Just a hunch...
Does your PSU provide the -5v? The LM324 is not really a rail-to-rail opamp, so likely using +5 and -5 v for power, and thus needs -5v.
If you have a multimeter, check the continuity between pin 11 of LM324 and pin B5 on ISA edge connector.

Though maybe I'm wrong a the opamp is powered with +12v/-12v 😀
Can you post the photo of the bottom side?

Its an old AT PSU from 97.

If you have a multimeter, check the continuity between pin 11 of LM324 and pin B5 on ISA edge connector.

I do, but i never tried anthing like this on a running pc. The card is also not really accessible.
But at least this could be an explanation thanks.
Any other theories?

Can you post the photo of the bottom side?

Sure, maybe tomorrow.

Demolition-Man wrote on 2023-03-18, 18:57:

If you have a multimeter, check the continuity between pin 11 of LM324 and pin B5 on ISA edge connector.

I do, but i never tried anthing like this on a running pc. The card is also not really accessible.

You are not supposed to do that while the PC is running.
Take the card out, do the continuity check and put it back in.

You are not supposed to do that while the PC is running.
Take the card out, do the continuity check and put it back in.

Ok, got it.
(Also nur den Durchgang bei der ausgebauten Karte, prüfen. Von Pin 11 (Masse) des LM324 Verstärkers zum 5 . ISA Slot Kontakt auf der Oberseite, -5V, richtig?)

That's doable.

There's a connection, its beeping.

Ok, so now is the time to measure if the -5v voltage is ok or not. Typically -5v is not needed anywhere, so you might not even know if it's there or not until you find some card that depends on it.

If it's present on the white wire in AT connector J9 (between 2 blacks and 3 reds), then probably you should carefully measure the voltage on the pin B5 of any isa connector to see if it's delivered. Very carefully to not slip and not short -5v to anything else nearby.

If -5v is there, then it's safe to assume LM324 is bad and should be replaced. It's a very common part.
There is also marginal possibility that some SMD component cracked when the card was bent being stored carelessly.

Thank you, but i think this is a little bit too much for me.
I am so unbeliveable bad in soldering, but good on the short circuit part. 😉
Maybe there is no issue and its just the worst sound card ever made. (kidding)

I will ask in the German DOS forums if someone can help me with testing and repairing.

I can really recommend the chip combination (ALS100 +LS262). the card behaves exactly like a OPL3 Soundblaster 16,
with the exception of the bug-free midi, and the possibility of playing SB Pro sound in stereo. it's actually great for DOS gaming.

Alternatively, you can also buy an power supply tester, however it's made for ATX mostly.

Then, there's still the possibility of getting a POST card for ISA/PCI..
Some models have LEDs for the voltages.
They lid up if a voltage is present on the corresponding pin.

Source: https://commons.wikimedia.org/wiki/File:POST_ … IMGP6655_wp.jpg

Viel Glück. 🙂🤞

Sometimes the problem is the jack connector - some play well at full push, others at partial ejection, probably depending on the pitch of the contacts on the jack pin and in the card slot?

Sometimes the problem is the jack connector - some play well at full push, others at partial ejection, probably depending on the pitch of the contacts on the jack pin and in the card slot?

Interessting, but i tried 2 speakers and my headphones, always the same result. BTW i`m not that old (38) and have excellent hearing.

I still dont get it, one of my other cards: Sound Galaxy Pro 16III-3D PNP has, as I had already mentioned, 2 outputs. I always have to use the amplifed one. I have to turn down the mixer volume, and
can only use 1/5 of the volume knob on the speakers. A little bit to powerfull or "loud", but for what is the second output used or needed if not for powered speakers?
Too quiet or to loud, unlikly but possible, maybe my speakers and headphone are simply inappropriate for these old sound cards?

I found a affordable SB16 OPL3 card. (CT2230, MCD, with 1730-A). I hope it works fine and fits in in this special pc case. I already have a one (CT2910) on permanent loan from a friend, but finally
getinng my own SB16 OPL3 Card is fine by me. 😀
The two known problems: SB Pro in mono, but there schould be always an SB16 Option in my late DOS Game, and the HNB.:With UNISOUND i could use one of the other cards at the same time for MIDI
if needed.

DOS sound cards, a topic in itself... No problem finding the optimal graphics card for later DOS, get one from S3. Thats easy, but sound cards...^^

Edit:

Alternatively, you can also buy an power supply tester, however it's made for ATX mostly.

Any recommendation for the purchase in Germany? Most cards i find are junk from aliexpress. And without -5V.
The other voltages are ok, the mainboard is a Tyan S1590S Super Socket 7 Board with software to monitor the voltages.

