Yeah that was my understanding as well but the internet is full of scary stories and conflicting into regarding tube amps.
I suspect it’s something in how I wired the transformers for triode mode but I will have to check it out.
Ok so here is what I have done so far:
-disconnected and reconnected OT wiring to board for triode mode
-verified ground on all speaker terminals and inputs/board
-checked signal with pilot light disconnected from 6.3v line
-checked source by using another source
-checked speakers by using different speakers
The result is the same. With the volume at full I can hear music emanating from the OTs and a faint distorted signal coming from the speakers. I’m not an expert but this tells me that the signal is making its way to the OTs but not getting to the speakers for some reason.
I again verified that B+ is at 445.
Any help would be greatly appreciated I’m running out of things to try.
-disconnected and reconnected OT wiring to board for triode mode
-verified ground on all speaker terminals and inputs/board
-checked signal with pilot light disconnected from 6.3v line
-checked source by using another source
-checked speakers by using different speakers
The result is the same. With the volume at full I can hear music emanating from the OTs and a faint distorted signal coming from the speakers. I’m not an expert but this tells me that the signal is making its way to the OTs but not getting to the speakers for some reason.
I again verified that B+ is at 445.
Any help would be greatly appreciated I’m running out of things to try.
I did not but that’s a good idea. In that case do I still need to ground the negative side or no?
Well gosh darn, it worked! In my quest for high end connectors it looks like the terminals i bought are way too thick and were choking the signal. I connected the test speakers directly and they sound great.
For now I spliced in some solid copper cable I had lying around and I’ll screw those into the banana plugs with the speaker wire. Will update later when I get it up into my main system.
For now I spliced in some solid copper cable I had lying around and I’ll screw those into the banana plugs with the speaker wire. Will update later when I get it up into my main system.
I actually think they were just too thick. The chassis is non-conductive but they were insulated anyway. I’ve never heard of an amp not being able to push a signal through a terminal but they were like 1.5” long bolts basically so who knows?
My chassis is 17x13, I used aluminum plates and 2” u channel and bolted it all together.
If I was doing it again I would mount the board underneath for safety, but mostly I’m just happy it works.
Looking at the photos I think it would be worth taking your DMM and checking for continuity between the speaker posts and ground just to be sure there is none.
Well I deleted the binding posts and just ran some wire out of the holes and connected the speaker wire directly, so it’s not an issue currently.
But if I’m looking at the drawings correctly the negative speaker cable/terminal needs to go to ground right?
Yes but only the negative and that is how I have mine wired. However I suspect the positive on yours may have also had some connection to ground. Also even on the negative side multiple paths to ground may cause problems with hum so it's good to verify both positive and negative.
Got it, thanks.
One thing I was wondering though was about the rectifier switch, when the switch is engaged is that tube or solid state? I’m assuming the board defaults to tube so switch off would be tube right?
This may or may not help, but here you go. See edit.
I am also using Edcor iron and have the same color codes.
Here is a hi res bottom picture. Triode wired. No feedback.
Input and output grounds are the black/white stiped wires. Grounding is done by George's wiring documentation in the SSE instructions.
Specifically this one
This works flawlessly.
**EDIT*
In the first picture the mains A/C wiring IS NOT wired in at all. Ignore that aspect completely.
I am also using Edcor iron and have the same color codes.
Here is a hi res bottom picture. Triode wired. No feedback.
Input and output grounds are the black/white stiped wires. Grounding is done by George's wiring documentation in the SSE instructions.
Specifically this one
This works flawlessly.
**EDIT*
In the first picture the mains A/C wiring IS NOT wired in at all. Ignore that aspect completely.
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Yep that’s how I had mine wired except my terminals have tabs on the end of the bolts for soldering/tab connectors. As soon as i bypasses them and went to straight wire it worked fine. Not really sure why other than they produced too much resistance.
Dayton Audio BPFI-G Fully Insulated Binding Post Banana Jack Pair Gold
Hmm good question I think i had both washers on the outside now that you mention it. The chassis is painted aluminum though so would it still matter?