Primaluna & Klipsch Cornwall frustration HELP


Well this is a little frustrating. I have a Primaluna preamp and Primaluna Dialogue 5 power amp. Found a great deal on some Klipsch Cornwalls. Heard Klipsch and tubes were made for each other. Hooked them up and it had very little bass. I was expecting a BIG sound. Sounded almost anemic. Hooked them up to a class D audio amp through the Primaluna preamp and it was fantastic. Lots of slam. A great rock and roll sound. These are very efficient speakers so I don't get why they don't sound good through the tubes. 42 watts per channel at 8 ohms. Happened to talk to a Primaluna guy and he told me I needed a more powerful Primaluna amp. That has got to be BS. Do I have bad or weak tubes?? These are KT88's! Maybe they are going out. Who knows. Tried to call Kevin Deal at Upscale but he is out of town. I am not buying a bigger Primaluna amp. Kind of offended that I was even told that. Would the KT120's make a difference? Could it be something else wrong with the amp. Thanks for any help. By the way the amp sounds sweet with small monitors where I don't expect much bass. Thanks for any direction.
128x128dylanfan
It sounds good just missing the low end. Not as clean as my LS50's or Dynaudio speakers but will probably be a great rock and roll speaker when I get the bass added in.
To give you something to look forward to, with my speakers, the difference between using the 4 ohm and 8 ohm taps is substantial. In 4 ohm the bass is nice and tight - very present. In 8 ohm it is less transparent in the bass - but not necessarily boomy, just makes the sound a bit foggy. My speakers are nominally 8 ohm speakers.

And, in my Dialogue 2, I use Tong-sol 6550's which I find add some tonal richness in the upper bass/lower mid range when compared to other 6550's and KT88 (that I have on hand, anyway).

Out of curiosity are you using a Dialogue 3 pre-amp, or are you using its predecessor, the PL3. I ask because until I matched my old PL5 with the PL3 its bass was weak/thin (when using ARC and a Magus pre-amps.
OK- in review, here are the things you need to try:

1) try a different tap (4 ohm)

Notes: the speaker is nominally 8 ohms and likely has a nice impedance bump in the low end that might help your amp out. Any notion that this amp cannot control the woofer is nonsense- this speaker was designed for amps with high output impedance.

I am thinking that the impedance is not the issue here.

2) try reversing the phase of one speaker *only* (not both!).

Notes: If it appears that you have your speakers wired correctly in phase, it may be that your amp has its output out of phase in one channel. In a zero feedback amp, this could happen due to a wiring error as there is no feedback to cause the amp to oscillate (which it certainly would do if it had feedback).

IOW, I suspect phase is the problem.

FWIW, we have customers using that speaker with our M-60 amplifier, which also has a fairly high output impedance and they report impressive results. So you should be able to make this work unless something is outright wrong with the amp.
I am using it with a Primaluna Premium preamplifier. Thanks for the advice stmadphere. I will reverse the phase of one speaker when I get home over Labor Day. This amp hardly gets played because I travel so much. I would like to just go home, turn it on for the little bit of time me I am home and enjoy it instead of trying to figure out why it doesn't sound right.
08-22-15: Dylanfan
By the way the amp sounds sweet with small monitors where I don't expect much bass.

08-24-15: Dylanfan
It sounds good just missing the low end. Not as clean as my LS50's or Dynaudio speakers but will probably be a great rock and roll speaker when I get the bass added in.
FYI, in addition to causing a lack of bass a polarity inversion in one speaker (i.e., + and - being interchanged, either due to a connection error or due to a wiring error in the amp), would result in imaging that is vague, diffuse, and hard to localize, and would probably also cause the midrange to sound a bit strange.

I suspect that going to the 4 ohm tap will strengthen the bass at least a little. But to what degree, and with what other effects, are hard to predict. It's definitely worth trying, though, as several of us have suggested.

Regards,
-- Al