Quick question about opening a closed back combo.

[TimmyPage]

This is probably the dumbest/most obvious question in the universe, but I popped the back off my Champ 600 today to get a look at the insides (having never owned a tube amp before but knowing a chunk about wiring from my dad). I played for a little bit with the back off and noticed a subtle, but very positive difference in the tone.

So my question is this: Is it safe to leave the back off, or is it there mostly as a protective measure?

 

[Chris of Arabia]

Re: Quick question about opening a closed back combo.

It won't hurt anything in the amp or the speaker itself. I'm guessing that as they determined it sounded better with a closed back whilst they were developing it. Maybe the tubes will run slightly cooler, but that won't hurt them, if anything they should last longer. The only other reason I can think of is to stop incautious hands getting to place they shouldn't.

 

[Funkfingers]

Re: Quick question about opening a closed back combo.

The only other reason I can think of is to stop incautious hands getting to place they shouldn't.

+1

You could change the tone and retain the safety aspect by replacing the rear panel with a grille of some sort.

Alternatively, mount the rear panel on a hinge as manoeuvre it to get tonal variations - like the original Pignose micro amps.

 

[jmh151]

Re: Quick question about opening a closed back combo.

Closed back gives better bass response but a more focused directional tone. Good for stage and recording.

Open back spreads the sound around, sounds more open and 3D, and is better for smaller rooms IMO

 

[MetalManiac]

Re: Quick question about opening a closed back combo.

Open back cabinet speakers have more excursion, so potentially would have a lower power output than the rated RMS if designed as closed back. Probably not an issue with the little practice amps though.
Also, I think thatsaying bass is "better" with closed back is not true exactly .
True , there may be more bass, and tighter bass in general, depending upon the cabinet dimensions, but many prefer the spongy round bass that an open back cabinet gives...although you don't usually find open back 4x12 Marshalls, or closed back 4x10 Tweed cabinets.