Any suggest about cdrom audio out?

[piemmeweb]

Hello, I connected the cdrom audio-out to the audio-in on my amiga 4000 mainboard but the audio volume is very low, when play an audio-cd i need to up the volume to the end... My real problem is when play CD32 games: some of those have audiotracks + fx , then fx are high volume when audio tracks are low volume... I'm sorry for my bad english, I hope you understand what I'm telling and what's the matter

I'm thinking to add a simple audio preamplifier between cd audio auto and mb audio in (1 npn transistor at last, the pcb is smaller about 2 x 3 cm.)

any suggest about or other solutions?
many thanks!

[s2325]

Have you tried connecting earphones to the cd-rom?

[piemmeweb]

Originally Posted by s2325

Have you tried connecting earphones to the cd-rom?

my cdrom have not the earphone output or the volume control, I connected the 4-way cable

[Zetr0]

@plemmeweb

this is strangem, normally the CDRom has a higher output than that of the native Amiga Audio, usually the complaint is the other way around.

could you inspect *and take pictures* of the CD/AUX audio plug in and its surrounding capacitors.

The reason I mention this is that these capacitors are notorious for leaking and damanging A4000 motherboards

[piemmeweb]

Originally Posted by Zetr0

@plemmeweb

this is strangem, normally the CDRom has a higher output than that of the native Amiga Audio, usually the complaint is the other way around.

could you inspect *and take pictures* of the CD/AUX audio plug in and its surrounding capacitors.

The reason I mention this is that these capacitors are notorious for leaking and damanging A4000 motherboards

Hello Zetro, I know about capacitors, but amiga audio output have no problems, the caps are in working order yet, no leakage, but I will replace they to be sure.

thank you

[rkauer]

As a last resort, cut the GND wire(s) from the 4way connector and hear the difference.

[piemmeweb]

Originally Posted by rkauer

As a last resort, cut the GND wire(s) from the 4way connector and hear the difference.

Why about gnd wire?

[rkauer]

Sometimes the GND wire make a ground loop.

[piemmeweb]

Originally Posted by rkauer

As a last resort, cut the GND wire(s) from the 4way connector and hear the difference.

I tried but no difference.

is there a software that can regulate the amiga audio output (eg. the windows mixer)

[rkauer]

Nope.

[viddi]

I use this sound mixer on my A4000:

http://amigakit.leamancomputing.com/...roducts_id=485

A bit expensive, though...

[yaqube]

Originally Posted by piemmeweb

I connected the cdrom audio-out to the audio-in on my amiga 4000 mainboard but the audio volume is very low, when play an audio-cd i need to up the volume to the end...

I have had a glance at the schematics and it seems that the signal between the CD/DSP input connector and CINCH/RCA JACK output socket is attenuated by 12 dB.

I'm thinking to add a simple audio preamplifier between cd audio auto and mb audio in (1 npn transistor at last, the pcb is smaller about 2 x 3 cm.)

any suggest about or other solutions?
many thanks!

If you are familiar with SMD soldering you could replace R403A and R403E (10K) with 2K4 resistors. It should increase the voltage gain up to 0 dB but may cause increased load of the CD's audio output.

[piemmeweb]

Originally Posted by yaqube

I have had a glance at the schematics and it seems that the signal between the CD/DSP input connector and CINCH/RCA JACK output socket is attenuated by 12 dB.



If you are familiar with SMD soldering you could replace R403A and R403E (10K) with 2K4 resistors. It should increase the voltage gain up to 0 dB but may cause increased load of the CD's audio output.

where can i find the A4000 mb schematic?

[a_petri]

Originally Posted by piemmeweb

where can i find the A4000 mb schematic?

It's not the whole one, but the audio output part is here:

http://amiga.serveftp.net/images/Aud...atic-large.jpg