You should be plugging your speakers into line out or speaker out. Line in or microphone is for audio input into the sound card, not for listening. The SC-55 would connect to the line-in.

Are you sure you've identified the connections correctly? Some times the way they are labelled on the bracket can be confusing.

Some soundcards did/do support switching ports via software.
That feature had been exploited to turn the headphones into microphones to spy on users..

Shponglefan wrote on 2024-12-10, 18:04:

You should be plugging your speakers into line out or speaker out. Line in or microphone is for audio input into the sound card, not for listening. The SC-55 would connect to the line-in.

Are you sure you've identified the connections correctly? Some times the way they are labelled on the bracket can be confusing.

I thought at first I had misunderstood them. But working from left to right, there’s ‘something’ Game, which is a safe bet that it’s the serial port, then it’s Mic, ‘ine In’ (Line In) and then ‘dio Out’ (Audio Out).

Are you sure the bracket is original, and not transplanted from another card, because this card's bracket was lost to rust or just borrowed forever?

vstrakh wrote on 2024-12-10, 19:27:

Are you sure the bracket is original, and not transplanted from another card, because this card's bracket was lost to rust or just borrowed forever?

I have absolutely no idea, I'm afraid. It was bought second hand off eBay.

I've sent a message to the seller I bought it from, but whether they know or respond, we'll see.

From what I remember this is a Yamaha YMF-71x card, correct? In which case the bracket is likely original. The Audio Out would be on the top (right) of the bracket.

You should connect your speakers to the Audio Out (right side) of the card. If you're not getting audio output, then you need to check mixer settings, drivers, etc.

Shponglefan wrote on 2024-12-10, 23:13:

From what I remember this is a Yamaha YMF-71x card, correct?

In which case the bracket is likely original. The Audio Out would be on the top (right) of the bracket.

Therefore you should connect your speakers to the Audio Out. If you're not getting audio output, then you need to check mixer settings, drivers, etc.

Yeah, the Yamaha YMF-71x. And that pic is bang on to what mine is like.

Hmm. Okay, I'll try doing a bit of digging and experimenting. Short of uninstalling the drivers and re-installing them from scratch, I'm not sure what else I could do.

Does it actually sound "OK" at least through the MIC out and does it play in stereo ? Is the volume really low?

My gut feeling is that the card (probably the mixer on tbe chip, more specifically) suffered some odd damage which is causing this, somehow.

I don't see how a driver issue could cause this (you could try under DOS to be sure) and that Yamaha chip and card date back to before jack reassignment was a thing.

The only other thing that springs to mind is that this is an oddball variant of that card with a slightly different layout that was factory paired with the wrong backplate. That would very much be a longshot, though.

darry wrote on 2024-12-11, 00:03:

Does it actually sound "OK" at least through the MIC out and does it play in stereo ? Is the volume really low? […]
Show full quote

Does it actually sound "OK" at least through the MIC out and does it play in stereo ? Is the volume really low?

My gut feeling is that the card (probably the mixer on tbe chip, more specifically) suffered some odd damage which is causing this, somehow.

I don't see how a driver issue could cause this (you could try under DOS to be sure) and that Yamaha chip and card date back to before jack reassignment was a thing.

The only other thing that springs to mind is that this is an oddball variant of that card with a slightly different layout that was factory paired with the wrong backplate. That would very much be a longshot, though.

It’s possible it could have suffered some odd damage. It did look slightly bent/skewed when I first put it in. 🫢😅

But yeah, it sounds perfectly fine in the Mic input. It can have some distortion/crackling if the volume in the mixer is at maximum. The volume dial isn’t even up very much either.
But I’ll try testing it out under DOS tomorrow. I’ve experimented with the speakers and cables, but nothing works if it’s in anything else but Mic. I even tried just the two speakers on their own. I took some pics of the backs of the speakers to double check I’ve set things up right. I wondered if I needed to connect a Left and Right cable in Line 2, but couldn’t get anything different there. And yep - tried re-installing the drivers, but, nada.

I just hope when I finally get the SC-55 set up, and hook it to the Line In (or Audio Out), that it works. 😕

And I did try connecting the right speaker to In and Out, and the other cable in the opposite, and then into Audio Out and Line In, but no change.

