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SpiderII 15 Watt Amp IC question

Started by pudge211, November 30, 2014, 01:40:21 PM

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pudge211

I am using a DMM and I am using the black to ground. These are my readings.

H1+ is 20.3+
H2- is 20.3-

C35 is 20.3+
C36 is 20.3+

C31 is 9.4-
C32 is 9.4+

Speaker is dead. no reading and no sound.

Are these numbers good or bad and what's my next move?

Roly

Numbers are good.

Next step, fit new power amp IC and power up via a Limiting Lamp.

If the voltage on the chip output is within 0.1V of ground you can cobble on whatever speaker you have to hand for a functional test.
If you say theory and practice don't agree you haven't applied enough theory.

pudge211

Excellent..........  I will post back in acouple weeks. I just called the supplier for the the chip and speaker to find out why I haven't gotten a shipped notice and I am being told they are special order parts and they are waiting on them from Line 6 and it will most likely be 2-3 wks from the original order date. 

pudge211

 :dbtu: I installed the Amp IC today. Used a DMM to make sure no continuity between IC and chassis, plugged amp into test lamp and a temporary 6" speaker I knew was good and ..........NO FIRE!!!!. HUGE thanks to Roly and Doc for the help. As soon as I get the replacement speaker in from back order I will be 100% good to go.


Thanks Again!!!!
Joe

Roly

If you say theory and practice don't agree you haven't applied enough theory.

DrGonz78

Yup sometimes those chips just fail and burn up. Glad you got it all back in working order!!  :dbtu:
"A person who never made a mistake never tried anything new." -Albert Einstein

J M Fahey

#21
Just a (sad)  sidenote: last month TDA2050 were pulled from production, stock (over 1000)  dried at Digikey in a couple hours and doubless everywhere else.

Not to worry , EBay and dubious "suppliers" jumped to offer questionable chips ... which under test (and prying open with a crowbar)  showed to be relabelled TDA2030   :grr

So let buyer beware   :trouble

In a 15W amp, a TDA2030 is fine , but not in a larger one (18/20/25W or bridged 40/50W such as ampeg's 50W Bass amp) .

Authentic LM1875 is still  widely available and pin compatible, so I guess it's today's largest option in 5 leg TO220 case.

See it for yourself, both are labelled TDA2050   :duh


pudge211

Thanks for the info J M. I did find that info on the relabeled 2030's when I found my 2050 went into meltdown and that is why I went to Line6 Direct to get a replacement. You can find 2050's for as low as a $1 each on eBay right now and there are a lot of sellers. I bought the amp used and for all I know it could have had a chip replaced already. I'm hoping that by getting it directly from line 6 I won't have an issue. Time will tell.

tonyharker

Its not unknown for even reputable companies to unknowingly buy fakes.  The only safe place is the manufacturer of the device.