Roland VGA-7

Started by Elantric, February 10, 2008, 09:10:22 PM

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admin

Its best to contact your local Roland Repair Center.

They have access to the VGA-7 Service Manual, and I have heard that some Roland Repair Centers do re-sell  Service Manuals to users. 

frankpaush

@admsustainiac excellent idea, I will try this!

Mo Tanner

#52
Hi all, been a long time since I was around.

I purchased a new VGA-7 amp chassis without the cab that I'm going to install in a head box.
The bloke who pulled it out of the broken in shipping cab paid no attention and so far I haven't been able
to find a schematic or good pic.

If a VGA-7 user would be kind enough to look in the back of their amp and tell me what colors go to which
speakers it would be greatly appreciated.

Thanks        Mo

dave_n_s

#53
I've bought a VGA-7 (actually my second having sold the first and succumbed again when this one was listed locally).

The previous owner had never used a 13 pin pickup, and I'd not got a 13 pin guitar available (with plans to buy a Godin, but not quite coordinated)

From the pinout, I learned 1 to 6 are the strings, so attempted to inject a 500Hz signal of a few hundred millivolts between one of the pins and ground. Nothing happened.

Is there a method for a basic function check of the 13 pin of the amp? The rest, from 1/4 in analog input works fine.

What was I missing?

I know Roland stuff is reliable, but the seller - a reasonable local guy - and I would like to know all is well.



Thanks


Elantric

#54
You really need a  GK 13 pin PU to get that amp running

Review the schematics thread
https://www.vguitarforums.com/smf/index.php?topic=73.0
There is only one Ground, the large round barrel on the DIN13 plug

Also no sound will occur without the GK volume Control Voltage (+5VDC) feeding pin #8

dave_n_s

Thank you. I was using the shield as return

That's what I had deduced, hoping the control voltage wasn't necessary for basic function, just the logic up / down & volume.


happyjay

frank:

I realize it's quite some time since your post, but I just stumbled on it. I'd be very interested in knowing if you scored a technical manual with schematics. A well known amp modder and builder is willing to put a stereo FX loop in mine if I can get hold of the schematics.

Muzition

If you read the owner's manual, you'll realize there's already a stereo effects loop built into the amp.

Muzition

Why not take it to store like Guitar Center and try out the amp with GK equipped guitar?  It's less painful than reverse engineering a cable.

VGA-7

Aloha everyone!
Mahalo for all the great info on this forum! A while back I won a VGA-7 head in an auction on
ebay for parts or repair,the winning bid was $20.95, shipping was $50.00.I hoped I would be able to reset or use my original VGA-7 to bulk dump into the head and restore it but I couldn't even get it in mode to accept a load.
I put it away and later noticed this post(  ..sorry for tearing the thread out of its grave ... I recently got a VGA-7 thrown away by its former user. because the whole digital section seems to be out of function. No lights, no reaction. The poweramp section is in function, using the EXT in a signal is coming out of the speakers, adjustable by Master volume. Easy way could be there is missing any power coming from the power amp board to the digital board. Unfortunately I can't find any instruction about the values that must be seen at the multiplug.)
I finally got around to checking and yes it's true the power amp still works ;D !
So now i should be able to use it to power my GP-10,among other things.
I just wanted to remind everyone that even if the preamp section is fried due to trying to update (it seems that was a common problem and there are probably lots of cheap to free heads around) .
Now I need to find out the spk wiring sequence,there are 2 blk (grnd probably)2 red,2 orange,and 2 brwn. Anyone got any Ideas? Thanks in advance and good luck finding deals!

Gibson L6S /gk2a , Bradley mini strat  /gk2a VGA-7 amp ,GR-33 , GP-10,SY1K, RMC breakout box, PK5 midi pedals,CM-64 sound module, Oberheim EDP  ,Boss RC-300,Digitech TRIO and TRIO +, Alesis DM5, GX2 Gear Shifter and GKPX-14

Vjammer

#60
Can anyone tell me how I can change the internal battery on my VGA 7? I really don't want to pay to have this done if I don't have to.

Gurbz

There's a vga-7 for sale in my neighbourhood. I'm using a vg-88 (guitar modeling, not amp modeling) and a katana head/2x12 marshall cab and I'm happy with that. Am I missing an opportunity here? Is the vga-7 a better sounding amp?
Grtz,

Gurbz

Frankenstein GK2-A strat/VG-88/GP-10/Cube 80XL/M-audio black box/Heritage guitars/Hook Amps/ Boss ME-5/Boss ME-8/Boss GT-3/Boss GT-5/Pro co RAT 1987/ Meris pedals/ Ton of eighties rack gear

admin

#62
Quote from: Gurbz on February 08, 2018, 10:15:09 PM
There's a vga-7 for sale in my neighbourhood. I'm using a vg-88 (guitar modeling, not amp modeling) and a katana head/2x12 marshall cab and I'm happy with that. Am I missing an opportunity here? Is the vga-7 a better sounding amp?
https://www.vguitarforums.com/smf/index.php?action=dlattach;topic=262.0;attach=11445
How strong is your back?

Weight 37.6 kG / 83lbs

Gurbz

 :)
Sound quality is the question
Grtz,

Gurbz

Frankenstein GK2-A strat/VG-88/GP-10/Cube 80XL/M-audio black box/Heritage guitars/Hook Amps/ Boss ME-5/Boss ME-8/Boss GT-3/Boss GT-5/Pro co RAT 1987/ Meris pedals/ Ton of eighties rack gear

Elantric

#64
Quote from: Gurbz on February 09, 2018, 02:56:26 AM
:)
Sound quality is the question

VGA-7 is Stereo 2 x 12" with separate HF tweeters

But its open back cab lacks low end for use with Synth patches

Its GK COSM processing is a step backward from the VG-88 IMHO.

