TechniX and MegaSound MX4 boards by ACME!

[TotO]

This hardware would be like the ZX Spectrum - Turbosound, maybe? 

Just looking about the Turbosound board. It is close, you are right.
Probably we can reuse the existing tools in that way, as the MegaSound allows more.

[TotO]

The first batch is finaly for 20 PCB (thanks the discount code). So, lets go! 

[LambdaMikel]

That's cool! Will existing trackers work easily with it?

Just found the MoonSound sound card for the MSX, which apparently was the best sound card ever made for the MSX - it seems it has on-board sample memory: 



Samples will have to be played from CPC bus with MegaSound though, right?

[TotO]

The MoonSound use a PC audio circuit that allows many things... May be too much for a 8-bit computer.
The MegaSound is not this kind of expansion, as it is more dedicated to speech and arcade games sound.

I will post some examples when I will receive the prototype board! 
(samples are played using the CPU to manage n channels, else it is not funny)

[LambdaMikel]

(samples are played using the CPU to manage n channels, else it is not funny)

... which puts a very high load on the poor little Z80 CPU (and mem requirements) though - LambdaDrum has 3 PCM channels which can be played from a BASIC program 


But it is good to give demo makers and coders a challenge 

[LambdaMikel]

The MoonSound use a PC audio circuit that allows many things... May be too much for a 8-bit computer.

This one

https://en.wikipedia.org/wiki/Yamaha_YMF278 

I guess this is why they had to do on-board PCM sample memory, because the Z80 would have been incapable of serving the device with a high quality PCM sample stream (and memory requirements for samples as well of course - well with 4 MB of RAM available on the normal CPC, that's no longer a problem, but I still fear that the Z80 would have to spend most of its time serving the PCM audio data stream with <n> channels).

[TotO]

Yes, the OPL4 circuit. And yes, the chip play itseft the samples, like an MP3 player in example.
About the CPU usage, it is what made a CPC fun to code and to use. Else, no challenge at all if it does nothing.

[LambdaMikel]

Yes, the OPL4 circuit. And yes, the chip play itseft the samples, like an MP3 player in example.
About the CPU usage, it is what made a CPC fun to code and to use. Else, no challenge at all if it does nothing.

Alright, let's see what coders can do then! Looking forward to it. I am a big fan of sound tracker software.

[LambdaMikel]

Btw, anybody knows what the max sample quality / bit rate you can do with the Z80 per PCM channel?


No DMA, assuming that ALL CPU cycles can go into fetching samples from RAM and putting them on databus (leaves no cycles for tracker program then obviously, hence it's a theoretical upper limit).


It seems to me that already Amdrum maxed that out quite a bit... (with 3 channels of 8 Bit PCM - but then, no memory for larger samples anyhow back then, which is no longer a problem nowadays as noted).

It would be a pitty if the sound hardware was so competent, yet there was no way for the CPC to actually take advantage of it (without a CPU upgrade  )

[TotO]

You don't have to use all the Z80 power to copy few bytes per scanline to achieve 8KHz or 16KHz channels.
On PLUS machine, the DMA usage is great because it allows to do samples through the AY soundchip on a stock system.

(first post updated)

[Scarlettkitten]

@TotO put me down for 1 Megasound board please

[LambdaMikel]

You don't have to use all the Z80 power to copy few bytes per scanline to achieve 8KHz or 16KHz channels.
On PLUS machine, the DMA usage is great because it allows to do samples through the AY soundchip on a stock system.

Well I know what DMA is and I said *without* DMA ... standard CPC."Not that hard" wasn't the question - I was more curious to learn about the "upper limit" in number of channels and sample rate you can achieve in that way     

This is more for my personal learning  - what is the best way of doing PCM sample playing on a stock CPC, and what rate can you achieve with the best method (WITHOUT DMA).

We know that Amdrum can do 8 kHz 8 Bit PCM at 3 channels... over an external DAC at the databus, and it seems that is pretty much the limit. Or? (Actually, it is only ONE channel... polyphony is achieved by mixing in software, so that doesn't count - real physical individual channels sound much better of course, Amdrum only offers one)

[TotO]

I was more curious to learn about the "upper limit" in number of channels and sample rate you can achieve in that way

OK. I think that 2ch 16kHz with pitch control is doable... Probably 4ch without.

[remax]

Add me for a megasound.

Envoyé de mon SM-G930F en utilisant Tapatalk

Have i been forgotten ? 


EDIT : Perhaps i am the missing 13... Bad luck ?

[TotO]

 

[LambdaMikel]

Have i been forgotten ? 

Dude... you bought LambdaSpeak... 
(just kidding of course!!!)

[TotO]

No luck ! 

[remax]

14 is my day of birth so perfect 

[Kris]

Hi Toto,


Please add me for a megasound
Thx

[TotO]

I have first ordered 5pcb for doing final tests. The production has started yesterday and I will receive them next week.
If all is OK as expected, I will ask you the payement to order 20pcs more to run the first batch for April.

[TotO]

Tests boards received. 

[LambdaMikel]

Good news!Btw, will it be compatible with the TechnoMusique software?

[TotO]

Good news!Btw, will it be compatible with the TechnoMusique software?

Sure, it will. The MEA8000 is on the same I/O port.

[kawickboy]

I'm ready for the news batch of megasound please.

[yannis_uno]

TotO,


put me down for a Megasound please


Thank you!