I'd buy a tube tester. Nothing fancy or expensive is required. Jackson 648 and Eico 667 are two good testers for the money.   Wb

Quote:   It is not the fuse that requires warmup time and cooling time. Every tube amp I've owned sounded better after the tubes have warmed up (i.e. at least 1/2 hour. This is a fair amount of time 'to remember'' exactly what an amp sounded like.   Wb

That requires down time and cooling off between fuse changes so at least several minutes would be required - then warmup time. Solution is to have two CS300XS amps hooked up to the same sources and speakers. If you can't hear the difference with your current amp just play it with the fuse in and...

Quote: The CS300XS amp is self biased and will adjust for mismatched tubes, that said the more closely both tubes in one channel are matched the better. Better yet all 4 matched tubes in the same amp.   BTW, I use some pretty high end laboratory qualty tube testers and when testing the...

Quote: No hum with my CS300XS hooked up to my Klipsch Cornwalls which are 99 dB. I've yet to try this amp on my Belles which are 103dB.   Wb

Some information I discovered with respect to hum (speaker and headphone) on the CS300XS:   Check that all six screws on the metal top plate of your amp are fastened down securely.   Wb

Thanks for the link. I though the Raytheon 5751's would sound good also RCA command and GE 5 Star. I'm considering trying out a matched quad of the Psvane EL84's (which I tried very briefly in my old Scott 222C).   Wondering if anyone has tried these tubes?   The seller purchased an...

New Member of the Leben CS300XS club here. I've kept an eye open for one of these since 1st listening to one (which was already sold) at the auhtorized dealer in Phoenix a couple of years back.   Just picked my amp up and have just set it up attached to a Grant Fidelity DAC-09 and a pair of...

That customer was me. I'm not a dedicated headphone user but do listen with headphones from time to time. I've used my Grado GS-1000 and on occasion my older Sony MDR-CD777 phones with the DAC-11 both via the SS front plug-in as well as an RCA to Headphone adapter. Both of these outputs work...