yields a 'page not found' message. I will post the instructions here within the next day or so.

 

[tyu]

Acoustat mod

Acoustat........Some say the 1+1 is the best older type....becase it flat an only 9" wide!
So i just made a 3ea 9" panels wide speaker..........Flat ..........65" tall....
I have been moding the 121 for 25 years...........outboard you set bias....4-7K......... an put a biger 1ohm....... like a 50 watt on the bass tranfo,after all it keeps the Killer heat out of the tranfo when driveing hard.....best thing anyone can do with Stock Acoustats........An the sound KILLS all other speakers i have had an have now!.......Sweet sound....
Only thing i see bad about the Acoustats.......stop the need to look,own any other speaker....Jim had the cost down...in just parts the panels could be maid for less than $10. US........We all are Vary Lucky to have Acoustat....
Just some info on mods i have got from others........
Thanks to all for an any info on ESLs....................
Long live Acoustats

 

[john65b]

tyu - I just finished refurbing a Spectra 22 and it really surprised me. Sounds much cleaner (and no beaming) in the HF than the Model 3, and has most of the bass. Thinking of adding two more regular 9" panels and a bass tranny out of a MK-121 to the setup - this should be even better than my Apogee Duetta Signatures.

 

[tyu]

Yes i saw your post on the Spectra 22 ............i get know beaming with the flat 3ea 9" panels......Bass to die for....but the bias is were there is work to be done.....an res. that drive the panels upgread.........HUNTINGTON ELECTRIC, INC. 1 P.O. BOX 366 1 HUNTINGTON, IN 46750 1 (260) 356-0756 1 Resistors, Axial, Power, Oval, Wirewound, Brake, Grid, Precision, Edge Wound, and Neutral Grounding
Jim got the res HEI FST-50 50K ohm in my 121 Sweet sounding res..........be good to your self an get new...an get a self setup bias set for all an any ESLs...
If i wont more mid-bass i just turn the bias down a littel....if i need sweeter highs just add a littel more bias......if it rainy out...i can get vary good sound
.........only Spectra i have owned is the 11s
Spectra is a great setup.........why....one, it flat!........with a littel delay makes a crve.
have fun........

 

[AcoustatAnswerMan]

I just checked the audiocircuit website, and although the C-Mod instructions are still listed, clicking on the link yields a 'page not found' message. I will post the instructions here within the next day or so.

Attached is a .pdf file with instructions, schematics, and suggested sources for parts for doing the C-Mod to any of the MK-121 variations. This modification may be done even if you do not have the Medallion transformers.

 

[tyu]

Thank you sir...........for all the help on one of the Best ESL speakers ever made!
Long live Acoustat ESLs