Babelfish XA252 / Babelfish XA252 SIT / Babelfish XA252 SET

[Vunce]

"More silliness caused by crimp connectors on A/C input/fuse dohicky."

Are you sure its the crimp connectors being silly or not properly crimped. Or using a .250" connector on a .187" tab?

 

[william2001]

I know. Do you really want to hear this? More silliness caused by crimp connectors...

russellc

Good ol' crimp connectors... I can replace the word "crimp" with "RCA" also in that sentence in my case a couple of weeks ago (again).

I had to see the doctor too after that..... 😷😠

 

[Zen Mod]

well, I'm praying for that amp

 

[Russellc]

Back from doc, going to heat it up and let it sit and cook a while.

 

[Russellc]

Cruising, one channel can only dial up to 178, other side 176. I guess both channels are pot limited. This is plenty ho enough to cook in!

 

[Russellc]

Nice and toasty. 178 mV on each side, after jumper install, set offset and remove has both channel under 1 millivolt right this min. I will let it go for about 30 more mins and if no explosion, test speaker time.

 

[Russellc]

Backed it down to 177, offset under 1 mV both sides for 15 mins now.

 

[Zen Mod]

just hook it to spks and listen

 

[Russellc]

It has been 30 mins, but I keep having bias slowly rise to 178, dial back to 177. Would like to see this stabilize before music plays.

 

[von Ah]

Your definition of stabilize is too strict. It seems you have everything you need to test with speakers.

 

[Zen Mod]

It has been 30 mins, but I keep having bias slowly rise to 178, dial back to 177. Would like to see this stabilize before music plays.

Iq is under 5% deviation from cold to temp. equilibrium
same as for +/-10% rails change, due to possible mains voltage change

in fact, quite possibly under 5%,lazy to check my notes, and who cares ..... once when it is good enough, it is good enough

so.......

 

[Russellc]

Ok stable -speaker time

 

[Russellc]

Oh, I guess I need to snip off the wire going from positive input to ground now, before music

 

[Zen Mod]

well, if you want music, yes

please, do that with amp powered off

 

[Russellc]

And it plays fine, no hum, just Bill Evans right this minute.

 

[Russellc]

Sounds Very nice, steady 1-2 0r less mV offset, bias steady at 176 mV. Heatsink behind devices is 50-52C. Device, by shooting edge reads lower, not much buI seriously doubt its accuracy. I would think device would be hotter, but whatever, amp is playing in grand fashion. I'm about to put a pin in this one after a few on off cycles.

 

[Zen Mod]

No Porn, No Glory

 

[Russellc]

Put back on work table to solder A/C input wires, will put in main system tomorrow and photo it.
I built this amp to driver the speakers in that set. X's XSD speaker.

Russellc

 

[flocchini]

Russel
Fantastic numbers - tell us about the sound! - is your foot tapping? - both feet?

 

[Russellc]

Yes, very nice. Tried it on test speaks, then on tektons. That was nicer! Got too late to put in main system, which is what built for, did get it back on table for soldering crimp connectors.