trinityamps.com

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sorry...they were...here they are again...

https://www.dropbox.com/s/lx0akegia9ddv ... 064758.jpg

https://www.dropbox.com/s/jxrk5xmwwtsut ... 064805.jpg

https://www.dropbox.com/s/oo4k0xrd251l1 ... 064811.jpg

https://www.dropbox.com/s/esy02pr1cs9cp ... 064901.jpg

i've re-tightened grounds...the caps look in good condition...i know my voltages were a little low IIRC but i don't think that would be causing this hiss...

i've tried around town...no one carried metal oxide resistors...so i'll order some and put them on the grids and see if that helps...

as a follow up...i tested all the caps...i don't know if it has anything to do with the bleed resistor but...
the caps mostly had high numbers...except for C2 (.68uF), C16 (220uF), and C10 (220uF)
upon removal i got anywhere from 15-25k ohm readings...but back on the board, nothing...
while in the circuit, R29 was only reading 250k ohm...outside the circuit it was bang on...

i'm truly at a loss...everything appears to be grounded right...unless the above is a sign of an issue...

i re-flowed the solder on V1-3 on all the pins...as well as taking moving the lead from R15 to pin 3 of V3 instead of pin 8 to keep it away from the heater wires,,,

its hiss and 120hz...and its killing me!! i'm starting to pull hair out!

Did you disconnect one of the inputs from the normal channel as i don't see both 68 k resistors. and could we get a picture of the opposite of of the cascade switch

in an effort to stop the links expiring...here are the pictures attached

i tested the caps in the circuit using a multi-meter...if they are to have a min ohm reading of 15k per the manual...C2 and C16 had none...i took them out of the circuit and tested them...they read 15-25k ohm...which would mean they are good...but i guess that means that i have a low resistance load pulling current...its a great note in the manual, but i don't understand what that means...unless the bleed resistor i installed back at the main cap is causing that...what does that mean?

When reading ohms on a multimeter it puts a voltage across what ever your reading and calculates a resistance which is great for resistors. Or dead shorts which would be zero resistance. In the case of capacitors when you a apply voltage to them they tend to charge giving you some resistance value. which yes would mean that the are good. What you wouldn't want to see is a dead short on a cap as that would indicate a bad cap.

That being said i don't think you have bad cap's.

Looks like the cascade is wired up correctly.

At this point still thinking is a grounding problem by your description of kicking in the boost cap. Looking at the connection I can see on the big copper ground buss. The solder looks too clumpy. (should have flowed all around not clumped up on top) Which would mean the ground buss didn't get hot enough when soldered. I know from doing mine it takes more time to heat up with my 35w iron than it does with all the other component and small switch connections. You might want to re do those and the ones under the coax i cant see

One other thing is you have used the bolt mount on v1 standoff as a ground point. When i do that I tend to run a soild wire soldered to the standoff and go under the board and connect to the bus ground ( keeps the star preamp ground in tact)

thanks Saz

the manual says to test the cap that way...thts why i did...and why i asked about the loading...it mentions it, but then doesn't say if its bad or good, or what to do...

i'll re-flow the bus again...i understand exactly what you are saying...burned myself twice doing it...

i will do what you suggested about the ground point...didn't think it would be an issue, but i'll see what happens...