Sega Master System - Low Audio Volume

[eric90000]

Hey,

I have an NTSC SMS mk1 that has pretty weak/quiet sounding audio. Compared to my other consoles (all connected to gscartsw and OSSC) it sounds much quieter. Is this normal on some mk1 Sega Master Systems?

I have already replaced all the capacitors and installed Tim Worthington's FM sound mod....even after this it sounds quieter than my Genesis, Famicom, SNES etc. It's not super quiet or anything, but I definitely have to crank my AV receiver higher when using the SMS.

Is it possible to increase the volume by inserting some sort of audio amp, or even change the sound chip?

Any help would be appreciated!

[ASDR]

Analog audio gain was added in a recent OSSC firmware, maybe you could make a profile for your SMS?

[mvsfan]

Ive had genesis systems that had a bad Audio Amplifier Chip. Usually though the sound just doesnt work at all on them.

could be something to look into though.

[eric90000]

Thanks for the feedback guys, in the short-term I'll make an OSSC profile with higher audio gain (that's cool I didn't realise that, cheers for the tip!).

I might try source a replacement audio chip and see if that makes a difference also.

[mvsfan]

You can test it in different spots by using a pair of powered speakers and hooking some probes up to them.

Ideally you want an alligator clip on the negative speaker input and a probe on the positive input.

then you clamp the negative to a good ground on the motherboard.

Put a game in the master system and boot it. Get yourself a pinout of the relevant audio chips. then you can use the probe to listen to the audio outputs on the chips. If you hear nice clear sound, the chip is good. if you dont, its not.
Pin 9 on the CXA1145 should be your audio output.

[eric90000]

You can test it in different spots by using a pair of powered speakers and hooking some probes up to them.

Ideally you want an alligator clip on the negative speaker input and a probe on the positive input.

then you clamp the negative to a good ground on the motherboard.

Put a game in the master system and boot it. Get yourself a pinout of the relevant audio chips. then you can use the probe to listen to the audio outputs on the chips. If you hear nice clear sound, the chip is good. if you dont, its not.
Pin 9 on the CXA1145 should be your audio output.

I somehow missed this comment. Thank you for the advice, I'll give this a go soon. I was playing the Master System today and it reminded me how low the audio volume is on this.

I wonder how easy it is to source the CXA1145 chips these days...

[Lawfer]

Is the Master System a good console to invest into? I don't see many people recommanding it or talking about it.

[mvsfan]

theres quite a few good games on it. Hang on, Gradius, rtype, shinobi, golden axe warrior, etc etc.

yeah its worth getting. you could also get a powerbase Mini Fm converter and play the games on your genesis too. the master system controllers even work on the genesis they just plug right in.

[Ikaruga11]

Is the Master System a good console to invest into? I don't see many people recommanding it or talking about it.

That's what I was wondering too. The Sega Mega Drive/Genesis is backwards compatible with Master System games. You can use the Power Base Converter add-on to play your Master System cartridges, or simply play Master System games with the Mega Everdrive without the Power Base Converter.

[Gara]

Is the Master System a good console to invest into? I don't see many people recommanding it or talking about it.

It's a fun system. It kinda falls into that same area as the PSX. The SMS has a few different ways to get access to the library so the original system gets largely ignored.

Nt Mini - fpga sms core is pretty good. Not super polished. No light gun or other accessory support. Fm audio is present but is not an exact replica. It is a close approximation.

Fm mini Genesis - a true Yamaha fm audio chip and not a bad solution. Master everdrive in game menu does not work so no save states.

Mega everdrive x7 - sms emulation a very nice bonus for owners. Fm audio is present but like the Nt Mini this is close approximation of the original but still sounds different.

Despite having all 3 of those in my collection I still have a fm modded master system on my wishlist. It's just a large amount of money to get completely accurate fm audio. There are only a few games where the fm audio really shines.

American master system - no fm audio. Mod possible but requires soldering and a part sold by Tim Worthington (N64Rgb). If you install a switch you can do 3 options. turn off FM audio,turn on US FM audio, and turn on Japan FM audio. Real deal Yamaha chip.

Japanese Mk-2000 SMS - FM audio (real Yamaha ym2413), rapid fire support, and 3d glasses all built in. Master everdrive will likely need downgraded firmware and a cart adapter.

Sega mark iii with fm audio module - ancient and justified. Requires an rgb amp mod to provide a decent picture. Master everdrive requires a lower firmware, an internal mod on the sms, and an adapter. I don't think save states or in game menu work.


There are a few examples out there that compare fm audio across few of those options. Due to a lot of factors the audio seems to sounds a little different on each setup.

[Lawfer]

Master everdrive will likely need downgraded firmware and a cart adapter.

Master everdrive requires a lower firmware, an internal mod on the sms, and an adapter.

Why?

For info they recently released a new Everdrive a few months back, the Master Everdrive X7.

[Gara]

Master everdrive will likely need downgraded firmware and a cart adapter.

Master everdrive requires a lower firmware, an internal mod on the sms, and an adapter.

Why?

For info they recently released a new Everdrive a few months back, the Master Everdrive X7.

Was that finally resolved? There was some old issues and I couldn't tell if it was addressed in future versions as the change logs are not very detailed. The customer base for the master everdrive is really small so info is limited.

The only recent discussion I can find on the mk-2000 is a possible problem on the in game menu. It apparently has trouble working on some revisions.

[eric90000]

You can test it in different spots by using a pair of powered speakers and hooking some probes up to them.

Ideally you want an alligator clip on the negative speaker input and a probe on the positive input.

then you clamp the negative to a good ground on the motherboard.

Put a game in the master system and boot it. Get yourself a pinout of the relevant audio chips. then you can use the probe to listen to the audio outputs on the chips. If you hear nice clear sound, the chip is good. if you dont, its not.
Pin 9 on the CXA1145 should be your audio output.

So I made an audio test probe today. Do I need any passive components on the positive probe tip? I saw someone on YouTube make a test probe for a tube amplifier and put a 0.1uF 400V cap in to block DC to the speaker if you probe something dodgey. Would I need something like that with 9V/5V DC stuff e.g. Sega Master System?