So the story Begins 2 or 3 years ago, when a new friend, Nick introduced me to a fellow hifi enthusiast pal of his. I met the the guy and he definitely had the bug and had it bad. He brought me some gear to check out which I did free of charge. ( i think i cleaned a few switches and pots with DE-oxit) He mentioned having bought and Acrosound Ultralinear 2 at an estate sale with the matching Dynakit mono preamp and a Giant BOZAK speaker. At that time I mentioned that should he decide to sell the amp that I would like to make a serious offer. He is after all a solid state type of guy... Several months later I got a call and he indicated that the time may be right to make that serious offer. I took cash and came home with this beautiful Acrosound, unrestored and working, and in beautiful shape for its age.
I Had some Idea of what I was getting my self into, I own a magazine somewhere where this amp was explained and bragged about by its designers. I knew it was Top of the line tube gear, and I had to have it. I got to work doing as much research as I could about the amp and the options for bringing it up to date. It didn't take long to find the info Brice has posted on his set. I sent A PM to Brice and he had a set of extra prototype boards available for me to purchase. I Immediately went to work ordering the best parts I could afford, to rebuild these unique monoblock amps. Somewhere in the mean time I bought another on Ebay for within $5 of what I paid for the first. The other one is so damn ugly that it broke my camera, hence: No pictures of it!
One cool feature of this Amplifier design is that it only uses 2 coupling caps. I do not like to argue, so fewer coupling caps is a better choice, fewer things to argue about. I chose the typical low end caps to start with, and ordered a few sets of audiophile types to roll in when the mood suits. I honestly doubt that they will have any affect on the performance of this lovely sounding amplifier.
I used some special reserve old production 9 pin triodes for these. I pulled a set of Telefunken Ribbed plate 12AX7s and a pair of Raytheon Blackplate 12AU7s from my private stash. Given the feedback loop around the entire amp, I have my doubts that any measured performance difference could be found between good tubes of the same type. I'm just showing off... The power tubes are Russian 6550s from Jim McShane. Rectifier is a Vintage Mullard 5AR5 Bypassed with Diodes. Again, just showing off.
I may be trying to find another set to restore for a club member friend of mine who has expressed interest in owning a pair. These are the biggest and by far the most powerful tube amps I've ever owned. They are a definite step up from the HH Scott 299D which was my main amp prior to these. I need to find a preamp that I am in love with and the conclusion that I'm coming to is that I may need to build that preamp. Perhaps more on that later... As for these Acrosounds, they just drive rich beautiful and dynamic sound from top to bottom and at as loud of a volume as you can stand to listen at, with headroom. I am very happy with the result.
I Had some Idea of what I was getting my self into, I own a magazine somewhere where this amp was explained and bragged about by its designers. I knew it was Top of the line tube gear, and I had to have it. I got to work doing as much research as I could about the amp and the options for bringing it up to date. It didn't take long to find the info Brice has posted on his set. I sent A PM to Brice and he had a set of extra prototype boards available for me to purchase. I Immediately went to work ordering the best parts I could afford, to rebuild these unique monoblock amps. Somewhere in the mean time I bought another on Ebay for within $5 of what I paid for the first. The other one is so damn ugly that it broke my camera, hence: No pictures of it!
One cool feature of this Amplifier design is that it only uses 2 coupling caps. I do not like to argue, so fewer coupling caps is a better choice, fewer things to argue about. I chose the typical low end caps to start with, and ordered a few sets of audiophile types to roll in when the mood suits. I honestly doubt that they will have any affect on the performance of this lovely sounding amplifier.
I used some special reserve old production 9 pin triodes for these. I pulled a set of Telefunken Ribbed plate 12AX7s and a pair of Raytheon Blackplate 12AU7s from my private stash. Given the feedback loop around the entire amp, I have my doubts that any measured performance difference could be found between good tubes of the same type. I'm just showing off... The power tubes are Russian 6550s from Jim McShane. Rectifier is a Vintage Mullard 5AR5 Bypassed with Diodes. Again, just showing off.
I may be trying to find another set to restore for a club member friend of mine who has expressed interest in owning a pair. These are the biggest and by far the most powerful tube amps I've ever owned. They are a definite step up from the HH Scott 299D which was my main amp prior to these. I need to find a preamp that I am in love with and the conclusion that I'm coming to is that I may need to build that preamp. Perhaps more on that later... As for these Acrosounds, they just drive rich beautiful and dynamic sound from top to bottom and at as loud of a volume as you can stand to listen at, with headroom. I am very happy with the result.
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