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How could I get an extra bit of audio output from my MZ-R500?

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walkdude

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I was wondering if theres a way to get an extra bit of output from my MZ-R500 via Service mode? I want to play back louder, instead of recording a clippy mess to get extra output...

I would also like a bit more info on the service menus and such for the DSP...

You might want to start here. Looks like there's no (analog) "line out" possibility for this model.

However, there may be a hack you can do (or copy) if you read this thread. Note the last post I just added. This may give you optical or coax out, sounds like what you would need.

I don't think there's a headphone volume hack for setting the destination on this generation of machines, but you could look at the service manual in the equipment browser.

Stephen

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I was wondering if theres a way to get an extra bit of output from my MZ-R500 via Service mode? I want to play back louder, instead of recording a clippy mess to get extra output...

I would also like a bit more info on the service menus and such for the DSP...

Hi walkdude. The only way I can see is to remove, change or short out resistprs. You will need the service manual here:

http://minidisc.org/manuals/sony/service/sony_MZ-R500+R500PC_service_manual.pdf

Look at page 44. The DAC outputs are fed to the headphone amplifier IC302 via resistor dividers. Left channel is via R103, with R107 to 'ground' (actually a bias point from IC302, but you can regard it as analogue ground). For non-US models R112 is in parallel with R107, reducing its value slightly and thus reducing the maximum volume. The right channel is similar with resistors R203, R207 and R212.

To increase volume slightly you can just remove the resistors R112 and R212. Removal is going to be a darn sight easier than replacing or shorting out resistors, unless you are very experienced at soldering. You wait 'til you see the size of these components!

To increase volume even further you could try increasing the value of R107 and R207. The maximum increase in volume will be obtained by removing R107/207 entirely so that the input impedance of the amplifier is all that loads the signal down to ground.

Finding R107/207 and R112/212 is easy. They are on the underside of the main board, at the end of the line input jack socket. Refer to the circuit board layout on page 40. But if you damage your circuit board, please don't blame me.

I am just going to get an R500/501 out now to remove these components and see what difference it makes. I will report back.

Jim

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As I suspected, removing R112 and R212 makes an obvious difference to the overall volume. What you effectively get is the US model, without the volume limiting required for the European and other markets. I wouldn't suggest removing anything else but these two resistors - they are the two outer ones of the run of four. With these removed the volume is almost unbearable at maximum, with obvious distortion starting to be heard.

But, you are going to need a very good soldering iron, some solder braid, fine multicore solder and a steady hand. Even I found it difficult going, and I have been wielding soldering irons since I was ten years old (a long, long time ago)!

Jim

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With these removed the volume is almost unbearable at maximum, with obvious distortion starting to be heard.

Could this be because the capacitors marked with an asterisk need also to be changed? Moi, no idea, but I see the alteration in the diagram.

Pretty cool hackery, Jim!

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Could this be because the capacitors marked with an asterisk need also to be changed? Moi, no idea, but I see the alteration in the diagram.

Pretty cool hackery, Jim!

The distortion will probably be the output transistors in the audio IC clipping as they saturate to the power lines, or perhaps my earphones (which are only the cheap Sony jobs which came with the first ever portable radio I bought. Always used them, they just seem to fit my lugs now).

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