On Sep 17, 2017, at 1:13,?grantbt@...?[YamahaDX] <YamahaDX@...> wrote:

Thank you for posting this. As Daniel has mentioned there is perhaps a large amount of pent up demand for something like this. Is there no issue with using the PCB traces as contacts? I know this has been done in the 80's and 90's but it seems all the recent attempts (even here on this group) have failed to achieve popular success because of board thickness or some other issue making them unreliable. I hope yours does work.??

?

Hi Daniel & grant, thank you for your answer !

I suspected someone did it before, but didn't look further...Actually, I have a bunch of 27C801 in the bottom of a drawer and wondered what to do with them ;-)....

@Daniel
For now, I only ordered the regular 3 pieces batch from OSH; there's one unpopulated card left, the two others acted as prototypes...The total amount for that batch was 45€, so a card price is 15€. Including EPROM, all the components and shipping costs, I guess a total amount of ~30€...
There's no problem for me to burn your own SYSEX : you've just to send me the list of the patches you want to be included in the EPROM ;-)...

I don't plan to design cards for other machines, as long as I don't own them ;-)...Maybe later, I'll cogit about an Arduino/SD Card interface for my DX7...

@grant
Yes, I noticed the existence of cards using PCB traces for contact...the thickness of the PCB sold by OSH seem to be satisfactory, I didn't encounter problems of bad contact...Of course, it's necessary to see in duration after many insertions/extractions....I can't tell, it works perfectly for now !

Of course I would be glad to make the board available on OSH; I'll see how it works.

Chris.

On Sep 16, 2017, at 23:14, christophe.perrod@... [YamahaDX] <YamahaDX@...> wrote:

[Attachment(s)?from?christophe.perrod@...?[YamahaDX] included below]?

Hi everybody,

I was fed up to boot the computer each time I wanted to try a new SYSEX...so I designed a ROM card for the DX7 built around a 27C801 EPROM ( 1MB ) and ended up with a perfectly working device able to store 256 x 32 = 4096 patches...whereof to stay awake late in the night before needing to erase and burn the EPROM again....

There's no mystery in my design, based upon the original ROM card circuitry supplied by Yamaha, which I extended the adressing bus with 8 additional lines controlled by DIP switches for highest adress bits, allowing selection of one of the 256 banks.
I had to write a ( rough for now ) Python script to extract datas from SYSEXes ( basically to remove the MIDI-dedicated bytes ) and to build the .bin file to be sent to the EPROM programmer. For now, I filled the ROM to the brim with 256 SYSEXes picked up at random ;-)

As said, the prototype seems to work very well ( though I didn't test every single patch....)

If someone is interested in such a device, I can launch a batch at OSH Park for PCBs and send them once I've received them. I can also supply rightly programmed 27C801 EPROM, or even a complete kit with all the components ( a few indeed ). Let me know !

I attach to this message pictures of the card and the script I used ( in French, sorry....).

Chris.

On Sep 16, 2017, at 12:56,?teovincent4@...?[YamahaDX] <YamahaDX@...> wrote:

[Attachment(s)?from?teovincent4@...?[YamahaDX] included below]?

Hi Andy and groupies! :)

At the risk of being picked on for something, giving away ideas? Showing off? watevah..

I'll attach those 2 files, I don't think as good as uploading into the files section, maybe I can upload them to files IN STEALTH MODE so I don't get picked on?

I mean, if I felt safe doing it, I would upload the score files from IMSLP, look, we are collectively getting more intelligent with technology right?

Man there are some grace notes I REALLY need to talk to flamenco guitarists and knowledgeable Scarlatti people about, the F Minor sonata I uploaded parts of befor I think the grace notes should be BEFORE the beat which is supposedly against all rules of baroque, but I know my guitarist buddies would say it's smoother that way, and who knows, Scarlatti stayed in Spain the rest of his life, 2nd wife was Spanish, maybe he was ahead of his time with the grace notes and I'd be glad to share my research on that.. maybe find a Baroque Ornaments group or if people would like to learn something I'll share the techniques here because the harpsichord is more like a guitar anyway, and it is all about tasteful interpretations anyway!

Back to the point. These samples have K. 1, his first Sonata in D Minor and well, the last note should technically start above the note so B-A-B-A but I just do A-B-A again interpretation thoughts..

For your left-right speaker issue Andy I'll apply the Amadeus-Apple-Matrix-Reverb effect like I did before but try and make it less "in-the-way" and thanks for that comment before :)

The real test here is how the high parts go wacko, I usually play whatever I've recorded in every computer / stereo / car I can, and I feel the High-Harpsi or whatever the built in sound is called is OK generally but poor at the high register - the 2 keyboards really differ that way, I find Low-Harpsi sounds OK high! Go figure?!?

Funny I was saying to myself the right keyboard was too quiet then opened up my control panel and the pan was set slightly to the left, fixed it and they were great volumes together. I LIKE the pure left against pure right, anyone else agree? (I hope so, I'll call it confirmation and keep it up!)

The 3rd, Scarlatti K. 208 is on it's way to done, nothing too high or low, I didn't do the A&B parts dry like I will when the final recording is done. In a sense I'm letting myself hear what my fakest of harpsichords sounds like to think of how to describe it! Also I've only recorded 1 Scarlatti so far - on piano - I'll do that on Freeboards (2 DX100s) some time. I love Scarlatti's formula-like endings, always different but sort of perfect! Theory-wise.

Tonight I tried my tired old Safari browser first and I couldn't get the files either, but that Safari can't secure-connect to things all the time, like I said, maybe I'll upload them here in a sub-sub-sub folder and no one will mind?

Thanks for your time and sorry for the long-windedness, hey, when you FINALLY find a person or 3 that might have some slight interest in your secret whim development project you want to share, kapitsch? Forgive me.

Teo