Unusual oscope results!

[Sguirrelfeather]

Was setting my buddy's new sub amp so he doesn't blow things up (he likes to fiddle when he doesn't understand what he's doing), and I began playing with the gain while watching both the DMM and o-scope. Rather than seeing the normal flattening of the sine wave when it begins to clip, I saw something WAYYY different. I don't even know what to call it. It's like there were little pulsing spikes of voltage on the down slope of the wave. I didn't think to take a pic, but I created a very poor rendition with MS Paint. lol

Anyone know what, why, how, etc??

View attachment 26556864

Click to read more...

 

[Boomin_tahoe 5,000+ posts]

Wow....I've never seen that before.

See if @Jeffdachef is around to help out.

 

[LosIsATool 5,000+ posts]

Distortion. What amp?

 

[Boomin_tahoe 5,000+ posts]

Distortion. What amp?

How? Please explain.

 

[The_Quiet_One 10+ year member]

Was the voltage noise observed in the entire down slope or was it only there in the top half of the slope?

 

[Sguirrelfeather]

Distortion. What amp?

Brand new CT Sounds T-2500

Was the voltage noise observed in the entire down slope or was it only there in the top half of the slope?

Honestly, I don't remember. I think it was only on the top half. I'll have to re-run the test to be sure. And this time I'll get a picture!

 

[Papermaker85 5,000+ posts]

Was setting my buddy's new sub amp so he doesn't blow things up (he likes to fiddle when he doesn't understand what he's doing), and I began playing with the gain while watching both the DMM and o-scope. Rather than seeing the normal flattening of the sine wave when it begins to clip, I saw something WAYYY different. I don't even know what to call it. It's like there were little pulsing spikes of voltage on the down slope of the wave. I didn't think to take a pic, but I created a very poor rendition with MS Paint. lol
Anyone know what, why, how, etc??

View attachment 26556864

noise

 

[Papermaker85 5,000+ posts]

send that junk back.

 

[hispls 5,000+ posts]

Brand new CT Sounds T-2500

I think I found the problem.

Is it there at all levels or just approaching clipping?

 

[LosIsATool 5,000+ posts]

I think I found the problem.
Is it there at all levels or just approaching clipping?

No not the alibaba special

 

[hispls 5,000+ posts]

No not the alibaba special

You can buy Zenon amps on Alibaba which are actually pretty solid as far as Far East offerings go. Still though, yeah, people think Sundown, IA, DD, etc. just charge more money for their amps because they're greedy or something.

The whole "you can't get something for nothing" is something I learned in high school so I guess I take it for granted.

 

[LosIsATool 5,000+ posts]

You can buy Zenon amps on Alibaba which are actually pretty solid as far as Far East offerings go. Still though, yeah, people think Sundown, IA, DD, etc. just charge more money for their amps because they're greedy or something.
The whole "you can't get something for nothing" is something I learned in high school so I guess I take it for granted.

The T line is china

 

[hispls 5,000+ posts]

The T line is china

Do they sell anything that isn't?

 

[LosIsATool 5,000+ posts]

Do they sell anything that isn't?

I don’t think so

 

[NSTALN 10+ year member]

Does the sign wave look like this with the engine running? Does it look different with the engine off? AC ripple bleeding into the signal path?