Roland GR33B afvice

[Burns-bass]

Hi all, I was lucky enough to get this package today. The bass is exceptional as you’d expect from an Ibanez build.
 

The sound from the synth pickup and synth unit is both intermittent and crackly. Volume changes up and down randomly. (I knew this issue before paying for the package and it was all priced in!)

 

I wanted to know if anyone could recommend a synth repair specialist or someone who could help me get it back to working order?

 

All comments and advice appreciated.

 

 

 

 

[itu]

That's one pretty old unit. I suppose cleaning all pots would be helpful. Do NOT use whichever liquid.

[Burns-bass]

4 minutes ago, itu said:

That's one pretty old unit. I suppose cleaning all pots would be helpful. Do NOT use whichever liquid.

Yeah it’s from 1982. I basically got the bass and the unit and cable were free.

[tauzero]

There's some info here: https://www.joness.com/gr300/GR-33B.htm

 

It would be an idea to check out the workings of the hex pickup and bass internals with a known good synth unit (GR20, GR55, GR-Bass, GR99) so you can determine if the issues are confined to the GR-33B.

[Burns-bass]

2 hours ago, tauzero said:

There's some info here: https://www.joness.com/gr300/GR-33B.htm

 

It would be an idea to check out the workings of the hex pickup and bass internals with a known good synth unit (GR20, GR55, GR-Bass, GR99) so you can determine if the issues are confined to the GR-33B.

This is excellent advice. The only thing is that it’s a 24 pin adapter and I think the newer units take a 13 pin.

 

I really need someone who knows the units to take a look as it’s just not something I have the experience to touch.

 

[NancyJohnson]

One thing I'd watch for is that when you're trying to hit a D, you'll get an F.

 

😀

[Burns-bass]

9 hours ago, NancyJohnson said:

One thing I'd watch for is that when you're trying to hit a D, you'll get an F.

 

😀

I see what you did there!

[BigRedX]

Does the direct jack from the bass into an amp work OK, and do all the associated controls on the bass that should should work in this mode function as expected without noise and crackles?

 

If so the next thing I would do is to get your multi-meter out and check every contact on the multiway cable ideally while flexing it to make sure there are no intermittent faults.

 

If both of those check out OK you'll need to get an analogue synth specialist to check the floor unit and the synth control on the bass. Go and ask on the Sound On Sound forums as there are people on there with the relevant info. Expect anyone good to be expensive and busy so it may be some time before they can get around to fixing it.

 

I'd also suggest that if you intend to use the synth part live that you invest in a spare good quality multi-way cable.

[Burns-bass]

45 minutes ago, BigRedX said:

Does the direct jack from the bass into an amp work OK, and do all the associated controls on the bass that should should work in this mode function as expected without noise and crackles?

 

If so the next thing I would do is to get your multi-meter out and check every contact on the multiway cable ideally while flexing it to make sure there are no intermittent faults.

 

If both of those check out OK you'll need to get an analogue synth specialist to check the floor unit and the synth control on the bass. Go and ask on the Sound On Sound forums as there are people on there with the relevant info. Expect anyone good to be expensive and busy so it may be some time before they can get around to fixing it.

 

I'd also suggest that if you intend to use the synth part live that you invest in a spare good quality multi-way cable.

Brilliant advice. The bass works perfectly as a standard bass. I do wonder if it’s the cable but they’re £100 to replace, so I’ll see.

 

When I raised the digital pickup height it improves the connection (but the signal is still intermittent).

 

Ive had some recommendations of experts and there’s a diagnostic cost and a fix cost. It is what it is.

 

I don’t want to use it live and happy to invest some cash in getting it fixed. Always makes me laugh when people complain about the cost of a musical instrument expert but won’t balk at paying an electrician £80 an hour…

As I said, the seller acknowledged all the issues (he nearly out the synth unit in the bin!) so I was essentially given it for free, so spending cash fixing it is no problem. 

 

[BigRedX]

The manual should include instructions for setting up the synth pickup and associated parameters to get the best response and tracking. 

 

One thing that strikes me is that the synth pickup is much further from the bridge than would normally be recommended which I find very strange as Roland's advice for their pickup system, when sold separately, was always to fit it as close to the saddles as was physically possible.

 

It might also be worth fitting a new set of strings.

[Burns-bass]

6 minutes ago, BigRedX said:

The manual should include instructions for setting up the synth pickup and associated parameters to get the best response and tracking. 

 

One thing that strikes me is that the synth pickup is much further from the bridge than would normally be recommended which I find very strange as Roland's advice for their pickup system, when sold separately, was always to fit it as close to the saddles as was physically possible.

 

It might also be worth fitting a new set of strings.

