4-slot board headphone jacks

mmsadda

Just buy my shit. Seriously. You can call me Susan
10 Year Member
Joined
Jan 20, 2009
Posts
3,067
I'm getting no sound out of either headphone jack on my four-slot board. I find it hard to imagine the headphone jacks are somehow blown, so I'm wondering if there's a switch that could have turned them off or something. Any thoughts as to what I should look into? I need a working jack to put a bass speakers in my cabinet, as it only has like 2"x3" speakers, and they get distorted with bass.
 

mmsadda

Just buy my shit. Seriously. You can call me Susan
10 Year Member
Joined
Jan 20, 2009
Posts
3,067
Ten people have read this already, and no one has any ideas to post? Is the board just plain broken and I'm a dumbass for even asking?
 

Xian Xi

JammaNationX,
15 Year Member
Joined
Dec 1, 2005
Posts
27,748
The two headphone jacks are driven by the same pair of caps, try tapping the sound before the cap and see if you hear anything, if you do then you need to change the caps.

Also make sure the volume is up and also don't check sound during attract mode as sometimes it's off.
 

mmsadda

Just buy my shit. Seriously. You can call me Susan
10 Year Member
Joined
Jan 20, 2009
Posts
3,067
Thank you, James! I'll go try that!
 

xiao_haozi

Avid Neo-Expert
Joined
Jan 22, 2009
Posts
1,977
Yeah just go into hardware mode to test... that way you can do the separate channels.

Could he maybe short the caps temporarily to test through the headphone jacks???
 

MKL

Basara's Blade Keeper
20 Year Member
Joined
Mar 8, 2002
Posts
3,686
The jacks J4 and J5 on the 4-slot (and 6-slot) aren't headphones jacks at all, i.e. they aren't like the jacks on the 2-slot. They're a low level output, so low actually that you can't hear anything if you plug headphones into them. The 6-slot manual says "LINE IN" which makes no sense and is probably a typo.

Here's the 4-slot audio circuit where you can see they have nothing to do with the headphones out, which is header J3:


Note that The 2-slot models with headphones jacks (MV2 and MV2F) lack the headphones header whereas the 2-slot model with the headphones header (MV2B) lacks the jacks.

Anyway, with a super easy mod you can turn J4 and J5 into actual headphones jacks:

 

xterc

n00b
Joined
Jul 22, 2017
Posts
39
Anyway, with a super easy mod you can turn J4 and J5 into actual headphones jacks:


I know this is an old thread, but I recently acquired a 4-slot and made the same mistake thinking J4 & J5 were headphone slots.

I could probably figure out the mod talked about above, but does anyone know where I can find the image that has been removed from the above post? I saw that GadgetUK made a similar mistake and video, I could potentially pause his video and make the mod from that.

I assume the ground is common, which is why only two wires were needed in the 'hack'.
 

GadgetUK

Ace Ghost Pilot
Joined
Sep 27, 2013
Posts
1,323
Yes, only left and right pins are needed as ground is common - which are the outer pins on the 4 pin white headphone output. You can just re-purpose one of the 3.5mm sockets like I did. Just check your left and right is the right way around using the sound test in the bios.
 

xterc

n00b
Joined
Jul 22, 2017
Posts
39
Yes, only left and right pins are needed as ground is common - which are the outer pins on the 4 pin white headphone output. You can just re-purpose one of the 3.5mm sockets like I did. Just check your left and right is the right way around using the sound test in the bios.

Thanks, will do! I do like your videos, very matter of fact and down to earth (re: no BS).
 

xterc

n00b
Joined
Jul 22, 2017
Posts
39
4 Slot Headphone Modification (thanks GadgetUK):
headphone_mod.jpg

Universe Bios 3.3 Installed (thanks Raz!)
4slotuni.jpg

Cleaned up and sprayed black.
4slot.jpg
 
Top