[Pendergast]

Hello,

I understand that CMOYs are nice little amps. I have done a few and appreciated the activity of making them.

Now, I am interested in moving up a bit. I understand that the MINT is an improvement over the CMOY. But I want to know how this design can be further improved for the newbie DIYer like me. I am confident I can make one, but for the sake of having a challenge, I am interested in making one with the improvements that people have made over the design provided by Tangent.

Are there any suggestions? Or "recipes" already available that anyone know of that could orient me?

I have a cigarette case in brushed metal waiting for this little thing that I want to work on. I am confident it could fit 2 9V batteries and a MINT. I am even thinking that it could fit some kind of recharger for these 9V batteries.

Thank you.

(I cannot find an Internet reference to the case but if you want a picture, you could look at kloan's first posts in the DIY forum).

 

[Pars]

The MINT isn't really configurable, other than parts selection, as it is intended to pack a buffered opamp into the smallest footprint. If you want something that is more tweakable, I would suggest the Pimeta. If you really need something that small, then I would wait for Tangent's AD8397-based MINT 2.0 (see headwize).

 

[Twombly]

I believe it's called the "PINT" now.

 

[guzzler]

You could implement a bass boost, which is for my money a good addition for a portable amp. You’d need a couple of pieces of stripboard to sit atop the usual positon. If you were really keen, you could make it adjustable... I’ll post specifics if you need them....

Another possibility is to try experimenting with different buffers. If you use an opamp buffer (an OPA551 would be good in terms of current drive. I have not heard one, and cannot vouch for it's sound), it's very simple. Think unity gain... If you were feeling very ambitious, you could try shoehorning an HA3-500x in there; you'd need to construct somehow a little SMD to SMD adaptor.

Try using a real ground, as opposed to virtual. Probably too big to use in that case if I'm thinking the same thing, but realisable with an external supply....

Make it a 3 channel amp a la PIMETA schematic.....


Hope those ideas help, make sure to post some information/pics if you succeed (sure you will)

 

[Pendergast]

Quote:

Originally Posted by guzzler You could implement a bass boost, which is for my money a good addition for a portable amp. You’d need a couple of pieces of stripboard to sit atop the usual positon. If you were really keen, you could make it adjustable... I’ll post specifics if you need them.... Another possibility is to try experimenting with different buffers. If you use an opamp buffer (an OPA551 would be good in terms of current drive. I have not heard one, and cannot vouch for it's sound), it's very simple. Think unity gain... If you were feeling very ambitious, you could try shoehorning an HA3-500x in there; you'd need to construct somehow a little SMD to SMD adaptor. Try using a real ground, as opposed to virtual. Probably too big to use in that case if I'm thinking the same thing, but realisable with an external supply.... Make it a 3 channel amp a la PIMETA schematic..... Hope those ideas help, make sure to post some information/pics if you succeed (sure you will)

I am certainly not that ingenious...

;o)

BUt thanks for the advice. I am expecting the MINT board soon, and some stuff.. so I'll start with the basic.

 

[Pars]

The biggest improvement you can make would be to put in bandwidth resistors... something around 220-475 ohms. This will improve the bass response particularly without really doing a number on the current draw. Dougigs (head-fi member) did a nice writeup on his findings on what gave him the most improvement on the MINT he built, and this included stacking buffers, which he determined wasn't worth it (do a search, maybe on Dougigs as author and MINT or BUF634). I'm currently helping my son configure his Pimeta, and I tried the stacked buffers, but then unstacked them and put in the BW resistors and I agree with what was said in terms of the most bang for the buck improvements WRT portability (battery power) and current draw. Just my (devalued) $0.02.