Apheared
You call that an amp? THIS is an amp!
- Joined
- Jun 20, 2001
- Posts
- 377
- Likes
- 10
I'm gonna type this in the hopes no one reads it.
ppl's portable amp design is the one amp I like Grados on more than a well-built primo Szekeres. And it's portable. (kinda) It's a biased opamp buffered with a machine gun... in the original it was 825 into 2008s, but I had a CRD fail and took the 825 to the grave. I did an 823, and you know all about that.
But I can't take it anymore. 180-250mA isn't much at home, but on the town it just eats batteries like nobody's business. I was up for it before, but now I just can't be bothered with it. Still, it's a great amp and I want to use it.
Also, I've never NEVER built an AC only amp, other than a few Szekeres. They might run off that stuff in the wall, but you could always unplug them. Even discretes... everything battery.
Red letter day. Retrofit this battery-eating beast with a power supply, utilizing the same case.
-----------------------
aos laughed at me when I said I had to use heatsinks on my battery amp... well, just to let ya know before I gutted it I took this shot... remember that this is with the CASE OPEN (on for 30 mins).. I don't wanna know how hot they'll get w/o sinks.
So anyway...
Sheesh, you're still reading this? you are as bored as I am...
Here's what it looks like now. I'm not gonna go off about how silent it is, how perfectly flat the noise is and immeasurable for me, how ****ing black silent it is at any volume you can't tell it's on.. no, I'm not gonna talk about that.
Anyway:
Talema 15V/1A xform
IR 400/6 bridge (hey it's what I have)
2x Teccor 4700uF/50V
317/337 with resistors and 10uF adj bypasses
(philips 10uF/40V if you actually care)
2x Wima 1uF/63V
4x Elna 470uF/35V
Noble 10k pot
everything else is re-utilized.
Two things for the only ones that read down this far:
Dan, you're right re: turn-on glitches/pops/whatevers. It's something to do with Cerafines. I had others in here and they change from a full pop, to just a switching glitch, to silence... and the silence is Cerafine. WELLWHADDAYAKNOWABOUTTHAT? Great discovery, I'm sure there's other things that can do this but hey...
ppl, get this... the bass is better on AC with smaller capacitance... so batteries must have much more series resistance when we stack em that hard than I ever thought. I had 48KuF per rail, and the bass is so much better on the dual 470 Cerafines. "Better" in that it's crisper/snappier, heavier impact, more detailed, just all in all BETTER. You gotta try dropping that capacitance down. I tried from none to 5600, this dual 470 is just damn gorgeous.
edit: 15V @ 1 or 30VCT @ .500, but not 15VCT @ 1. My bad.
ppl's portable amp design is the one amp I like Grados on more than a well-built primo Szekeres. And it's portable. (kinda) It's a biased opamp buffered with a machine gun... in the original it was 825 into 2008s, but I had a CRD fail and took the 825 to the grave. I did an 823, and you know all about that.
But I can't take it anymore. 180-250mA isn't much at home, but on the town it just eats batteries like nobody's business. I was up for it before, but now I just can't be bothered with it. Still, it's a great amp and I want to use it.
Also, I've never NEVER built an AC only amp, other than a few Szekeres. They might run off that stuff in the wall, but you could always unplug them. Even discretes... everything battery.
Red letter day. Retrofit this battery-eating beast with a power supply, utilizing the same case.
-----------------------
aos laughed at me when I said I had to use heatsinks on my battery amp... well, just to let ya know before I gutted it I took this shot... remember that this is with the CASE OPEN (on for 30 mins).. I don't wanna know how hot they'll get w/o sinks.
So anyway...
Sheesh, you're still reading this? you are as bored as I am...
Here's what it looks like now. I'm not gonna go off about how silent it is, how perfectly flat the noise is and immeasurable for me, how ****ing black silent it is at any volume you can't tell it's on.. no, I'm not gonna talk about that.
Anyway:
Talema 15V/1A xform
IR 400/6 bridge (hey it's what I have)
2x Teccor 4700uF/50V
317/337 with resistors and 10uF adj bypasses
(philips 10uF/40V if you actually care)
2x Wima 1uF/63V
4x Elna 470uF/35V
Noble 10k pot
everything else is re-utilized.
Two things for the only ones that read down this far:
Dan, you're right re: turn-on glitches/pops/whatevers. It's something to do with Cerafines. I had others in here and they change from a full pop, to just a switching glitch, to silence... and the silence is Cerafine. WELLWHADDAYAKNOWABOUTTHAT? Great discovery, I'm sure there's other things that can do this but hey...
ppl, get this... the bass is better on AC with smaller capacitance... so batteries must have much more series resistance when we stack em that hard than I ever thought. I had 48KuF per rail, and the bass is so much better on the dual 470 Cerafines. "Better" in that it's crisper/snappier, heavier impact, more detailed, just all in all BETTER. You gotta try dropping that capacitance down. I tried from none to 5600, this dual 470 is just damn gorgeous.
edit: 15V @ 1 or 30VCT @ .500, but not 15VCT @ 1. My bad.