Why does my new tube amp and preamp sound so bad?


Hi: I am brand new to audiogon but I would appreciate any ideas you folks may have. I am a seasoned audiophile with only SS experience. I have wanted to try the "tube" sound for awhile but have just now been able to afford it so I put together a new tube based system along side of my SS. I purchased a used set of Klipsch La Scalas and restored them and powered them via my Adcom amp and preamp. The speakers sounded excellent, great bass! All right, next step after much internet research, but without hearing, I purchased a new Cary Rocket 88R amp and a AES (Cary)AE-3 DJH preamp. There are no Cary dealers within 200 miles of where I live (I know dumb mistake!)Hooked the system up and it sounds terrible. Well I thought the tubes just needed breaking in. After 100 hours no better. The sound lacks any bass and it is very "tinney". It sounds as if a low frequency roll-off filter is present. I contacted Cary and they said substitute the AE-3 for my Adcom preamp. I did and there was an immediate improvement. Cary had me ship the preamp back and they checked it out and could not find anything wrong. I put it back into the system with the same results. Does anybody have any ideas? Could tube rolling be the answer? I have tried different interconnects which made no difference. With all things being the same the Cary preamp sounds terrrible when compared to the SS Adcom. I am having a hard time believing it is natural that the 15 year old Adcom smokes the Cary. I am a fairly competent electrical engineer and I believe the tube setup (bias) is correct. I would appreciate any help. Thanks, Larry K.
lkitchell
Hi Larry, i also have a Cary pre, slp98, when i first put it into the system i had the same result as you, no bass and thin sounding.Not familiar with your model, but after reading the manual, i realised my pre is phase inverting, the manual recommends reversing the polarity of the speaker cable at the speaker end, done this and solved the problem, now sounds full with good bass.
Hope this helps
Rob.
If you are encouraged enough to go further with a complete tube system, my advice would be to put aside both preamps and find one with tube rectification. A used Cary SLP90, 94, or, 98 would be an excellent choice if you want to keep it in the Cary family. Do not under estimate the older SLP90. Next step is to spare no expense on the preamp tubes. You also can greatly improve the amp's sound by doing the same with the input tubes. Since you already like the amp, this could be your last step. My experience has been that most modern small signal tubes sound mediocre when compared with the NOS stuff.
Any time a new piece of gear or a change in gear speaker's might have to be reposition into or back towards wall. Also might help spreading them apart or closer together.This is why I made the suggestion. Anyway like chicken soup it couldn't hurt.
The La Scala's (we own them as well) sound completely different depending upon placement. Even when swapping between the two different tube amps that we have, I have to adjust the speakers to optimize the sound. Still, we use an active sub, as 53Hz is not so low. Try moving the speakers around a bit, experiment with the spacing & toe-in. We have not toed ours in at all, for example.

I also think that NOS tubes add a richness and depth that most modern production tubes (especially preamp tubes) cannot match. Tinny and thin is exactly the way I would describe many of the current tubes.

Sounds like the speaker cable switch will make a big improvement as well, as Rob mentioned above.

Best of luck,
Howard
I was thinking the same thing as Rob and Howard. You might have a polarity issue. Easy solution to try out.