Well, needs more power (1 amp more than RPi4) - is this inside of the spec of the onboard regulator?
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Yes. No problem with it. V5 main board power source is perfectly capable.
Regarding the heat dissipation, i’m not really worried about it. The Pi5 is more efficient than the Pi4, so it will generate less heat for the same amount of load. When zynthian is really busy, the thermal block should be capable of managing 5 extra watts. When this happens, if the ambient is hot, the alucase can get really hot (although probably not so hot to cause the Pi to throtle). In such a case, an external fan should be the best solution to keep the case at a lower temperature.
Regards
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And I can vouch for the efficacy of the zynthian-pwm-fan module…
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Could you explain-expand that? Perhaps a pointer if required…
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Ahhh, thank you, very interesting indeed, and the correction of the Motorola number also made a search of this forum pop up: Access Virus emulator on Zynthian?
So I can see what I think is the point - the increased performance of RPi5 might allow this DSP56300 to run on Zynthian, and of course @jofemodo 's work on Bookworm-64bit might yield enough performance as well. With both - Wow!
I’ll have a look at what my Alesis Micron-Ion are running, I remember it was some kind of Motorola-NXP Coldfire processor. I would certainly like to have those in Zynthian.
The Alesis Ion and Micron (and Akai Miniak) all use the same Alesis-designed AL3101 DSP chip, one per voice. (See for instance MATRIXSYNTH: Inside the Alesis Micron). The Coldfire seems to be used as a control processor.
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Oh, very interesting. It did seem incredible that they got all that sound from what was basically a souped up 68000! Although it does have some sort of DSP enhancement(s), like a ‘Multiply and Add’ instruction. I wonder if it even used any of them. Thanks for the pointer.
The RPi5 does not have 3.5mm audio jack so we would lose the ability to build a Zynthian with no extra hardware. This is something that we suggest to nervous investors… those who want to see how wonderful Zynthian is without the commitment. It’s also the output we planned to use for accessibility enhancement so we would need to rethink some of this.
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True, but I think we, as in royal ‘we’, might be able to substitute the ability to route output via Bluetooth to a speaker or earbuds. I think most people have some kind of ability to listen via a Bluetooth device.
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Amazing. I find very fascinating the concept of emulating a slower purpose-built processor within the instructions of a faster general-purpose CPU.
There must have been quite a lot of reverse-engineering in devising/guessing which specific ROM-level signal processing routines have been used by Access, in their specific implementation of the DSP kernel macros available for the chosen Motorola processor.
The programming aesthetics in reproducing DSP nuclei as adaptive real-time bits of code and related CPU processes is very elegant. 
It’s easy enough to plug in a USB sound card for a tryout as well though. I think as long as you keep compatibility with generic USB devices, it’ll end up being a better experience for tire kickers, cause as we all know, that jack was not good sound.
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We do lose the audio jack in this revision. Not end of the world, but it has been useful for headphones + line out.
Am I wrong or was the buildin audio jack 12bit PWM only? Hmmm…, sorry, but IMHO this is only useful for testing.
Exactly. It also works “good enough” as a headphone monitor I guess.
The original implementation of the onboard sound was truly terrible. There was an improvement a few years ago which made it not too bad. It certainly isn’t audiophile quality but it is a really useful output for beginners and toe-tippers to use. It allows someone to build a Zynthian without any external hardware which is a great option for testing whether this is something worth investing in. These people may not have a USB soundcard lying around.
We also use the onboard sound as the headphone feed on older models and some users may wish to continue to do so.
We have also been working on accessibility options that output audio description via this output to be mixed with the main output to a headphone feed.
So this will be a loss but we can find ways to work around most of that.
Note that using the onboard sound is a bad idea generally, not just because of its limited audio quality but also because it is bit-banged and consumes quite a bit of CPU which can lead to xruns. (This is why I don’t like using it as a headphone output where the problem is compounded by the need to samplerate convert to sync the audio clocks.)
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The new RP1 chipset is the more exciting piece in this RBPi5 imo.
The Gpios header pins aren’t directly connected To CPU anymore but are now "programmable " through RP1 chipset.
So I wonder if more I2S data lanes are possible ?
Looking forward to the zynthian 255 channel mixing desk synth in that case!
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No:
255+0=256=2⁸
this is too much for me. I’m not like Berlioz, which has involved a double symphonic orchestra or a triple choir in his compositions (with eventually, the famous octobass).
No. But having a different mix for the headphones and for the main output is for me a must have in my use case of the Zyn