Class D Hybrid Quickie

[Fleawatt]

At the risk of being tarred and feathered by my fellow tube lovers, I'm going to post this anyway.  I've been playing around with some class D amplifiers lately. (I know, I know- I'm saving for a Stereomour)  I decided to stick a small, battery operated 8 watt amplifier board inside my Quickie chassis.  I used the two input holes for binding posts and made the output, the input.  I put a DC battery input plug between the 9 volt and D batteries.  I use an external 12 volt battery to power the TPA3110 board.  Front power switch controls amp power and back switch still controls preamp power. I did have to use a voltage divider on the inputs of the Class D as it is pretty sensitive by itself.

 

[Paul Joppa]

Sweet!

I love the way a $100 preamp encourages experimentation.

 

[earwaxxer]

thats pretty cool! - I had my Quickie hooked up to my t-amp at first. They sounded GREAT together! Thats what started the whole thing with me. The Quickie can open some doors and some minds to what is possible.

 

[4krow]

Dammit Eric, that's what I was gonna say!

  Well anyway, I have a T-amp that I'm using in my garage system, and now you guys are forcing me to experiment with it. It could be a good combo since my speakers are 94 db.

 

[Paul Joppa]

Are any of you thinking what I'm thinking? The best possible price/performance? Quickie - T-amp - fullrange - or??? Not a contest, more a celebration?

OK, it's Friday night and I've had a cocktail and plenty of old red wine. Still ...

 

[Zimmer64]

Are any of you thinking what I'm thinking? The best possible price/performance? Quickie - T-amp - fullrange - or??? Not a contest, more a celebration?

OK, it's Friday night and I've had a cocktail and plenty of old red wine. Still ...

That's pretty close to what I use it with. Since I started the audio DIY hobby only a few months ago I have not tried a T-amp, but I am using the Quickie together with:

Gainclone @$98 http://zimmer64.wordpress.com/2012/12/16/gainclone-lm3875-updates/#more-208
Fullranger (Fostex FX120) http://zimmer64.wordpress.com/2012/10/10/double-bass-reflex-loudspeaker/#more-19

Really love the sound of the combination and listen to it more than I do listen to my main system.

@Fleawatt: Very cool idea implementing an integrated amp!

Michael

 

[Fleawatt]

Thanks for your nice comments! 
The sonics of the newest Class D Texas Instruments IC's are quite good.  I prefer them over the gainclones and Tripath amps I've owned over the years.
In my personal Class D journey, I found a kit which I prefer over the Made in China Sure boards.  It allows for capacitor and resistor experimentation.  It's $23 and $2 for shipping and Made in USA.  Can't beat that for taking your Quickie into amplifierdom. 
http://www.jerryselectronics.com/diykits/kaa03021/kaa03021.htm

 

[Fleawatt]

Are any of you thinking what I'm thinking? The best possible price/performance? Quickie - T-amp - fullrange - or??? Not a contest, more a celebration?

OK, it's Friday night and I've had a cocktail and plenty of old red wine. Still ...

And at the risk of sending this thread in the wrong direction, after building over 15 different full range driver speakers over the years, I've yet to find anything that can compete in the price/performance category of a full range speaker than the Wild Burro Audio Labs "Betsy" full range driver in a large open baffle.  Think Fostex 206e league with gobs of bass, stuck on a slab of large plywood, no peaky shout and $100 for a pair! 

 

[Zimmer64]

That's interesting. Read about the Betsy in OB. I will try them. Which baffle size / shape did you build? Did you try the JE lab style?

 

[earwaxxer]

Thanks for your nice comments! 
The sonics of the newest Class D Texas Instruments IC's are quite good.  I prefer them over the gainclones and Tripath amps I've owned over the years.
In my personal Class D journey, I found a kit which I prefer over the Made in China Sure boards.  It allows for capacitor and resistor experimentation.  It's $23 and $2 for shipping and Made in USA.  Can't beat that for taking your Quickie into amplifierdom. 
http://www.jerryselectronics.com/diykits/kaa03021/kaa03021.htm

I agree - today there are many more choices in class D, and the old t-amp has met its match. Hypex comes to mind, and Class D audio out of china has some good kit. Im happy with my 85lb Emotiva so I'm staying pat, but you could very easily build a all battery powered integrated Quickie based on class D for not much bucks.

 

[Fleawatt]

That's interesting. Read about the Betsy in OB. I will try them. Which baffle size / shape did you build? Did you try the JE lab style?

Here's a link so this thread doesn't spin out of control.  ;D
http://www.diyaudio.com/forums/wild-burro-audio/
I built the donkey kongs, but I would probably go with a piano hinged tri-fold style baffle.
I made a trifold for my Saba greencones and like the flexibility and smaller size.

 

[4krow]

In the past, I have used Audio Nirvana drivers. I think that these drivers that are now sored in my basement may become part of the push to this very cool idea. I remember the T-amp that I had sounding much better than it should have, so now that there are better products available, it is worth some consideration. Maybe for a dorm room application.

 

[Fleawatt]

I shot a short iPhone video of the Class D Quickie horsing around with my Saba Greencone open baffles.

http://www.youtube.com/watch?v=nZe9texn0M8

 

[jrebman]

Flea',

Many thanks for posting this -- this looks really cool and I have some friends who just might really be interested in having me make an amp like this for them.

I also like that the amp pcb is through-hole.

Thanks again,

Jim

 

[earwaxxer]

Hey Jim - I agree - A hybrid Quickie would be awesome. I'm using it as such in many different configurations. Its awesome. Tubes in the circuit are definitely a plus. The more the better.

peace, love etc. - Eric