Yamaha DX7 repair - worth it?

madfresh

madfresh

New member
Hey, what's going on?

I have a Yamaha DX7 which I bought in 2007. I've had two problems with it: first, it started to sound weird around 1 year ago - the tone wound bend strangely in the attack of each note on every sound. Now, since last week the synth doesn't start up. I'm using a transformer as I bought it from the US and I'm living in the UK but the transformer works with my girlfriends hair straightener:) so the problem seems to be coming from the synth.

I want to get your opinion on whether it's worth repairing this synth or not. I'm sure some of you have experience with this model and can share some good advice. I've called a company which repairs vintage synths and they charge £65/hour and claimed that it would take around 1-2 hours to fix the synth. However, they said this over the phone so who knows, it might take longer than that.

What do you guys think?

(Btw, I'm living in London if anyone knows any places offering cheap repairs.)

//Aron
 
DX7's have a battery inside and when it goes out the thing goes beserk and the sounds get all screwed up. If the thing is working to some degree you can access the battery voltage in a certain screen. You need to load the voices back in after battery replacement, and you can get batteries and voices cheap on eBay.

Those things are classics now, and even if you don't fix it somebody else probably will. They are built like tanks and we only ever heard 1% of what they were capable of. The complexity of programming sounds on them is past most people.

Did it ever work with the transformer?

It's hard to say if it's worth fixing for you. I'd do it myself but I don't know if I'd want to pay someone else to do it. :( There's a risk involved in that the first thing I'd want to do would be to replace the battery and when you do that there's no guarantee that will fix it.

But yes, ultimately it should be fixed because they are too good to die.

They are still not a bad controller for a studio and most keyboard players agree that it was one of the best feeling plastic synth keyboards to play.
 
dintymoore

The synth worked for like a year before it started to sound funny.
I just called Yamaha's service department and they charge £40/hour. They said it might take more than one hour though considering there's several problems with it. They also said that the cause of the starting up problem could be the power cable...

Anyway, I'm gonna look into changing the battery myself. I suck at this kind of stuff but I know some people who could help out.

arcaxis

Thanks for those links. Gonna check them out!
 
Ditto that's it hard to say if the battery is the right one or not.

A couple of years ago I got some replacement DX7 batteries from oaktreevillage.com phone 719-964-7205.
 
Thanks guys. Unfortunately, Mouser doesn't ship that battery to the UK.
I will check out oaktrevillage.com.

Cheers!
 
madfresh said:
Thanks guys. Unfortunately, Mouser doesn't ship that battery to the UK.
I will check out oaktrevillage.com.

Cheers!
Click to expand...

Maybe try and see if anybody on eBay has it, that's where I found mine. The same battery is used in several Yamaha products, I had to put one in a DMP11 mixer.
 
All the DX7 cares about is that it receives 2.2-3V for memory backup, and while that's normally done with a 3V lithium coin-shaped battery (CR2032) soldered to the motherboard, you can unsolder that and replace it with an ordinary AA size two-battery holder. That gives you 3V.

To check the status of your battery you simply have to press "function" then "14" (battery check) and it will display on the LCD the voltage. It should be 2.2 to 3.0V.

Put in Energizer or Duracell alkaline batteries because they have the longest shelf life - about 6-7 years. Since the drain on the batteries is barely measurable, those batteries will last just about the length of their shelf life.

Use double-sided tape to attach the new battery holder into some empty space found inside the machine.

Now, when the batteries die in 6-7 years, you can just pop the machine apart, pull out a set of AA batteries out of the drawer, pop 'em in, and screw the thing back together and you're up and running again. Far better than mail ordering odd-ball parts and unsoldering the old one and soldering the new one in again.

I've done this to just about all of my equipment - digital mixers, hard disk recorders, samplers, synth modules, outboards, drum machines, and so on.

---

Regarding the "pitch bend with attack" issue, before you spend a dime I would do a full system reset - and I don't recall that the DX7 (the original) has that capability. If it does, it would be in the diagnostics menu on the LCD.

However, removing the internal battery for an hour or two will do the trick, so if you're going to replace the internal battery, just take your time to give the DX7 a chance to become "stupid" and lose all it's settings. Then put in the new battery - original style (CD2032 with leads or my AA holder idea above) and reload your patches through MIDI sysex or through a cartridge.
 
noisewreck said:
I'd get Native Instruments FM8. Much easier to program :D

I'll duck now :)
Click to expand...

I would only do that if they have some pia virtual battery you need to replace (takes hours and is awkward as hell) and virtual keys that break. Without that it just wouldn't be the same. :o

For me there's still a huge difference in sound quality between virtual instruments and the real deals.

