[NotoriousBIG_PJ]

So can these portable diy amps be made with awesome power supplies if one just wanted transportability, not portability? Also does a medical grade wallwart make things sound better then normal wall warts?

Biggie.

 

[jarthel]

It's been discussed in headwize that medical power supplies are better than ordinary dc adaptor.

 

[NotoriousBIG_PJ]

ok is this right:

You build a power supply for the amp and then you plug a wall wart into it?

Biggie.

 

[puppyslugg]

NotoriousBIG_PJ:

"You build a power supply for the amp and then you plug a wall wart into it? "

If you go that way, use a ac wallwart and have the rectifiers, regs. etc. inside the chassis. Or you could use a dc wallwart and just have just the regulators inside chassis. Of the the two possibilities, I would go with the ac wallwart because that way you have control of which retifiers to use, preferably shottky's. I would use the biggest (amperage) wallwart I can find or afford. Within reason, of course.

But if you want the 'ultimate psu',the Gilmore psu would a good choice, as are the Jung and Bobely/Sultzer psu's.

Jarthel:
"...that medical power supplies are better than ordinary dc adaptor."

As long as it isn't a switching supply. Though some non- switching medical supplies may not be 'audio' grade. (poor regulation, etc.)

 

[NotoriousBIG_PJ]

Quote:

Originally posted by puppyslugg But if you want the 'ultimate psu',the Gilmore psu would a good choice, as are the Jung and Bobely/Sultzer psu's.

How do those plug into the wall?

Biggie.

 

[puppyslugg]

Hey Biggie,

The wallwart plugs into the ac outlet and the output of the wallwart plugs into (psu inside) the amp.

 

[geom_tol]

My meta42 uses 8 AA's per channel connected directly to the power rails, with 3 1000uf cerafines / channel reservoir caps.

I doubt this ps can be improved on much.
I have another meta42 board I haven't used yet. I guess I can build one channel on it and make a dual mono amp using two boards. That way the ps would separated also. That would be a theoretical improvement at least.

The bass on my meta42 sounds as good as the Max's bass IMO.
I'm using el2008's as buffers.

 

[NotoriousBIG_PJ]

nothing. i didnt say nothing

 

[ppl]

I have found that regardless of topology all things being equal the Lower ripple low impedance well bypassed power supply be it batteries like "geom_tol" 8 AA's per channel Hear you have IMHO a real quality supply equail to or better than all but the most complex Gilmore and Jung Supplys. NI-MH batteries have a low impedance over a surprising Frequency range add multipull levels of Electrolytic +Film + Foil or Silver Mica with slower less than 50 MHz circuits Polystyrene. just as eather of the Afore mentioned supplys.
aos i will use separate batteries in your dAC to resolve the DC on the POT Issue and if using two sets of batteries is required for True DC coupling fron the DAC's out. Good it is that importent to me.

 

[kelly]

Quote:

Originally posted by geom_tol My meta42 uses 8 AA's per channel connected directly to the power rails, with 3 1000uf cerafines / channel reservoir caps. I doubt this ps can be improved on much. I have another meta42 board I haven't used yet. I guess I can build one channel on it and make a dual mono amp using two boards. That way the ps would separated also. That would be a theoretical improvement at least. The bass on my meta42 sounds as good as the Max's bass IMO. I'm using el2008's as buffers.

geom
Your Max is the old version, right? Not the 2001+ model? If it is the 2001 (which I've actually heard), how would you compare the other aspects? What does the Max do better? What does the META do better?

 

[KurtW]

geom_tol, have you made comparisons with the EL2008 and other buffers? If so, your comments would be interesting. Also, where can you Elantec buffers?

 

[aos]

EL2008 are the ultimate buffers according to ppl and no longer manufactured. They can supply 1A of current. If a properly built amp using that beats the Max, nobody should be surprised.

It is very tough to get couple thousand uF bypass per channel in a portable device. There is usually no space for that. Even then it can hardly be called ultimate power supply. It's just a battery bypassed with some caps. Super regulated supply will sound better. There is a reason why professionally built amps sound better than most DIY, and this is probably one of them.

 

[geom_tol]

Yep, my Max is the older model.
Both the amps sound really good. They both do everything really well so it's hard to say what is better or worse on them. When listening to these amps you don't hear the amps, just the music. This is what I listen for when listening to equipment.

Aos. I need to make a good ps. It's been on my list for a long time but never gets done. I'm now waiting for your versatile ps board you wrote about a while back.

I haven't done extensive comparisons between the el2008 and el2001. From what I've done I feel like the bass is better on the el2008. But it's not huge on the headphones I've been using (hd580, dt931). I need to find some headphones that are more sensitive to differences in amps. Maybe sony v6. Right now I have very little time for electronics projects, I'm going to be on the road for almost a whole month.

I'm selling some el2008's for exactly what I paid for them a while back. check the classifed board.

 

[puppyslugg]

"I haven't done extensive comparisons between the el2008 and el2001. From what I've done I feel like the bass is better on the el2008."

Did you stack the el2001's?

 

[MacDEF]

Just to add my 2 cents to this thread, before hearing KurtW's META, I would have agreed with the (general) assertion that bass on most of the DIY amps isn't up to par with some of the good commercial amps. However, after hearing Kurt's META, I'm a convert -- in fact, when I tried it out, the first thing that grabbed my attention was the tight, deep bass on a pair of HD 600.