Power / Portable

[BeJay]

Okay Ladies and Gents got a few design questions for you.

Idea: A combo unit that is good for playing with an acoustic guitar or playing in the limited space allocated by your better half. That is portable and battery powered (or line). Raised wheels on the rear with collapsible luggage handle.

Many of the parameters I have already worked out but I would like your input. Nothing is set in stone yet.

These parameters I don't want to deviate from: (unless you can articulate a really good reason)
Sealed enclosure
Class AB - I dont want to design a class D.
I don't want to use LiIon for safety reasons - so sealed gelcell is they current option.

Here are the basic electrical questions.

Power: 8-12 / 20-25 / 30-35
Driver: 10 / 12 / 15
Freq Response:
Tone Controls: L/M/H - L/M1/M2/H
Battery Life @ 1/2 volume:

Physical: You tell me.


Keep in mind higher power - shorter battery life or larger heavier battery.

What is floating in my head is:
Power: 22w
Driver: 10"
Freq: ~50-5K
Tone: L/M/H
Battery: 4 hours

Physical:
14x20x12 cab - based on the 10" driver and loss of space due to battery.

Please have fun with the ideas but keep it real. This is a way for me to spend Jan - Mar having fun with power tools and a soldering iron.

[B-string]

Class D amp modules are available pre-built and ready for a preamp, power and speakers. Class D are much more efficient than class AB and will make your battery life much longer.
Here is a little "class T" don't know if it is bridgable. Dayton Audio DTA-2 Class T Digital Audio Amplifier Module 300-385
Just a tiny taste of what is out there these days.

[T-Bird]

Originally Posted by BeJay

Sealed enclosure
Class AB - I dont want to design a class D.
I don't want to use LiIon for safety reasons - so sealed gelcell is they current option.

No-one designs class D, they buy the module, unless it's for educational purposes.
Low power Class D isn't that difficult anyway, loads of designs and papers on the 'net. Easier IMHO than G or H. In theory anyway, I'm a tube kind of a guy . Going for A/B will sacrifice about 50% of the performance.

Gel-cell is also giving up all the advancements on energy storing, even NiMh would be better if LiIon scares You.

These would be my "parameters":


Power: 8-12
Driver: 10
Freq Response: 70Hz-5K
Tone Controls: L/M/H with switchable midpoints for flat/guitar/bass use

Physical: A wedge with a pole mount.

Regards
Sam