Lafayette Echo Verb II Noise

[plexi50]

I have a nice clean Lafayette echo verb II unit that has a lot of white noise. I have replaced all the electrolytics and it is 50% quieter but too much white noise persists. There are 4 green .1 50V film or poly caps that i have not yet replaced. Does anyone have any knowledge about these echo verbs? The reverb sounds decent and all the pots and inputs are functional

[plexi50]

I have changed all of the electrolytic capacitors and all of the .1 50V tone caps on this board. Still has noise. I have found that many of the carbon comp resistors have strayed very far from there original part values. Not to mention some of them look swelled up (fat) and look weathered. I will be replacing all of the resistors on wednesday and report back with my findings.

[gmoon]

Watching with some interest. I've got the first Echo Verb unit (cosmetically a "3").

It works OK, although it would be better "toned down." And the bypass signal degrades when the reverb is set over halfway, so I've also considered replacing the caps...

[plexi50]

Well i got all the resistors changed out this morning. No change. Still white hiss noise. Im looking at the power supply filtering caps again. I just replaced them 2 weeks ago so i doubt that is the problem. Im starting to suspect the 2SB347 germanium tranny. I hear they can hiss and make noise if they are bad or leaking. I tried an NOS AC128 but got the same hiss results. This little bugger is bugging me* 

[plexi50]

these units are known to have some white noise / hum

I found this statement online in the les paul forum

Now i have since replaced all the C828 transistors (5) of them and my unit sounds very quiet now and sounds pretty cool

But
There is still a small hum when the reverb pot is increased. Knowing that these units are reported to have some white noise or hum out of the box when new i am looking to fix this issue. I have the Echo Verb schematic but not the Echo Verb II schematic. Ironically i have the Echo Verb II Lafayette box that it came in when new but no schematic. I have to do some thinking when my brain turns on again. I dont see there being a PS cap filter problem with (2) new 470uf 35VDC capacitors on board, But could the original rectifier diode be leaking and cause this slight hum i am hearing?  White noise is another issue that is in the send i believe as when you have no signal applied the rumbling of the reverb return is nice and clear. Whatcha do ya think?

[plexi50]

Well from what i have experienced is that the C828 transistors were the cause of the of the slight hiss that i was experiencing. I just finished repairing another one and it is very quiet. I also installed an XLR input for microphone (harp players). It needed all C828 and small electrolytics. Now i have two of them. Neat little reverb units/

[smilan]

Hi plexi50,
I saw that you have the schematic for the echoverb 1.
I'm having some problems fixing my unit and I would appreciate if you can send me a copy of the schematic.
The main two problems are:
1. There's a strong distortion when I plug a guitar to both instrument and mic inputs.
2. There's strong hum noise while turning up the reverb pot.
I've already replaced the four electrolytic caps, replaced the filtering diode with diode bridge, replaced the four transistors with new ones and nothing seems to make any difference.
At this point I don't know what else should I do? (replacing the 4 green .1 50V caps and all the resistors?) .
Any suggestions?