sns109

Yeah, I did all the mods myself. While I can solder, replacing parts and building kits is the extent of my abilities. I could measure DCR on choke, however, where would I take measurement from? No schematic, pretty simple circuit. I will get pictures to you tomorrow. I only thought silver would help by thinning out bass to some extent, I agree silver has much more affect on highs. I appreciate the offer to help, hopefully something can be done to improve amp. Again, I'll get pictures out to you tomorrow.

BTW, my Klipschorns are modded, only stock piece is bass cabinet. Crites cast frame woofer, John Allen A55g mid, B&C DE120 tweeter, Volti mid horn, tweeter mounted on custom baffle in line with mid driver, Duelund silk/oil tin plate copper internal wiring, Furutech wire to woofer, Vampire binding posts, upgraded tag strip, Jupiter VT and Audyn True Copper Max, Duelund Silver bypass caps in Crites AA crossover with diode protection circuit removed. Result is much more natural timbre, greater transparency, resolution, bigger sound stage, life size images, dynamics wide open. I never like to say never, but it is likely these are last speakers I'll ever have in main system.

Thanks Jeffrey, You make a lot of sense. All caps electrolytic in this amp with exception of coupling cap. I replaced the Russian cap with the Vcap, as good a result as I could have expected, opened up top end, much better tonal balance now. Also, higher resolution, blacker background thing with the Vcap vs. Russian. The increased detail also distracts my attention from bass. The power supply consists of four 100uf Vishay/BC component caps and one Epcos/TDK 600uf cap, also has choke. This is for each channel. I have no doubt silver content in wire would help with bass, assume this is all copper. I may change out wire if I decide to keep amp. This is my first foray into relatively low power SET with Klipschorn. You are correct in regard to crossover sucking power, the impedance curve is a bear from aprox. 32 to 225 hz. I hear macro dynamic compression in more complex passages, doubt this amp can ever overcome that limitation. The 845 amps are simply beautiful with the Klipschorns, absolutely no sins of commission. I've tuned my entire system for over two years for perfect compatibility with the 845 amps, quite possible I don't find a sympathetic alternative amp. At this point, I may have to go with a push pull if I stay with tubes, otherwise the class A solid state or the new GAN fet class D's if I continue to hear good things.

The GAN (gallium nitride) FET class D amps I speak of are a rather new technology for audio. Technics SE-R1, and at a lower price level, the AGD Audion, LSA Electronics Voyager, Java Hifi and soon to come GAN amps from NuPrime, Nuforce and a few others. These FET's switch at much higher speed, supposedly eliminating some of the liabilities of older devices. Based on initial reviews the GAN amps sound less dry and sterile than other class D. If true, could be a game changer for class D.

The specific amp I acquired is Tube Fantasy, individual in China builds these from his home. I purchased these based on the experience of some trusted users over on Audiogon, they've successfully used this guy's amps on Zu speakers. While I know Zu speakers present a different load to the amplifier, I purchased based on build quality. Really rather funny, but the Chinese builder writes with better English grammar than many Americans. He appears to be knowledgeable and honest in my conversations with him. Also, having the amps in hand, they are quality built. I still believe my bass issues come from the rather difficult load Klipschorns present in bass. I suspect I'll need a 4ohm tap with any SET amp other than 845 to satisfy my bass needs. The 845 amps simply muscle themselves past this liability, assuming their single taps are 8ohm. BTW, 845's are Coincident Turbo 845 SE and Art Audio Carissa Signature. Running Coincident Statement line stage. Being new to 300b amps. Is 1000uf of capacitance in 300b power supply (my 845's have tons more capacitance) sufficient to provide quality bass? Drive and micro and macro dynamics seem pretty nice, although not to the level of my 845's.

I have to say I'm extremely particular when it comes to bass, once I hear a less than articulate bass my attention is forever distracted by it. Many other listeners seem not to be bothered by bass that bothers me. My 300b is a cottage built unit, guy builds them in batches of ten, power supply has 1000uf capacitance of Vishay/BC components, hand turned output transformers which I'm assuming don't have 4ohm tap available. I'm using NOS Mullard F32 rectifiers, NOS RCA long grey plate 12au7, NOS Amperex Bugle Boy 6267 and Shuguang Treasure Black Bottle 300b. The Shuguang are reportedly at the lower end of the best in the articulate family of 300b tubes. I previously built the Latino Dynaco clone amp. Granted it was in a different system, but I was never impressed with resolution of the unit in comparison with my 845's. And that was with some better quality parts than supplied with kit and top line tubes. I've owned several push pulls over the years, EL34 my favorite tubes in these, while nice I still prefer SET sound. I did own Wright Sound 2A3 monoblocks many years ago, I was using those with Omega and EL Jordan single driver speakers. My recollection was they did some very special things in the mids, couldn't tell much about bass and highs as they are rolled in single driver speakers. I did obtain greater amounts of bass with these speakers with some Cary SLM 100 and conrad Johnson MV-55 I was running at the time. I'm afraid I wouldn't be satisfied with 2A3 bass, the 845 amps spoil me with great amount of drive, articulation, micro and macro dynamics. I find 845 and Klipshorns magical combo, life like presentation. If I didn't have the heat problem these would be my final solution. I've heard similar reactions to many long term reviews of class D amps. I'm just wondering if the new GaNfets are an advancement? Thanks guys, keep coming with ideas and possible solutions. Scott

Hello, this is my first post, although visit these forums often. I recently acquired a 300B SET amp to audition as a summer replacement for my two 845 SET amps which are space heaters. Both of my 845 amps have wonderful tonal balance, articulate bass, reasonably extended highs, fully involving mid range. This is the third summer replacement amp auditioned, the first two class a/b solid state, both nice enough but lacking the palpable, meat on the bones quality of my SETs. The 300B has a nice palpable mid range, highs are a bit rolled which I can probably live with. The big issue for me is lack of articulation in bass, this along with more rolled off highs gives a rather dark presentation. Overly loose, warm bass has always bothered me, articulate bass is an absolute requirement for me. I suspect a 300b amp may be inherently unsuitable for me. Looking at the impedance curve of Klipschorns, below 8 ohms between aprox. 40hz to 225hz along with steep impedance curve is too much for this amp. No separate taps on amp, assuming 8 ohm on non-separate tap tube amp. It seems the 845 SETs with their 8 ohm taps overcome this limitation, the 300b tube can't handle it. I'm in midst of one mod which may or may not address bass issue in that I replaced the Russian K40Y9 coupling caps with VH Audio Vcaps. Assuming this 300b isn't satisfactory for me, what amps do you guys think would work for me? At this point I'm planning on auditioning First Watt J2 or F7, another intriguing option would be AGD Audion GaN Tube monoblocks, class D amplifier that supposedly replicates SET amp sound to quite a degree. The class A solid state amps will also be hot, albeit not to the same degree as the 845's. Any other class D amps close to SET sound?