Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Yamaha DX7 Technical Analysis

ajxs.me

Post reply on HN
Print view View original

51–60 of 130 posts

Re: Yamaha DX7 Technical Analysis

#51

Post by jacquesm »

joeberon wrote: post #29
boondaburrah wrote: post #28

Earlier quoted context omitted.

I think I saw somewhere that you can actually tell the LFO is done in software because it actually slows down if you move the sliders a lot while the CPU tries to pay attention to too much at once.

Yeah it's a shame, on the other chips you can get amazingly air-y textures by setting the LFO to noise and then putting the frequency all the way up. See this video for example: https://youtu.be/_xL3qr-9-ZE

It sounds to me as though a firmware patch should be able to fix that to some extent. The main culprit here is the interrupt service routine, which while tight likely isn't immune to some code golfing.

Re: Yamaha DX7 Technical Analysis

#52

Post by cto_of_antifa »

joeberon wrote: post #25
jacobvosmaer wrote: post #22

Earlier quoted context omitted.

I'm not sure. Intuitively I would think "phase angle" means "offset into the sine wave lookup table". If you step through the lookup table with constant size steps, you would get a sine wave. If the steps are not constant size then you get a distorted sine wave. The "rate of change of the phase angle" would then be the step size.

"frequency" would mean the same thing in your weird practical analogy.

Be polite, please.

Re: Yamaha DX7 Technical Analysis

#53

Post by boondaburrah »

joeberon wrote: post #29
boondaburrah wrote: post #28

Earlier quoted context omitted.

I think I saw somewhere that you can actually tell the LFO is done in software because it actually slows down if you move the sliders a lot while the CPU tries to pay attention to too much at once.

Yeah it's a shame, on the other chips you can get amazingly air-y textures by setting the LFO to noise and then putting the frequency all the way up. See this video for example: https://youtu.be/_xL3qr-9-ZE

Would sacrificing an operator and setting it to constant mode instead of mult work for this? You'd have to use the feedback operator if you wanted something noisy though.

Re: Yamaha DX7 Technical Analysis

#54

Post by boondaburrah »

jacquesm wrote: post #5
danbmil99 wrote: post #2

Awesome -- the DX7 had a huge musical impact.

I repair them to keep them in play, impossible to get some of the parts so I tend to use one that is too far gone to repair a number (usually three or so) of others and then I still end up with some more spares that might come in handy later. They are incredibly durable, one that I got had been in a fire but it still worked, even though more than half of the keyboard had been burned off. The mainboard went on to repa…

The DX7ii I have is a fucking tank of a machine and I'm playing it until it breaks, fixing it, and then playing it some more. I guess I kind of understand typical "car guys" now.

The best part is being able to map the sliders to /almost/ any parameter within a patch, so it's possible to have expressive control over the tonality of your instrument while playing live. Sure it involves menu diving to figure out ahead of time, but I'm a programmer. It's really more about the joy of being like "this sound needs more wonk, lets tie this parameter to the output of this other function and ooOOOH not what I was expecting but let's go"

Re: Yamaha DX7 Technical Analysis

#58

Post by jacquesm »

boondaburrah wrote: post #54
jacquesm wrote: post #5

Earlier quoted context omitted.

I repair them to keep them in play, impossible to get some of the parts so I tend to use one that is too far gone to repair a number (usually three or so) of others and then I still end up with some more spares that might come in handy later. They are incredibly durable, one that I got had been in a fire but it still worked, even though more than half of the keyboard had been burned off. The mainboard went on to repa…

The DX7ii I have is a fucking tank of a machine and I'm playing it until it breaks, fixing it, and then playing it some more. I guess I kind of understand typical "car guys" now. The best part is being able to map the sliders to /almost/ any parameter within a patch, so it's possible to have expressive control over the tonality of your instrument while playing live. Sure it involves menu diving to figure out ahead of…

Hah! You're using it like it was intended to be used, the DX-7 is first and foremost a performing musician's tool, that's exactly why it was built as strong as it was, made to be tossed in the back of the car on the way to gigs.

If you ever can't find a part let me know.

Re: Yamaha DX7 Technical Analysis

#59

Post by nkozyra »

jacquesm wrote: post #5
danbmil99 wrote: post #2

Awesome -- the DX7 had a huge musical impact.

I repair them to keep them in play, impossible to get some of the parts so I tend to use one that is too far gone to repair a number (usually three or so) of others and then I still end up with some more spares that might come in handy later. They are incredibly durable, one that I got had been in a fire but it still worked, even though more than half of the keyboard had been burned off. The mainboard went on to repa…

In the 90s, when FM was considered inherently uncool, the DX7 was the keyboard du jour to use as a controller and subsequently smash to pieces in live sets for industrial, ebm, techno.

They were dirt cheap and as mentioned, insanely solid.

Same thing happened to to the Casio CZ line. I bought one at a time they were very undesirable for $75 and they now go for $500+

There's a financial lesson in here somewhere

Re: Yamaha DX7 Technical Analysis

#60

Post by l33tbro »

jacquesm wrote: post #50
l33tbro wrote: post #13

Earlier quoted context omitted.

You don't happen to have a hi-hat decay slider for an MPC60 lying around? Can't find a replacement for the life of me, and I've taken to sad attempts like this when the opportunity arises :D

The cap? Or the actual slider? If you have the specs of the slider I can dig around for a suitable substitute, alternatively I can go on the lookout for a donor synth.

Will email you picture ;)
Post reply on HN