Kaiju Break in process only in midband of acitve system?

[fritzthecat]

I finished my first Kaiju using stock parts over the weekend and I am absolutely surprised how much impact the filament upgrade has regarding the reduction of hum in my system (very high efficiency speakers above 102 dB, active crossover with DSP (MiniDSP), the Kaiju I am talking about is used for mids from 240Hz to 12 KHz - I am still playing around with the settings).

Before the installation of the upgrade the hum was unbearable and I actually even was kind of dissapointed and never did expect the impact of the upgrade being that big. I mean, the hum is still there but at a super low level - amazing!

I'll go ahead breaking the amp in (it was running for about 30 hours over the weekend - no problems at all) - it only has about 50 hours operation time so far - and start building the second one using boutique parts and solid silver wiring - looking forward to compare them later on...

Talking about breaking the Kaiju in: As I am using it in a active system and not fullrange at the moment a question popped up in my mind: Does anyone have experience about breaking the amp in in such a system? Is it okay to only use it in the midrange band during this process or would it be better to just connect it to a fullrange speaker so it can break in over the whole hearable bandwidth? Any recommendations - I have both options available but of course would love to listen to the amp in my big system.

By the way: I have this blue glow effect inside the 300b tubes as well but it is much more on the right side where I have more microphony effects as well.

 

[Doc B.]

I am surprised that you are absolutely surprised. We try to be very specific in describing what our upgrade kits will do for the performance of our kits, and the DC filament supply is very specifically recommended for builders who use hypersensitive speakers. Have you nulled out the residual hum as well as possible with the hum balance pots? If you have not, you may be able to get the level even a bit lower. Break-in will happen just fine using midband frequencies.

[fritzthecat]

Thank you! Just wasn't sure about break in process being dependent from frequencies or not and yes, I nulled the hum using the pots and they are still in the same position.

To make it a bit clearer: I am absolutely surprised because there now is less hum than I had with the ultraquiet Passlab transistor amps I was using before and because it looked like the hum was coming from a ground loop or interferences or my unability to get things done right - so actually the hum should still be there even with the upgrade.

I didn't want to say that you don't understand what you are doing - English is just not my mothertongue - aber i mue da Änglisch schriibe wil i glob nöd das da irgendeine Schwiizerdütsch wür verstoh, drum versuech i da halt mi innere Frömdsproch us'z'druckä und mängisch tüpf i's halt nöd so ganz.

In case someone does not understand Swiss German: - but I have to write in English here because I do not believe that anyone would understand Swiss German, that's why I just try to articulate in a foreign language and sometimes I don't get the words quite right.