0 Members and 1 Guest are viewing this topic. Read 16727 times.
My friend bought an old KT 550, He brought it over for me to hear , it had some problems...so.. I took it to my friend Vinny,a great tube repair guy on Long Island, what came back after he rebuilt it with new caps,is one of the best amps I ever heard in my LIFE! Weighs about 60 or 70 pounds, 55 watts , huge transformers.The musicians came out of my speakers and decided to play in my room last nightI was dancing and swearing and sweating it was friggin great.Pure power and music, throbbing live music that you could listen to forever, your pulse changes with the music, it is sick, makes a dancer out of a wallflower I have this one disc of Michael Brook"Cobalt Blue" I would listen to this and it would lull me to sleep sometimes, last night it was another world, the music popped out of the speakers ,, huge, every note gripping and important and necessary I am still excitedSorry to gush, but I gotta tell someone
The musicians came out of my speakers and decided to play in my room last nightI was dancing and swearing and sweating it was friggin great.
Woo Hoo
BuddyTubes rule!! Dogs Drool!!
The Lafayette KT-550 stereo amp is quite similar to the Harman-Kardon Citation power amp, both were all-out designs by the one and only Stu Hegeman. Both are perhaps one slight step superior to the Fisher 500c with its 7591's. The primary difference between the KT-550 and Citation II, I think the Citation II was the later improved model a couple of years later, made using ultra-wide bandwidth video tubes for the input gain and driver stages (12BY7's) and using the just newly released KT-88's by GEC of England, instead of the 7027's. The 7027 had a 25 watt Pd. versus the 35 watt Pd of the KT-88; later the 7027A tubes eventually matched the 6550 / KT-88 Pd at 35 Watts of Plate dissipation per tube, but using those in the KT-550 would not improve any characteristic of the KT-550.So, the pair of 7027's produced 50 wpc in the KT-550, while the KT-88's in the Citation II managed 60 wpc. and perhaps even a little bit more. In both amplifiers the output transformers were very nearly the same, the power transformer however, appears to be somewhat smaller in size in the Lafayette amp limiting the power to the original 7027 levels. Both the Citation II and the Lafayette KT-550 are at their sonic best when pricey Polypropylene or Teflon coupling caps are installed to let their full clarity and tube transparency through.Of course, the vintage stereo amp, circa 1960 to die for is the Acrosound Stereo 120 with original GEC KT-77's in it.... It would be interesting to compare a modded KT-550, against a souped up, rebuilt Citation II against an Acrosound Stereo 120 ( or its identical twin - the Realistic HK-210 ) all with new pricey caps and Hexfred diodes. All three are power-house amps, yes. Nice sounding amps all of them, but hither, still using the flawed push-pull topology... ultralinear on the screens and etc,. so none of them possesses the true sonic purity of a really well designed SET Amp.--Steven L. Bender, Designer of Vintage Audio Equipment