DustyShinigami wrote on 2024-12-11, 00:21:

The attachment IMG_3907.jpeg is no longer available

You don't have anything connected to speaker input, but you have something connected to the output?

And I did try connecting the right speaker to In and Out, and the other cable in the opposite, and then into Audio Out and Line In, but no change.

There's a specific way speakers are supposed to be connected.

With the Yamaha speaker + sub combo, typically you would connect things as follows:

Soundcard Audio Output -> Subwoofer Line 1 Input
Subwoofer Line 1 Output -> Right Speaker Input
Right Speaker "To Left Speaker" Output -> Left Speaker "To Right Speaker" Input

Nevermind, this is for the YST-M10 speakers, while you have a different model.

Shponglefan wrote on 2024-12-11, 00:26:

You don't have anything connected to speaker input, but you have something connected to the output? […]
Show full quote

DustyShinigami wrote on 2024-12-11, 00:21:

The attachment IMG_3907.jpeg is no longer available

You don't have anything connected to speaker input, but you have something connected to the output?

And I did try connecting the right speaker to In and Out, and the other cable in the opposite, and then into Audio Out and Line In, but no change.

There's a specific way speakers are supposed to be connected.

With the Yamaha speaker + sub combo, typically you would connect things as follows:

Soundcard Audio Output -> Subwoofer Line 1 Input
Subwoofer Line 1 Output -> Right Speaker Input
Right Speaker "To Left Speaker" Output -> Left Speaker "To Right Speaker" Input

I think I did try both speaker inputs when I was experimenting. I’ll try following your suggestion, which I’m guessing is from a PDF manual…? Didn’t even think of checking that actually. 😅 It’s just a pity no paper manual came with it when I bought it. But I presume I have all the right cables.

I’ll go and find the PDF manual.

Shponglefan wrote on 2024-12-11, 00:26:

You don't have anything connected to speaker input, but you have something connected to the output? […]
Show full quote

DustyShinigami wrote on 2024-12-11, 00:21:

The attachment IMG_3907.jpeg is no longer available

You don't have anything connected to speaker input, but you have something connected to the output?

And I did try connecting the right speaker to In and Out, and the other cable in the opposite, and then into Audio Out and Line In, but no change.

There's a specific way speakers are supposed to be connected.

With the Yamaha speaker + sub combo, typically you would connect things as follows:

Soundcard Audio Output -> Subwoofer Line 1 Input
Subwoofer Line 1 Output -> Right Speaker Input
Right Speaker "To Left Speaker" Output -> Left Speaker "To Right Speaker" Input

Okay, studying the diagrams in the manual, I’m a bit confused with it. Your setup matches the right image, but that’s different to the left’s. And yet the speakers in the left image match the look of mine as well as the back. And yet that one mentions nothing about connecting the right speaker to the left one. 🤔

DustyShinigami wrote on 2024-12-11, 01:29:

Shponglefan wrote on 2024-12-11, 00:26:

You don't have anything connected to speaker input, but you have something connected to the output? […]
Show full quote

DustyShinigami wrote on 2024-12-11, 00:21:

The attachment IMG_3907.jpeg is no longer available

You don't have anything connected to speaker input, but you have something connected to the output?

And I did try connecting the right speaker to In and Out, and the other cable in the opposite, and then into Audio Out and Line In, but no change.

There's a specific way speakers are supposed to be connected.

With the Yamaha speaker + sub combo, typically you would connect things as follows:

Soundcard Audio Output -> Subwoofer Line 1 Input
Subwoofer Line 1 Output -> Right Speaker Input
Right Speaker "To Left Speaker" Output -> Left Speaker "To Right Speaker" Input

Okay, studying the diagrams in the manual, I’m a bit confused with it. Your setup matches the right image, but that’s different to the left’s. And yet the speakers in the left image match the look of mine as well as the back. And yet that one mentions nothing about connecting the right speaker to the left one. 🤔

The attachment IMG_3908.jpeg is no longer available

It looks like there are two different set ups depending on the speaker model. I have the YST-M10 speakers, which use the diagram on the right. But in your case, since you have the YST-M20DSP speakers, you would connect it via the set up on the left diagram.

