Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.

Topics - matthias

Pages: [1]
Looking around for information on Interstage Transformers I found this.
Figured I'd share it here...

Amplifier Discussion / Trace Elliot GP7SM 200...
« on: December 02, 2014, 10:13:54 AM »
I have this amp opened up and am looking for a PA Schematic.
Chassis was QC'd in 1994
It is not either of the PA boards covered in the GP7 150-300W manual.
Although it is very similar to the Mosfet Power Board...Designators are different, values vary, and...
I do have a request in at Trace Elliot via E-mail...but no response as of yet.

Amplifier Discussion / Earth Sound Research
« on: August 05, 2006, 04:35:41 PM »

Amplifier Discussion / Parallel filter caps
« on: July 19, 2006, 01:43:32 PM »
Hey Forumites,
I'm re-capping my Slave and I ended up going with a Bank of capacitors to cover the needed value,
Well, I got into a conversation about it with this old timer at my work (not electronics related), He grabed a bar napkin and drew up something like this:

Now this is somewhat confusing to me because I thought that Selection C was the way to go.
Selection A kind of makes some sense but..............Selection B just seems out there.
He stands by what he says but I Just don't trust it, He is the know it all type who is "never wrong" if you know what I mean. help me out here is this guy just in some "parallel reality" or is this guy really dropping some Phat knowledge on me?

Amplifier Discussion / matched power transistors......
« on: July 16, 2006, 03:23:05 PM »
I've got a question!
I have a Sunn Concert Slave head, sounded killer by the way!
Blah blah blah, long story short,
3 of the 5 power transistors have failed.
When testing them I noticed that 3 were 3055's and 2 were HEP704
the 3055's had #'s hand written on them, 86 and 87.
the HEP704 were not.
I'm wondering if these numbers represented thier original voltage drop? as in .86V or .87V.
But then on testing a known good (as in new) 3055, the voltage drop is around .5+V
one 704 and one 3055 survived.
NTE says that 3055 is a work alike for 704.
these transistors are all transformer coupled.
Do these need to be matched?
by what parameters are they matched?
Is there a method by which I can match a set my self?
here is a schem that seems to work, poweramp only:
Previous schems I posted were wrong, sorry.

Amplifier Discussion / Crate CR-212.....HUMMMMM
« on: July 09, 2006, 12:01:31 AM »
well, first off ...............
Hello. I've been looking for a place like this, although this seems more on the building side but I'm sure that some of you are great at trouble shooting  failures. If this is absolutely the wrong place for this post, just say. and/or point me to another SS forum, that would be great.
So, here goes.
I have this Crate CR-212 and it Hums, bad.
The hum is still there and unaffected with all pots at zero, same volume as when all knobs dimed.
I've checked the ground
I've replaced the input jack for the 0db and shorted the proper traces for the -6db
I've replaced the filter caps,
and I've replaced the rectifier diodes.
the hum is in the realm of a Baritone low C.
Where to next?

Pages: [1]