Tube amps for Horn speakers.......

Hello to all that read this and try to help me. I come to this website everyday and see whats going on but am afraid to ask questions as for I am a so called "newbie" in the audio world.
I have a pair of Klipsch Klf-30's that are bi-amped with a Adcom GFA 55511(for the bottom) and a B&K ST2140 for the top. The Adcom I think is slowly dying, but thats ok since I havent done anything to it in 12 years. I would like to do an all tube system but dont know what to get that would still give me the volume and power that I am used to.
Could a lower powered tube amp be used for the top and a maybe say a pair of mono's for the bottom work?

Would like to do this without spending an arm an a leg if at all possible.

Anthem Pre1
Onkyo cd player
Signal interconnects
Cardas Quadlink 5c speaker cable

Any thoughts or ideas are more than welcomed and thank you in advance

Dont bother with the biamping for now.
The Adcom on my horns was harsh(mosfets). Try a Dynaco ST70 to start or if you have the money go for a SE DHT amp (Direct heated triode). Youll never go back!!!!
noting wrong with a GOOD moseft design used on horns, but that's NOT the Adcom.
& forget about that B&K.
My personal taste; I couldn't recommend tube equipment to anyone.
Mosfet's that I *could* recommend, for use with horns:
That first line made me laugh Bob. At least someone else is ok with SS on horns like. But, no, really riley there's nothing wrong with adcom-for what it is. They're not great but i think they're ok and the fact you held onto one amp for 12 years....-4 years is my longest. If you're set on keeping your klipsch you might want to also consider a nice stereo only amp for the same money like johns said, or at least do some a/b comparisons between a single stereo amp and a biamp setup of comparable price and hear for yourself. Biamping can really be good-it just comes downs to specifics at a price point and on better stereo amp v. two cheaper ones? Generally, I'm a bit less enthused with monos though since they don't do much better performance wise and double alot of parts costs (although there are exceptions). The difference between 100db channel seperation and infinite channel separation is not audible. The dyna st-70 recommended above is a good choice and you'll find a never ending slew of people offering improvements to stock,,, and i know there's more in the archives. Its kind of hard to reap the full benefits of biamping w/ passive xovers and no electronic ones. One good stereo amp (and maybe sell the B&K???) plus a little dynamat in the cabinets and on the backs of the horns could wake up the system quite a bit. my 2 cents.
Hi Ez: the Adcom may be OK for bass, but you don't want to hear it on the high end driving horns because they are so sensitive & revealing. They'll show you everything (both good & bad) about your whole lineup. That's why I don't like tubes driving horns, the microphonics & tube-rush noises are just so painfully apparent. Therefor, bargain amps sound exactly like what they are - cheap.
The Dynamat tweak suggestion is very worthwhile however.
I tend to agree with forgeting the exrta amps.Not needed and too frustrating.I drove JBL 200 studio monitors for years with a couple different single amp set ups.Tried Monos and didn't like em. With such an easy load I would enter the used market.Something like Audio Research #115 b Great peice ,well made and plenty of tube power,not expensive. Good luck!
I love it! A person asks for an opinion and he gets a wide variety of them. Here's mine: Buy a pair of low to moderately powered mono tube amps and enjoy the music. After all, these amps were designed with speakers of high
electrical sensitivity in mind.

To Thorman: I also owned a pair of JBL L200s. These were monsters and I could never overdrive using a 220 watt Parasound amp. They were the only speakers I've owned that could take the full brunt of the digital cannons on the 1812 Overture (on LP) Sorry for the aside.

Jim Robinson
Riley, what kind of music do you primarily listen to ? Sean

Tend to listen to Rock most of the time, but also have the stuff that the wife likes to listen to.


I;ve had Cornwalls and Hereseys. Granted I love my tube amps. However, the best combination I ever had was a Threshold 400 with my Cornwalls. Who can argue with 10 watts class A, 100 watts continuous and 1600 watts peak power all while you can toast marshmallows over the amp! The Threshold had more bass (tighter and bigger) than my dynaco or AR with much more power. I think that once you move up a step with amps, you will find that less power may sound better than your beasts by Adcom and B&K.
Stereophile did a piece on some Quicksilver mono's specifically designed for horns. These amps, reportedly, are dead quiet compared to other amps.
While i don't know what your budget is like, a Mesa Baron would give you what you want and do it in a full-range ( non bi-amp ) manner. Plenty of current due to multiple tubes in the output stage to control the larger drivers. The multiple tubes also allow enough juice to give you the output and bottom end that you are looking for without saturating. You can even play with how the amp is set-up to change the sound of it. To top it off, many of the rock bands that you may be listening to might even be using Mesa amps to power their guitar rigs. You can typically find these used for about $2K.

Other than that, what about the system do you think is lacking ? Sean
Imho, the horns used in the Klipsh mids and highs leave much to be desired. But, they can sound ok after some minor changes to the things, like a crossover upgrade...

Anyhow, I'd look at scrapping the xover and going bi-amped with something like a P-P 300B amp for the can do this because the horn in the Klipsh is attenuated to meet the much lower sensitivity of the woofer.

This is a good way to get involved with some DIY work, especially since you can just attach two wires and go back to the way it was and see the difference.

You'll need a crossover for the highpass to the horn, but that can even be built in to the actual amplifier, or just hung off the output end as a regular passive crossover (or a combination of both).

Regardless, the way to go for the horn(s) is triodes, imho.

For the bottom end, that's a toss up, and depends upon things like what you like to hear, the room and the way the speakers sound...

Go for it.

Horn loaded speakers of good quality are wonderful when used with the right equipment. Klipsch speakers are very sensitive and require less power to get them going. As Advantgarde (a mfg of horn loaded speakers) stated in a recent Stereophile magazine that any speakers that require at least 40 to 50 watts to get them going can't possibly reveal all the details music has to offer. Tube gear will smooth the horn loaded speakers out nicely whether the tubes are in the preamp, power amp, or both. I own 4 very large KLIPSCH speakers (CF-2's). I love them (very revealing) and I use the ARC LS1 pre with it's one tube and an Adcom 555MKII power amp with spectacular results. I prefer the power delivery of a SS amp over tube. However having tube(s) in a pre is a plus. The carpet installer commented on how wonderful my system sounded and wanted to know where he could purchase. In regards to Adcom power amps I found the 5000 series to sound too bright. But the 500 series is another matter.


Good to hear from another Epic owner. I've had my CF-4s for about 9 years now, and they are the best speakers overall that I 've ever owned. I use them successfully with an 8 watt 300b as well as a Mac 100 watt ss with a Lamm LL2 pre, and they both sound great, although different.