Acoustat Answer Man is here

[RobertS61]

Originally Posted by MrAcoustat

Yes there size & weight 228 pounds each mono blocks recaping these baby's is not cheap and these amps are 25 years old so they will need servicing pretty soon IF it as never been done, but they are GREAT amps. André

Recapping is not so expensive if you can find the right large can capacitors for their powersupply's and you can perform it yourself as you probably can.
I've done this with a couple of Threshold SA/1's, Levinson ML-2's and dozens of preamps.
Frontend of your KRS-100: axials from BC Components, radials from Panasonic FM or FC Series (Digikey).
Powersupply: Digikey also and just look for the same or higher voltage and the right size. You're probably safe with 60 Volts or more with a rail that has to supply the 100 Watts at 8 ohms (30 Volts output).
I would't care if it is Mallory, Cornell Dubilier or United Chemicon (former Sprague).
With the KRS-100 you should pay extra attention to the outputrelays because they tend to contaminate/oxidize.

[tyu]

I just did a recap on a KSA150 an a KST 100 an the Big power caps did not need replacing,just all the small caps are a must....
I had krell recap a KSA 250..$2k an thay did not put new big power caps in...big caps dont dryout like the cooket small caps on the boards....one thing for sure these great amps sound a LOT better with new caps!....
An get the bias just right better sound than when thay were new..
But as for the Sound of the Krell amps on Acoutats ESL....i dont care for the sound, My Apogees are what i have the Krell for.. the Apogee were made for the sound of the older krell amps....well best i have found, sweet like tubes....littel to dark for my ESL..

[RobertS61]

Originally Posted by tyu

I just did a recap on a KSA150 an a KST 100 an the Big power caps did not need replacing,just all the small caps are a must....
I had krell recap a KSA 250..$2k an thay did not put new big power caps in...big caps dont dryout like the cooket small caps on the boards....one thing for sure these great amps sound a LOT better with new caps!....
An get the bias just right better sound than when thay were new..
But as for the Sound of the Krell amps on Acoutats ESL....i dont care for the sound, My Apogees are what i have the Krell for.. the Apogee were made for the sound of the older krell amps....well best i have found, sweet like tubes....littel to dark for my ESL..

Especially those darkred ERO's that dried out in a few years according to my Krell tech. You probably right about the big cans but Nelson Pass and Jon Soderbergh perform a recap with Thresholds anyway when they have a service life of more the 20/25 years. So I just complied with my SA/1's and ML-2's.
If you only have to recap the small lytics in the KRS-100 a couple of hundred dollars would be the max then.

[tyu]

....Puting new big caps is not bad for sure....i test the Big caps for leakedg...an thay all tested good...Krell wonted for the Big Caps in the KST... the small A/B amp...i think the caps are 60v 13k uf ea....almost $400.US ea that $1600 for 60v caps.....I thought it was a Joke....thay did not think it was funny.. i can get the same cap....$46........Thay wonted $350.US for the KSTs on-off switch... $63. i paid.....good luck to Krell...Dans gone..

[RobertS61]

Originally Posted by tyu

....Puting new big caps is not bad for sure....i test the Big caps for leakedg...an thay all tested good...Krell wonted for the Big Caps in the KST... the small A/B amp...i think the caps are 60v 13k uf ea....almost $400.US ea that $1600 for 60v caps.....I thought it was a Joke....thay did not think it was funny.. i can get the same cap....$46........Thay wonted $350.US for the KSTs on-off switch... $63. i paid.....good luck to Krell...Dans gone..

Yeah Krell rips you off. I have the same experience with them.
Needed two switches for a Krell KRS-2 preamp and paid four times as much as the same part at Digikey.

[ktuuri]

Andre sorry to hear you lost some of your picture.
Just keep putting them here, for Backup! :O)

Nice Pics!