I have a pair of Oberheim Matrix 1000's, and the virtual instruments I've heard... I'd compare it to porno vs a real girl.
 
frederic

Thanks for the advice, what you suggest sounds a bit less complicated. I really suck at this kind of stuff so I'm just wondering how do I connect the battery holder to the synth?
 
madfresh said:
frederic

Thanks for the advice, what you suggest sounds a bit less complicated. I really suck at this kind of stuff so I'm just wondering how do I connect the battery holder to the synth?
Click to expand...

You have to unsolder the original battery and solder in either a new battery, or the two leads from a two-AA battery holder.

The reason why I went with the AA holder is someday, *when* the batteries die, I can find a pair of AA batteries in my junk drawer, but if not, I can drive to any store and buy 'em. Coin-shaped batteries as you have discovered, are a pain in the butt to buy because you have to cross reference them then place and order, and wait impatiently for them to arrive.

Whether you repair the DX7 to factory specs or do my AA battery method, either way you have to solder. It's not difficult to do, but you might want to practice soldering on something else and not your prized keyboard if you're new to soldering.
 
noisewreck said:
I'd get Native Instruments FM8. Much easier to program :D

I'll duck now :)
Click to expand...

I was going to suggest that

dintymoore said:
I would only do that if they have some pia virtual battery you need to replace (takes hours and is awkward as hell) and virtual keys that break. Without that it just wouldn't be the same. :o

For me there's still a huge difference in sound quality between virtual instruments and the real deals.
Click to expand...

not with this one dinty..i know what you are saying but other than the DX7s grit Id say FM8 actually sounds better overall.....the software has surpassed the original in this case...

imho of course ;)
 
Ok. I've never soldered anything before but I've heard it's supposed to be exciting. No but my land lord is mean with handy stuff and I think he can help me out. As a thank you I can finally pay the rent on time.

Thanks for the info. Hopefully I can manage to make the synth work again!
 
I had a DX-7 since new in 1983. A few years ago it just went.

The chips go. Easier to buy a replacement than fix, at a certain point.
On mine, the sliders went first (disintegrated) then the chips started to go.

Now it is scrap - gave to local repair shop for any parts they could salvage.

This happens with any synth or keyboard: over time they go.
Chips are the worst - - some can't be rebuilt.

So ... I tend to buy at low price, sell when prices reaches zenith.
Get the hell out and buy something newer.

Unless you have a warehouse and technical person working for you full time, the old synths are a handful. I used to own one of everything: Moogs, ARPs, Oberheims, CS-80's, the lot.

Now I own simpler, newer stuff (nothing over 15 years old).
Twenty years seems about the limit for electronic equipment.

Your local craigslist is full of dying junk . . at high prices.
I've gone to look at broken Polymoogs that were still selling for $4,000.

Just junk. Buy a new computer and some plugins.
 
Unless madfresh has ruled out the battery I'd say that it's bad advice to throw away a classic synth because it needed a $3 battery and 45 min soldering time.

At the same time I've seen people throw away perfectly good cars that only need a new battery. :(
 
I've got a dead Jun0 106, a Sequential Circuits Six-trak, and a JX3p if any of you bleeding hearts want to fix them. I ain't dropping 75 bucks per bench fees so that I can be told "they don't make that ic anymore".

So my vote on the DX7 is a resounding No.

Also, fuck FM piano sounds. :vomit:
 
Myself for $3 if the battery fixed it you could probably sell it for $100... should take about an hour... not a bad gig.

Supercreep I have a working and a parts Six-Trak, that was my first sequencing DAW in 1983. They still have a great Moog type bass. Great keyboard, you might be able to sell it for parts. Wine Country still services (and buys) Sequentials. http://www.winecountrysequential.com/

It's funny, when you write MIDI Sys Ex code, one of the first things is the manufacturer's ID, it's a number assigned to each company, and Sequential Circuits number is "01". That's because it's owner David Smith pretty much wrote the MIDI code.

In 1984 I had a meeting with John Bowen and we drove everyone so nuts that they all left and we talked for hours about MIDI. John programmed the sounds in the 6-Trak and later did the Korg Wavestation. He was the first Moog clinician in 1973! Another example of how when you meet the real guys at the top that they are regular nice people.
 
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I've been away on vacation so haven't been able to fix this thing but I'm back no so gonna buy an AA battery holder, some batteries and sweet talk my land lord into helping me out with the soldering out. I'll let you guys know how it went.

Btw, this is my motivation for getting the synth fixed:

Harajyuku Sisters - "DX7 is FUNK"
 
Thanks for that, arcaxis. Actually, I had my landlord remove the old battery and replace it with battery holder and two AAs. Unfortunately, the synth would still not turn on. Does anyone have any ideas on what else could be the problem?
 
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