Jeff Rowland 501s burn in ... a strange experience


I have received today my monoblocs 501 and borowed a ML 39:
ML 39
NBS monitor III
Capri
NBS Monitor III
monoblocs 501
NBS Monitor IV
Infinity Renaissance 90

around 2:p.m (Europe) I have installed the system:
sound very detailed, beautifull soundstage imaging & focus, great energy,
on the negative side, some high frequencies too harsch a little bit venomous

6 hours later (system working all the time) complete change ... do the monoblocs suffer jet lag? ... ;-)

the sound has become very fat and heavy, has the energy of a sleepy hypopotamus, everything is slow, too warm, without focus, like coming from bad tube components ...

from one extreme to another... how is that possible, so extreme, I am ???

any suggestions?

thanks
clavil
After a few hundred hours if your not satisfied I strongly suggest upgrading your power source with a dedicated circuit and metal clad heavy gauge wire. Some switching amplifiers can be fussy about the AC their being fed. This is an inexpensive upgrade that your entire system can benefit from.
Nothing having to do with the JR 501's underwent any permanent or long lasting change from about 10 seconds after you powered it up to 6 hours later, or for that matter, till now. If it did, then the equipment is poorly designed. Since that company has been around for a while and has many satisfied customers I doubt that it is that poorly designed.
Clavil, the glib answer would be. . . take 2 Aspirins and call me in 6 months.

Here is a more useful answer. . . all new amps need real playing time break-in. . . during this time sound will fluctuate wildly. Different types of amps require different break in times. Seems that amps that operate at lower temperatures require longer break in time. Most class D Rowland amps require about 1,000 hours of REAL playing time to reach peak performance. You should also leave your Capri pre and 501 amps always turned on. . . this is JRDG's recommendation.

Once the amps are broken in, you may want to consider a pair of JRDG PC1 PFC external modules. . . they should yield greater authority and greater subtlety to the sound. Power cords should probably be after that. G.
Clavil, I have developed a fun to use Excel spreadsheet that helps with equipment break in tracking/logging. Drop me a note if you'd like to try it out. G on the 501 break in.