[MrAcoustat]

Originally Posted by DeltaStar

Meat Popsicle, How loud are you trying to play those 3's , I get 85DB with ease using a lowball amp the Hafler 220 rated 100wpc, and thats at sitting 60' from them, and thats way way to loud for me at most time's. maybe the room is to small for them, they need alota space to breathe in, or they suck the amp dry cause they can't make sound in close qaurters.

Please don't forget that where talking about here a $1,000.00 500 watts mono block this is no Krell - Mark Levinson - Classé - Jeff Rowland - this is Emotiva you get what you pay for this is a budget amp for budget speakers Acoustat's deserve better then that sorry.

[RobertS61]

Originally Posted by Meat Popsicle

Hi all just a brief intro. I recently bought a pair of acoustat Model 3's for $400 that have never been opened up or modified . They work great and sound fantastic. They are definitely keepers! I've already contacted Roy Esposito and will have my interfaces done, including both the C and the Air mods in the Spring.

I'm running Emotiva XPA-1 Monoblocks 500 watts into 8 ohms, 1000 into 4. Even they run out of juice on the Acoustats. I'm not quite sure if the protection is kicking the amps off due to too much current out, or not enough in, but they do trip relatively early. My theory is they see the low impedance of the Acoustats as a short circuit and bail to save themselves.

I'm wondering if these autoformers might be the solution, but $450 is a bit too dear for me to potentially toss down the rat hole. I think instead I'm going to invest in a decent subwoofer to take some of the burden off both the amps and the speakers. Ther amps seem to kick off mostly during the loud bass passages.

I'll be lurking and learning, and hopefully not putting my foot in my mouth (too often). Carry on!

First, I've had Threshold SA/1's on them graced with meters so I could observe their behaviour quite well. Acoustat's suck current at the higher frequencies not at the lower ones. Every time a female singer raised her voice considerably the meters went to the right upper corner when playing at loud levels of course.
Read Nelson Pass articles about lot's of negative feedback and the lack of damping factor at the upper frequencies when driving a electrostatic speakers with their 1 or even lower Ohmic values in the highs.
Second, I have a pretty solid Japanese poweramp which delivers 240 Watts at 8 Ohm and almost 400 watts at 4 Ohm loads (Yamaha M2). Nevertheless it's no match for my 25 Watts Levinson ML-2's (at 8 Ohm) when driving my Acoustat's.
Amplifier performance is not only about their powerrating in Watts. The ability to absorb energy back from the speakers, to deal with phase-angles and difficult loads (current output) is more important in my opinion.

[MrAcoustat]

Hi this is the amplifier that drove ALL of my Acoustat's from 1988 to 2000 - 1+1s - 2+2s - Spectra 22s - Spectra 33s - the Classé DR3-VHC 45 watts per channel pure class A very high current amplifier and it did the job very well.

[Meat Popsicle]

Mr Acoustat, I beg you to remember some of us live in the workaday world, have real budgets, and can only afford so much. Just because I don't have schmancy amp this or that or granite bases and iron frames on my speakers, doesn't mean I dont enjoy this hobby one bit less than you. I came here to discuss getting the most out of my 20 some odd year 400 dollar speakers that I bought because they were what I could afford! I joined diy audio because you're here and others much more knowledgeable than I also. I was hoping to discover some inexpensive ways to improve my system and maybe learn a little more about the actual electronics making up my components. I resent your dismissive and disrespectful tone toward my choice of amplifiers based on their cost. They're damn fine amps for the price, a way for me to enjoy music on a higher level on my budget, and you can take your overpriced snob gear and shove it where the sun doesn't shine if you are going to scoff at those of us unfortunate enough not to be able to afford this HOBBY at your level. I could be wrong, but I'll bet you have never even heard Emotiva XPA-1 amps. If you haven't, I suggest you look at their multiple published pages of specs and examine their build quality, order some for a 30 day FREE trial listen to them, and then tell me they're not worth every penny of their price!