sound issues on Amiga 4000

[sovietconscript]

i've been working on getting my A4000 running and its mostly ok now except i'm having sound issues. my first guess is bad caps or a monitor issue but I wanted to run it across people here first

my setup is
NTSC amiga 4000
OS 3.9 and boing bag 1,2 (no rom update)
amigakit 4gb CF hard drive
2 MB chip RAM
24MB FAST RAM
(16MB RAM on MB, 8MB on GVP A4000 scsi zoro expansion card)
monitor is a commodore 1040S

the issue seems to be with missing sounds or timing, i'll give a few examples

It came from the desert - no speech during the intro but the music does play (i pulled the CF hard drive and ran it on WinUAE on my PC and the intro speech works fine)

Elite - music at the begining is missing notes, also when you start the game you get no sound effects from the lasers unless your firing at the space station then they make a sound, otherwise nothing

every one in awhile i'll also get a video issue with a yellow tint coming over the display so maybe the sound/video issues could be the monitor?

the battery in the Amiga did have a very minor leak when i purchased it but I cleaned it up and there appears to be no damage.

any idea or should I start seeking someone to recap the board?

[roy bates]

you could load up a tracker program and play a mod then mess with the sliders to see if a channel can be heard.or turn o of channels to see if it maes any difference.

or check the phono sockets and plugs and wiring to the monitor or check the lead on an amplifier to see if still plays.

[Amiga1992]

Seems like you are missing a channel. Plug just one audio cable for mono and see what happens. Maybe it's just the audio connector which has a cold solder joint or crack.The video tinting definitely could hint at a cold solder joint. Are you using rgb or composite?

[sovietconscript]

RGB

ok, so I tried using a diffrent RCA cable for sound with no effect, then i tried disconnecting one or the other to see the effect. if I use only the red RCA jack for sound i get nothing at all (and yes i'm plugging into the red audio jack not the red chroma jack) but when I simply have the white RCA jack in it sound correct but it seems like one channel is vairy faint. for instance using mono via the white RCA jack i can barely hear the speech intro to "It Came From the Desert" where as before I couldnt hear it at all. Elite sound almost correct except some notes are faint in the intro music, lasers sound effects are fine now with that method though.

I hooked up my laserdisc player to the monitor (it was the closest thing to it that worked) and same effect, no sound at all through the red RCA jack. seems like a red jack issues with the monitor? i don't have any rca speakers at the moment or a rca to 1/8 jack so i cant test the jack on the amiga.

[FOL]

Originally Posted by sovietconscript

RGB

ok, so I tried using a diffrent RCA cable for sound with no effect, then i tried disconnecting one or the other to see the effect. if I use only the red RCA jack for sound i get nothing at all (and yes i'm plugging into the red audio jack not the red chroma jack) but when I simply have the white RCA jack in it sound correct but it seems like one channel is vairy faint. for instance using mono via the white RCA jack i can barely hear the speech intro to "It Came From the Desert" where as before I couldnt hear it at all. Elite sound almost correct except some notes are faint in the intro music, lasers sound effects are fine now with that method though.

I hooked up my laserdisc player to the monitor (it was the closest thing to it that worked) and same effect, no sound at all through the red RCA jack. seems like a red jack issues with the monitor? i don't have any rca speakers at the moment or a rca to 1/8 jack so i cant test the jack on the amiga.

If its doing it on both A4000 and laser disc, then has to be lead or monitor your using.

[sovietconscript]

well, yhea. i suppose id rather have a bum monitor then a messed up motherboard. well i'll just have to keep an eye out for a new one or use seperate speakers.

[roy bates]

ive never heard of a 1040s do you mean 1084s?


you could always get someone to have a look at the monitor.

[sovietconscript]

Originally Posted by roy bates

ive never heard of a 1040s do you mean 1084s?


you could always get someone to have a look at the monitor.

ha, your right. its a 1084s

I could, not sure if it would be worth the effort and cost. I don't particularly want to ship it and i don't know any amiga monitor experts in the area. i have some limited soldering experence if its a real simple fix.

[Amiga1992]

Sounds like your monitor is the problem. Throw it away. Better get an RGB to SCART cable for a modern TV or something like that.

[8bitbubsy]

Originally Posted by Akira

Sounds like your monitor is the problem. Throw it away. Better get an RGB to SCART cable for a modern TV or something like that.

You never throw away a 1084S! It's a good monitor for Amigas, and even as a gaming monitor for retro systems like C64, SNES and so on. The DAC and speakers on the 1084S are crappy anyways, plug in some external speakers.

[Jope]

There is no DAC in the 1084S, it is fully analogue. Maybe you're thinking about the amplifier.