Some sound cards need -5V, but it's not a hard rule. It depends very much on the design of the card itself. Is the card set to output for speakers or line out? On the other side, what are you using to listen to the card?

Hi gdjacobs,
the output is for speakers. I've tried listening to it both with headphones and with speakers, no change in sound signature. BTW, it seems to play Wave a lot cleaner and louder as compared to MIDI - that's absolutely horrific.
This is the card: http://shrani.si/f/3A/gp/19XCqUJb/zvocnaess.jpg

ESS cards does not require -5 voltage. At least I've never seen one using it.

I really think you'll need an oscilloscope to properly diagnose this, but I'd certainly check voltages into the amp chip (the LM1877). Pin 14 should be +Vcc, pin 3 (and others) should be ground, pin 1 should be floating.

Try using ESSVOL to check and adjust volume levels. Their settings may just be completely off.

The Serpent Rider wrote:

ESS cards does not require -5 voltage. At least I've never seen one using it.

I suspect the reason for -5V is to permit the amplifiers to reach 0V when needed. I forgot the electrical term for it but almost all amplifiers have trouble when their output approaches the supply voltage so even if it claims to be capable of 0V, putting some space there can only help, IMO.

The amp on this board is capable of running in single ended mode. It'll have caps for bias removal, so it ultimately doesn't matter if the amp can do rail to rail or not.

It depends on how the card is designed.. if the MC3403 opamp uses -5v it could explain things.. if you post a photo of the back of your card we can verify that

I doubt it does require -5V. See the output decoupling caps.

Photo of back of card will reveal everything. Most stuff I see uses +/-12V, +/-5V is pretty uncommon.

Hi guys,
thank you for all the suggestions.

Here is the back of the card: http://shrani.si/f/1J/Q3/27GJoJuP/essback.jpg

I'll try playing with SETVOL and the other utilities some more tomorrow.

Regards

It doesn't appear to use either the -5V or -12V rails.

Update:
tried using these drivers, as suggested by the eBay seller I bought the card from (although it's supposed to work without any): http://vogonsdrivers.com/getfile.php?fileid=372
Here's what I get: http://shrani.si/f/1P/lS/4MCkrdva/essvol.jpg

Also tried disabling any devices that may be using conflicting resources, like parallel and serial ports in the BIOS.
Disabled both internal and external CPU cache.

No luck - the sound is still trash and too quiet.

However, if I run ESSVOL, it does say that it found an ess688 at address 220.
I'll now try editing the autoexec.bat and config.sys files to see if that has any effect on the volume at all.

ESSVOL has no effect on any volumes.
The same goes for changing /v and /s values in autoexec.bat
Trying to run SETVOL says that the card is not initialized or something along those lines.

Did you change capacitors?