Shponglefan wrote on 2024-12-11, 03:20:

DustyShinigami wrote on 2024-12-11, 01:29:

Shponglefan wrote on 2024-12-11, 00:26:

You don't have anything connected to speaker input, but you have something connected to the output? […]
Show full quote

You don't have anything connected to speaker input, but you have something connected to the output?

There's a specific way speakers are supposed to be connected.

With the Yamaha speaker + sub combo, typically you would connect things as follows:

Soundcard Audio Output -> Subwoofer Line 1 Input
Subwoofer Line 1 Output -> Right Speaker Input
Right Speaker "To Left Speaker" Output -> Left Speaker "To Right Speaker" Input

Okay, studying the diagrams in the manual, I’m a bit confused with it. Your setup matches the right image, but that’s different to the left’s. And yet the speakers in the left image match the look of mine as well as the back. And yet that one mentions nothing about connecting the right speaker to the left one. 🤔

The attachment IMG_3908.jpeg is no longer available

It looks like there are two different set ups depending on the speaker model. I have the YST-M10 speakers, which use the diagram on the right. But in your case, since you have the YST-M20DSP speakers, you would connect it via the set up on the left diagram.

Ahhh, gotcha. So you have more or less the same setup? Didn’t even process the speakers saying YST-M10 on the right. Strange the left one doesn’t say YST-M20DSP. Also, neither show the cable type that you plug into the right speaker to the left. An arrow comes from the one on the right, but there’s nothing like that for the left image.

Just tried setting it up based on the left image, but there’s no sound at all. Not even from the Mic port. Which tells me that something needs connecting to the Out of the Subwoofer, too. The left image doesn’t show that, but the right does.

I can’t help but wonder if I’m a cable short, too. I need to see if that manual lists the total number of cables there should be.

Yeah, this is all back to front. The diagrams in that manual are totally different to my setup. For audio to work for me, a cable has to go from the subwoofer’s output into the sound card. And into the Mic port. And a cable goes into the right speaker’s output into the subwoofer’s input. Putting anything into the right speaker’s Input 1 does nothing. No audio. 🤔

Very odd.

Audio connections are highly logical, and audio signals should flow in a specific way.

My recommendation is to take the subwoofer out of the equation. Connect the Audio Out from your sound card to the Input on your speakers.

If you don't get audio, then there is something wrong. Either with the sound card itself, the drivers, mixer settings, speakers (possibly a broken audio jack), or the audio cable itself.

At which point, I would try different hardware. Try testing the sound card (again, connected only to Audio Out) with different speakers. If they also don't work, then it's probably something to do with sound card or software (e.g. mixer settings). Likewise, test the speakers with a different audio device besides the sound card. Do they work? If yes, then it's not the speakers.

Basically you want to isolate what the problem really is. You do this by making things as simple as possible and swapping hardware to isolate the faulty component.

Shponglefan wrote on 2024-12-11, 16:48:

Audio connections are highly logical, and audio signals should flow in a specific way. […]
Show full quote

Audio connections are highly logical, and audio signals should flow in a specific way.

My recommendation is to take the subwoofer out of the equation. Connect the Audio Out from your sound card to the Input on your speakers.

If you don't get audio, then there is something wrong. Either with the sound card itself, the drivers, mixer settings, speakers (possibly a broken audio jack), or the audio cable itself.

At which point, I would try different hardware. Try testing the sound card (again, connected only to Audio Out) with different speakers. If they also don't work, then it's probably something to do with sound card or software (e.g. mixer settings). Likewise, test the speakers with a different audio device besides the sound card. Do they work? If yes, then it's not the speakers.

Basically you want to isolate what the problem really is. You do this by making things as simple as possible and swapping hardware to isolate the faulty component.

Okay, makes sense. And worth a shot. There are some spare modern speakers under the bed I can always try. I'm not sure what other drivers to try though. The set I first got working had a better volume mixer, which I asked about in this thread - Volume Control/Mixer for Yamaha OPL3 Sound Card - but I can't for the life of me find them anywhere. They worked, but I'm not sure how correct they are. The only ones I've had any luck with up to now are the current ones, which are 952343.

I did get a response from the seller on eBay and they're also none the wiser about the bracket.