First post here!
Looks like there is a lot of info about the SP14.
I’ve wanted to build one of these for a long time, and finally got the resources together to get a kit.
I ordered the kit without the chassis, as I wanted to build my own - plus I wanted to try to save some $$$’s
I’m getting a LOT of noise out of this…
All the voltages are as they should be.
B+ is 276vdc
H+/H- is 6.13 and 5.87
Voltage drops from 313 to 276 across D13 (both sides…)
6.43vac on heater from transformer
I have checked, double and triple checked the wires from all RCA inputs/outputs. The ground bus and all the connections to that, the ground to the circuit board from the bus. I’ve gone over the input selector, and all the wires coming and going from that. All the connections from the selector, through to the gain and volume controls. The output from the volume to the board, and ground wire are as outlined in the instructions.
I did not install the tape switch, and ran the wires straight from selector to the gain pots.
There are two things I changed as far as the power supply goes. I used an old school toggle switch in place of the power switch that came with the kit. And I accidentally reversed the red and black primaries to the transformers from a hot/neutral perspective. But I don’t think the transformers care about hot/neutral?
The noise is the same regardless of gain/volume settings. It’s the same in both channels. It gradually comes up in volume as the unit powers up. As soon as it’s powered off, it disappears but music keeps playing until it fades away.
The noise is the same, albeit with different volumes, if I run it into my DIY Hiraga Super 30 Class A SS amp, or my DIYAudio VFet SE SS amp.
I took a measurement of the frequency output, but can’t seem to upload the photo?
Thank you for taking the time to read through this, any help would be greatly appreciated!