 

Thanks for the advice. Really appreciate you taking the time. I've got some time set aside to do a bit of a set up on it. It doesn't really need much, just a tweak of the truss rod and it should be fine. The frets are almost like new, it's a lovely instrument and I'm really pleased with it. 

[uk_lefty]

There's a synth repair person in Hemel Hempstead, Plasma music. I've used him to service my bass amps recently but his specialty is vintage synths. Might be worth a try if you can't resolve on your own 

[Burns-bass]

1 hour ago, uk_lefty said:

There's a synth repair person in Hemel Hempstead, Plasma music. I've used him to service my bass amps recently but his specialty is vintage synths. Might be worth a try if you can't resolve on your own 

There’s no chance I’ll be able to do it. Thanks for the link. I’ll drop them a message!

[ped]

Brilliant, what a find! I have found the https://www.vguitarforums.com/smf/index.php really helpful, some of the knowledgeable folk on there will be able to help I'm sure.

[police squad]

This is the bass that Phil Lynott used, much later in his career. Although he painted it black and put a mirror guard on it

[LukeFRC]

13 hours ago, BigRedX said:

 

If so the next thing I would do is to get your multi-meter out and check every contact on the multiway cable ideally while flexing it to make sure there are no intermittent faults.

Like bigredx suggests do this next. 
the faults you describe could be a damaged cable, and a cable is far more likely to get damaged over time than the inside of an effect unit … 

[Burns-bass]

17 hours ago, police squad said:

This is the bass that Phil Lynott used, much later in his career. Although he painted it black and put a mirror guard on it

That’s wonderful to know. Might take the bad boy to Chinatown later (love that song)

[Burns-bass]

OK, so I used some switch cleaner on everything and it's now producing a sound. The one issues I can see is that there's a switch that feels weak. It alternates between the signals (guitar - guitar/synth - synth). Do you think if this switch was faulty it could be causing the cutting in / cutting-out stuff?

 

The unit itself appears to function perfectly well, so I can't see that's a problem. 

[bloke_zero]

Oh cool! I had a good go with a GR-300 that a friend loaned me (the guitar version of this).

 

It's fundamentally different from later guitar synths as it derives the pitch directly from the pickup output, so it doesn't 'track' the pitch and then play something, it automatically generates a 'synth' sound from the input and you can then vary the pitch and pass through a filter. On the guitar version the tracking was instant and flawless, through it sounds like the bass version had some issues with tracking the open E & A? (https://www.joness.com/gr300/GR-33B.htm)

 

You have a really interesting and unique instrument there!

 

I'd say that if the sound is intermittent then it's very likely the switch as the synth portion pretty much just works as it's derived from the pickup output  (though as noted the pitch tracking might be a bit off on the open notes). I do know a guy that works on vintage synths if you identify issues with the synth part.

[BigRedX]

1 hour ago, bloke_zero said:

Oh cool! I had a good go with a GR-300 that a friend loaned me (the guitar version of this).

 

It's fundamentally different from later guitar synths as it derives the pitch directly from the pickup output, so it doesn't 'track' the pitch and then play something, it automatically generates a 'synth' sound from the input and you can then vary the pitch and pass through a filter. On the guitar version the tracking was instant and flawless, through it sounds like the bass version had some issues with tracking the open E & A? (https://www.joness.com/gr300/GR-33B.htm)

 

You have a really interesting and unique instrument there!

 

I'd say that if the sound is intermittent then it's very likely the switch as the synth portion pretty much just works as it's derived from the pickup output  (though as noted the pitch tracking might be a bit off on the open notes). I do know a guy that works on vintage synths if you identify issues with the synth part.

 

The GR300 is much more modern and IMO the way forward.

 

Deriving the oscillator frequency from the pitch of a plucked string is IMO a complete non-starter for bass guitars. The very best systems require ultra-clean, non-aggressive playing technique and a minimum of one and a half wave cycles to be able to detected the pitch of the string. That means under ideal circumstances the synth note is going to be 15ms late for open G and 36ms late for open E. 15ms is noticeable latency for most people and 36ms is very definitely in slap-back delay territory. Most of the time pitch detection will take longer.

[bloke_zero]

 

2 hours ago, BigRedX said:

 

The GR300 is much more modern and IMO the way forward.

Are we talking about the same thing? Both the GR-300 and GR33b are early 80's?

 

This is pretty interesting - 

https://www.premierguitar.com/side-by-side-roland-vb-99-and-gr-33b-bass-synthesizers

[itu]

Art of Noise (?) bassist commented once on synth bass something like he had to play ahead of the beat. Otherwise the sound was too late. After a tour he found out he had to learn to play on beat with an ordinary bass.

 

To shorten the lag, you should at least try piccolo strings on that bass. An old trick but certainly worth a try.