Orion 225-HCCA Repair ?

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Hello !
Have a Gen 1 225 HCCA with very weak output.
a 40hz test tone distorts very easy and only pulls approx 2amps @13.8v. 8ohm stereo.
It looks to be recapped everywhere (fresh solder)
Any ideas? Anyone repair these here?
Amp is very clean for it's age so I'd say it's worth salvaging.

Thanks!

 

[Perry Babin]

http://www.bcae1.com/temp/orionampclamps.swf

If you have to remove the clamps, refer to the diagram above.

Do you have a scope?

What is the DC voltage on the emitter resistors?

 

[Loaded]

Hi,
No scope
Voltage shows 17.49v

 

[Loaded]

Sorry for the dupe thread. Should know better not to use the mobile to post.

 

[Perry Babin]

18v is about right for rail voltage.

Does that voltage drop significantly when you drive the amp into a speaker load?

 

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Voltage drops to 17.2v when distorted.
I noticed the voltage is + on the first 3 resistors (per side) from the RCA input side. Then after that the resistors down the line are - 17.4v. Normal?
Thanks,

 

[Perry Babin]

± voltage is normal.

Measure the AC voltage across the speaker terminals when it starts to distort.

This amp was made to drive 1/2 ohm per channel. It won't make much more power than a standard head unit into the 8 ohm load.

 

[Loaded]

That is a great point. I have 4 dual 4ohm VC 8" woofers. I'll wire them up and give this little guy a proper test.

Any benefit to bridging? Looks to make the same power at the specified loads for stereo/mono.

 

[Perry Babin]

Bridging can be necessary to get full power if you don't have the right ohm load for running in stereo.