Comments on DIY Audio Projects - Hi-Fi Blog for Audiophiles: Audio Paradox - S-5 Electronics K-8LS Tube Amp Kit...

Hi Gio,My speakers are JBL XTi 100. Maybe it's bec...

2007-12-16T09:00:00.000-06:00

Hi Gio,
My speakers are JBL XTi 100. Maybe it's because they are 6ohm that the sound level was low ? or maybe the 92dB/W are without the filter ? Or maybe the filter does just attenuate low frequencies to the medium and tweeter and the two bass speakers are taking all the power ? (but I don't think it's that...)

Hi Benjamin,Bruce measured the amp to be -9dB at 2...

2007-12-15T15:10:00.000-06:00

Hi Benjamin,

Bruce measured the amp to be -9dB at 20Hz relative to 1kHz. That explains the poor bass response.

With 92dB speakers, you only need 2 watts of power to produce 95dB which is plenty loud. What kind of speakers are they?

With tube amplifiers, a high output impedance (and low damping factor) is common.

Bruce, thank you for the notes and measurements ab...

2007-12-14T17:34:00.000-06:00

Bruce, thank you for the notes and measurements about the K-8 tube amp kit. I am a novice and was looking at the K-8 as my first kit. I have read many good things about the K-12 tube amplifier kit, so I will try that one instead.

Hi,I bought a K-8LS amp because I live in Europe a...

2007-12-14T08:49:00.000-06:00

Hi,
I bought a K-8LS amp because I live in Europe and it can run on 230V. I was a bit disapointed (I read lot of good things about K-502) when I listened to it : in my opinion, there was no bass and the power was very low (maybe that's normal, I got 92dB/W/m speakers, 6ohms).

Another thing, the internal resistance is about 16ohm (I don't really know much about tube amps, but I think that's high..!), that makes a damping factor of 0.5 on 8ohms speakers.