Unable to configure H8000A analog 3-4

[sean.e]

I feel like I must be missing something obvious.  I am simply trying to get audio to pass through analog 1-4.  No problem getting analog 1-2 working, but having great trouble with 3-4.

 

Here is the routing I’m using for tests (via the front panel):

analog in 1-4 to IN 1-4

nothing to DSP A in

nothing to DSP B in

analog in 1-4 to Analog out 1-4

 

With meter source set to inputs, meters 3-4 show nothing unless bypassed (system relay).

With meter source set to outputs, meters 3-4 show nothing unless bypassed (system relay).

No sound from analog out 3-4 unless bypassed (system relay).

Bypass modes other than system relay are the same as no bypass (resulting in no sound from 3-4).

Should I be able to go straight from analog in 3-4 to analog out 3-4 without pressing the bypass button?  1-2 work as I expect.

Or do 3-4 need to be enabled somewhere that I’m forgetting?

Any chance that a hardware connection for the analog 3-4 i/o is independent of 1-2 and needs to be reconnected/reseated?

 

[nickrose]

Hi Sean

Looks like you have a hardware issue – this ought to work without doing anything unusual.

First thing to try is to remove the lid and reseat the ribbons going to the top audio board.

If that fails, there is one socketed chip on that top board. Give that a wiggle.

If these don't do it, it may have to come home. Let's hope not.

[sean.e]

I don’t know which step fixed it, but I’ve got LEDs lit up on analog 3-4 for both input and output (without being in bypass).

I completely removed both ribbon cables after clearing out the hot glue (?) from the board connectors — the glue gave way pretty easily. 

I reseated both ends of each cable several times to remove any possible oxidation. 

I didn’t remove the audio chips but gave them a good press all the way around (1 audio on the daughterboard, 1 audio on the main board and and another on the main board).

Thanks

[sean.e]

That treatment lasted about 8 years.  I had to try it again last night because less than 24 hours after it had been working fine, it stopped receiving audio — both analog and AES.  Reseating all 4 I/O board ribbon cable connections brought it back to life. 🎉

[Fender17]

I see, so if RCA SPDIF on my Eclipse seems not to work, it might be possibly fixed in a simmilar way.

[sean.e]

If the RCA SPDIF i/o is internally connected via ribbon cables, a similar fix is a possibility.

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