And at 83 pounds the cab is heavy and bulky when  moving, and service manuals are unobtainium  , its pushing 20 years old  - they only made them 2000-2001, and expect electrolytic cap failure  / power supply failure.


start here and download all the VGA-7 docs on the bottom of 1st post
https://www.vguitarforums.com/smf/index.php?topic=262.0

Gurbz

Thanks, it is still for sale :)
Grtz,

Gurbz

Frankenstein GK2-A strat/VG-88/GP-10/Cube 80XL/M-audio black box/Heritage guitars/Hook Amps/ Boss ME-5/Boss ME-8/Boss GT-3/Boss GT-5/Pro co RAT 1987/ Meris pedals/ Ton of eighties rack gear


redstone

#67
Bricked Roland VGA-7.  I still use mine, the one I bought "new" a long time ago.  That is, I still used it until a few years ago, when I thought I'd upgrade the original firmware from 1.0 to 1.1. What could go wrong?  Of course the upgrade failed.  An occasional front panel light might come on when powered up, but otherwise it was bricked dead.  Roland USA was no help.  Roland Japan was no help. >:(.  So, I set to fixing it, on my own.

The short of this, I made a "new" copy of the Intel Flash chip based on the 1.1 upgrade bits that I managed to find on some site (UK, I think), removed the damaged chip and replaced it with my copy.  My VGA-7 is now back in business :).  (The attached picture shows the "damaged Flash" chip before replacement.)

If anyone still has a bricked VGA-7, and it's important enough to try to get it working again, maybe I can help.  As I invested a small fortune of $ and a huge amount of time in what I needed to do this, there's no way I'd ever come close to making my money back.  But, I will offer the few extra copies I have of this flash chip for a nominal fee to help out the few who still might care: $$ + shipping.

Changing a TSOP48 chip is not too bad, "if you know how".  If you don't know yourself, there's probably somebody close by who is qualified and has the tools.  The main board has to come out, change the chip, check each pin for continuity and no pin-to-pin shorting, re-assemble and you're done (if that's the only problem!!) But keep in mind, that I offer no guarantees and no refunds.  This worked for me, it might for you.

Elantric

#68
Wow - that is a great offer for those with a bricked VGA-7


FWIW - several folks acquired a VGA-7 without cabinet or speakers and were desperate for any info on the speaker connections

If you could post any pics of the VGA-7 Speaker connections , that might help many others

Mo Tanner wrote>
QuoteHi all, been a long time since I was around.

I purchased a new VGA-7 amp chassis without the cab that I'm going to install in a head box.
The bloke who pulled it out of the broken in shipping cab paid no attention and so far I haven't been able
to find a schematic or good pic.

If a VGA-7 user would be kind enough to look in the back of their amp and tell me what colors go to which
speakers it would be greatly appreciated.

Thanks        Mo




redstone

#69
VGA-7 speaker wiring:  Red/Black - right channel (stage right), Orange/Brown - left channel.  Large, spade lugs for woofers, small spade lugs for tweeters.  Original speakers terminals are marked or designated +/-:  red and orange connect to "+" terminals.

chazz

I went against my better financial and physical logic and bought the 80 pound plus VGA7 but got it for under $375 and 70 miles from home.
Generally they go for 500 or more and they are not local.
Now I have my guitar man toys of my dreams.
My three sons.
GODIN XTSA 3 VOICE
ROLAND VGA7
ROLAND GR55
I need a free roadie for the almost 100 pounds the 8th inch plywood and cover I will make for amp.
its a happy week
Now comes reality of being an old fat guy playing one of the best set ups on Earth and with no band or gigs.  IM HAPPY

plexified

I've been unable to find a schematic for this amp, and was wondering if anyone could point me in the right direction. For now , does this amp have  internal fuses?  I've seen these power transformers with several fuses before in other various SS circuits. Thanks in advance

admin

If you locate VGA-7 Service Notes - share

merman93

#73
I sold my original VGA-7 in 2010 for about $700. I just purchased one in perfect condition for $299 for use with my Kemper. The original 12's were replaced with Celestial coaxials, with switch to activate the stock tweeter/horns, or, a pot to "dial in" the tweeters on the Celestians.

The coax's feel better. and are much less directional than I remember my old VGA-7. If I moved a few feet either way, it lost the belief of it being a real guitar amp. I rarely use the original horns, and actually dial the coax tweeters down to about 70%.

This is much more economical that the FRFR cabs I see Kemper/Axe FX guys buying, and close to the same weight.
If I could excise the COSM/VG parts, and just keep the Aux in to power amp to save weight I would, as Thats all I ever use.

BTW, only the VGA-7 had the Tweeters. The VGA 3, and VGA 7 had gk inputs, but the VGA 5 didn't, which I always wondered about. 
Ibanez RG 1520 GK
Ibanez RG 420 GK
Ibanez RG 920 (GK KIT)
Ibanez RGA 121 (GK 3)
Fender Deluxe Players Strat (GK KIT)
Roland GC 1/G 505/G 707
Hamer Phantom A7 (24 pin)
BX 13 (24 -13 pin converter)
GP-10
FishmanTripleplay (2)
VG 88 2.0
Apple Imac/Logic 9
MOTU Utralite 3
Kemper (2)
Gemini 2 Active FRFR

carlb

Cool speaker mod, a guitarists take on something like FRFR.

Can you go into the circuit you used to dial in the tweeters? Or was it straight-forward: Decouple the Celestion tweeters, feed from the VGA-7 tweeter outputs?

How heavy is the VGA-7? Some of those VGA series were very weighty, if I remember.
ES Les Paul, internal Roland GK
Boss SY-1000, Valeton Coral Amp pedal
Morningstar MC8 & MC6
QSC CP8 powered speaker