Fun with a Chip Amp

[Lazarus Short]

During the long process of getting my wife's computer upgraded (now done!), we switched to a set of Altec computer speakers we had lying around, and I trashed the other pair, as they did not sound nearly so good. As I often do, I opened them up to see what the innards looked like. The speaker drivers looked nicer than I expected, with bigish magnets and separate cones and surrounds - they might make good midrange speakers. Inside one enclosure was the chip amp, with volume and tone controls, lots of resistors (gold banded, and that means close tolerance), capacitors, and the Toshiba chip. Well, today I wired them up with a cable to plug them into the portable CD player, two cables for speakers (hooked up the Mission 70's), and two wires with alligator clips to connect to power (a 6 volt lantern battery).



It seems the speaker drivers were the limiting factor - I put a CD by Radio Tarifa on, powered up the amp, and cranked the volume controls of both the amp and the CD player. Wow, oh, wow! It sounds more than good! It has snap, and the pace, rhythm, and timing thing is all there. The only failing is deep bass - it just can not deliver enough current for the woofers. I confirmed that with a CD by Sorten Muld. There is enough power overall for sealed speakers, so I'm trying them on the Klipsch Heresys next. Report later...



All this from an amp about the size of a pack of cigarettes! I'm more than impressed.

 

[dingus]

i've enjoyed the old Sonic T-Amp, SuperT and Trends Audio T-Amp in various systems over the years. with the right combination they can be surprisingly good.

 

[Lazarus Short]

Yes, I'm surprised at what this thing of mine can do in the midrange and treble, and it's not really even hi-fi. In a few days I'll see what it do for my Heresys. I think there could be a better chip amp in my future...

 

[laatsch55]

Lazarus, one of the ongoing projects here is the upgrading and power supply replacement on 53 of the last remaing X-Amps. Built around the ??? Chip. 125 watt mono blocks. Joe redesigned the switching power supply they had with a mosfet regulated toroid. Larrt, Jer and I are in this deal and sometime this spring I'll get the toroids and power supply PCB's and we'll have some X-Amps to liquidate. Check for the x-amp threads, surp[risingly good asounding ;little amps.

 

[Lazarus Short]

You bet I will. Monoblocs would be way cool.

 

[Web Police]

I don't know about chip amps, but when I was younger I took apart old clock radios, portables and several other small radios and palyed them back through much better speakers and they didn't sound too bad.

The last suck experiment was with a Nak all in one cd/receiver combination. I got it used and it didn't spound real good wit hthe speakers it came with, but when I hooked the little 7wpc amp up to some large three ways it really sounded good. Could be the speakers i got with it were not up to snuff, but visually they looked fine and the drivers seemed to work fine, but they just couldn't move enough air to do justice to the sound without a sub or larger woofer of some sort.

 

[Lazarus Short]

Web Police, those speakers were probably just too inefficient for that seven-watt amp. I used to have a ten-watt single-ended tube amp on some three-ways, and it sounded glorious. I'd love to try the Nak amp on my Heresys. BTW, here's a photo of my latest stereo system, minus speakers (My wife says it reminds her of the crystal radios her dad used to fiddle with.):

 

[Web Police]

Web Police, those speakers were probably just too inefficient for that seven-watt amp. I used to have a ten-watt single-ended tube amp on some three-ways, and it sounded glorious. I'd love to try the Nak amp on my Heresys. BTW, here's a photo of my latest stereo system, minus speakers (My wife says it reminds her of the crystal radios her dad used to fiddle with.):

Nice looking system there. At least you could hide it in just about anything.

I sold the Nak on ebay back before the economy crashed and got $100 plus for it. I think i paid $20 for it at a pawn shop a year earlier. I think I just tossed the speakers because if I sold them with the amp someone would have complained that the amp didn't work correctly. The speakers were not Nak branded anyway so they were probably inefficient and shouldn't have been paired with the amp anyway. I supposed a little 7 watt amp probably would have driven my fairly efficient Kilpsch horn loaded speakers fairly well though?

 

[speakerman1]

I forgot all about the X amps.

 

[laatsch55]

Me too, till I stumbled over a box of em in the shed the other day.

 

[dingus]

the X-amps sound promising. i might be interested in a couple of the modded jobs.

 

[Fairchild]

Me too.

Jim

 

[laatsch55]

Damn, with this much interest I better get this ball rolling again. Larr and Jer gonna be busy converting X-Amps. Got 53 of the darn things.

 

[Web Police]

I am interested in a pair once they are finished.

I figured the x-amps are like the x-files, the gov came in and confiscated all of them and refuses to acknowledge they ever existed.

 

[Lazarus Short]

No, they are just "filed" in Lee's shed.

BTW, I just found out on the Vinyl Engine that this chip amp is 2.5 watts @ 10% distortion, so it won't be tried on the Heresys after all. It's boxed up, and soon to be forgotten...

 

[laatsch55]

Youse guys are funbny today!!

 

[orange]

I don't know about chip amps, but when I was younger I took apart old clock radios, portables and several other small radios and palyed them back through much better speakers and they didn't sound too bad.

The last suck experiment was with a Nak all in one cd/receiver combination. I got it used and it didn't spound real good wit hthe speakers it came with, but when I hooked the little 7wpc amp up to some large three ways it really sounded good. Could be the speakers i got with it were not up to snuff, but visually they looked fine and the drivers seemed to work fine, but they just couldn't move enough air to do justice to the sound without a sub or larger woofer of some sort.

I had a 7-watt Kmart brand two shaft AM/FM cassette car stereo in my Duster and somebody cut 6x9" ovals in the side panels in the back so I put my brother's old Sparkomatics in.

Those narrow channels opened into the trunk and there were holes in the rear shelf (including a 8" circlular one in the center and I covered it some.

BOOM. I butchered the door panels to add door speakers but it didn't work well, cracking the wires...no conduit!

Still, seven watts, if you were LUCKY, did the trick!

 

[orange]

If I'm lucky I'll get that spare Yamaha CA-1000 Mk III integrated from DaveInVA in good time. X-amps are cool, a great Yamaha is a sonic wet dream.

 

[Lazarus Short]

I had a 7-watt Kmart brand two shaft AM/FM cassette car stereo in my Duster and somebody cut 6x9" ovals in the side panels in the back so I put my brother's old Sparkomatics in.

Those narrow channels opened into the trunk and there were holes in the rear shelf (including a 8" circlular one in the center and I covered it some.

BOOM. I butchered the door panels to add door speakers but it didn't work well, cracking the wires...no conduit!

Still, seven watts, if you were LUCKY, did the trick!

I had a Pioneer KP-500 in my Civic and Accord hatchbacks, and built small box speakers for them. Later I added a Fosgate booster amp which pumped twenty watts and sounded clean. I still have it all here and there, and the Pioneer is still an awesome tuner.

 

[laatsch55]

"Supertuner" series??