Maverick boxy Rhythm channel

[Juanjo]

One year ago I bought a second hand Maverick 1x12. I founded the sound very harsh then I substituted the “original” no branded speaker by a Celestion Vintage 30. The sound of the Lead channel improved a lot but the rhythm channel is still boxy with poor low and highs. I retubed twice the preamp with original Mesa tubes and I tried JJ Tesla EL 84 in the amp section. The clean channel was still boxy and poor.

I made an A/B comparison between my amp and a Maverick head both plugged alternatively to the Celestion V30 of my combo. The sound of Lead channel was identical but as far as the Rhythm channel is concerned the test confirmed my impression. The Maverick head sounded much more full and rich with more bass and higher harmonics.

An excellent technician compared the circuits of both amps and told me that apparently they were identical. He also made all kind of measurements swapping the tubes of both amps and getting very similar results. Nevertheless he recognised that the clean channel of my amplifier sounded much poorer than the head.

This is my sad story. Any suggestions? A NOS tube in V1 position could help?

Thanks and regards

Juanjo

 

[Dave]

This may not apply directly to your complaint, but:
I have a 1-12 Maverick. I removed the Celestion 90 (I'm not that fond of Celestions) and replaced it with a JBL D-120. It brightened up the clean channel substantially. However, it still lacked low-end. I made a hinged panel to cover the gap between that aluminum bar and the bottom panel on the back of the amp, and this improved my low-end considerably. I will say this, though, it does not and will not have the fullness of a 6L6-powered amp.