Huh, I was searching for ALS100 + quiet and this thread came up - we have the same card! This is the MGYPRO16PNP- or Pro16PNP- card with the ALS100 on it and an 'LS262' chip for OPL3.
It's so quiet in fact that I initially thought it was just completely broken - like even with everything turned all the way up it was just barely audible and this is on a system that has a working -5v rail.

Tracking it around, the card design is honestly pretty bad - looks like in the other thread you found a mostly better ALS100 card. This one has a mono line-in and the +5VA analogue audio power is just sourced directly from the 5v line. What was breaking my card is that you see in the corner of the card there's an "L5" which should be an inductor but it's populated with a 10ohm resistor instead, same as yours.
I bypassed that with a wire jumper and the card then started sounding normal, still pretty quiet and I'm not sure the op-amp (LM324) is set up right or even up to the task, but it's now sounding pretty good.

My theory is that the resistor was operating as a current limiter instead of a wire link / inductor and the power available to the op-amp and ALS100 chip on the +5VA rail was way too low to get a decent sound output. I found this initially by checking the + (+5VA) and - (-5V) of the op-amp which was at something like 7 volts instead of the around 10 volts difference it should be.

I went a step further and put a 5v linear regulator running off of the 12v line to improve the sound quality too. By pulling that resistor out of the way the +5VA rail is no longer sourced from the computer's 5v rail and instead uses the regulator's output. 😀
Still a bit quiet in some games but working much better now.

Thermalwrong wrote on 2023-09-24, 17:34:

My theory is that the resistor was operating as a current limiter instead of a wire link / inductor and the power available to the op-amp and ALS100 chip on the +5VA rail was way too low to get a decent sound output. I found this initially by checking the + (+5VA) and - (-5V) of the op-amp which was at something like 7 volts instead of the around 10 volts difference it should be.

I went a step further and put a 5v linear regulator running off of the 12v line to improve the sound quality too. By pulling that resistor out of the way the +5VA rail is no longer sourced from the computer's 5v rail and instead uses the regulator's output. 😀
Still a bit quiet in some games but working much better now.

Sorry, but those cards were sold at a time when there was a transition from amplified output to line level output.
Older soundcards used amplified output that devlivered enough power to make headphones and even some passive speakers to sound loud.
Newer cards, especially not the first PCI ones, did not have any more amplified output.

Cards with line level output lacked of an amplfier and therefore were cheaper to produce.
ALS based cards were in some of the cheapest category therefore they needed external speakers with builtin amplifier.

Common mistake, you bought an ASMR sound card.

Disruptor wrote on 2023-09-24, 18:35:

Sorry, but those cards were sold at a time when there was a transition from amplified output to line level output. Older soundca […]
Show full quote

Thermalwrong wrote on 2023-09-24, 17:34:

My theory is that the resistor was operating as a current limiter instead of a wire link / inductor and the power available to the op-amp and ALS100 chip on the +5VA rail was way too low to get a decent sound output. I found this initially by checking the + (+5VA) and - (-5V) of the op-amp which was at something like 7 volts instead of the around 10 volts difference it should be.

I went a step further and put a 5v linear regulator running off of the 12v line to improve the sound quality too. By pulling that resistor out of the way the +5VA rail is no longer sourced from the computer's 5v rail and instead uses the regulator's output. 😀
Still a bit quiet in some games but working much better now.

Sorry, but those cards were sold at a time when there was a transition from amplified output to line level output.
Older soundcards used amplified output that devlivered enough power to make headphones and even some passive speakers to sound loud.
Newer cards, especially not the first PCI ones, did not have any more amplified output.

Cards with line level output lacked of an amplfier and therefore were cheaper to produce.
ALS based cards were in some of the cheapest category therefore they needed external speakers with builtin amplifier.

I do most of my testing with a Bose Soundlink mini, so definitely amplified separately. Even with the amplifier my card made almost no sound with the volume on everything set to max

At this point I think I'm hitting the same problems covered in this thread: ALS120, ALS100 Plus audio fix ?
I'm expecting too much from this original ALS100 chip, my ALS100+ is working nicely and my ALS200 (same as ALS100+ basically) is slightly broken. But this ALS100 is just so quiet, even putting it through a quality op-amp / amplification section gives little benefit.
Anyway, swapping L5 for a linear voltage regulator, or a jumper wire gave a good improvement to volume on this particular card.

There are at least two versions of the ALS100 sound card with two outputs:
https://wiki.preterhuman.net/Avance_Logic_ALS100_Pro16_PNP
This version and the Pro16PNP-4.
If you are looking for an amplifier variant you will find it there.
I wanted to install this sound card in my Compaq Prolinea 5120, but ran into compatibility problems with booth ALS100 cards. (Only my card with ESS 1868F chip works completely) Otherwise I'm just on the Sound Blaster trip with the other retro PCs 😉