Reverb humm ---Roland Jazz Chorus

Jeff

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The reverb on my Roland has developed a noticeable hum. Bummer man, I forgot about it till I dug my T 5 out to practice some blues & jazz bits I've attempted to learn lately. Even without the reverb it's been some fun, The T 5 is no X 500 but it'll do till I can save up for a real Jazz guitar. [img:450:337]http://www.imagestation.com/picture/sraid220/p273bcd2891f9383692d82a4147291467/ebd58c35.jpg[/img]





[img:450:337]http://www.imagestation.com/picture/sraid220/p69615bb401f7b0631460e2b25056fa29/ebd58d4e.jpg[/img] Can anyone tell me how to test the amp to make sure the problem is the amp & not some peripheral(sp) issue.

The hum disappears when the reverb is turned to zero & increases as the reverb is boosted. Doesn't matter if a guitar is plugged in or not, lots of static accompanied by a mid range hum .
 

capnjuan

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Potz first:

Get some De-Oxit or comparable spray-on cleaner and clean the pots. Open the chassis and spray liberally on the reverb pot and every other one. Turn them back and forth several times.

Use the type that lubricates; the pot shafts have a doink of grease on them to keep them turning; if you use the non-lubricating type, you can 'wash out' the shaft lube.

If your reverb, or any other pot, has a stiffish, sort of greasy feel to it, cleaners will usually help. The 'right' condition is a slight sense of drag as the wiper moves across the resistive element; you should almost be able to feel a little vibration as you turn it slowly.

Other points of contact:

While you're at it and the amp is unplugged (do not put finger in your ear), spray some cleaner on the on/off switch and switch it on and off; won't help with hum but will extend the life of the switch. Clean all the input jacks; spray, shove connector in / out several times.

General look-see:

Get a chop stick or other non-conductive similarly shaped object; gently bump and thump it around against everything; see if something's loose including all the little doo-dads on the circuit boards. Look for signs of arcing, burning, or excessive heat. If you have those multi-conductor connectors; use a little finger pressure to snug them up. If they can easily be taken apart, spray some gungie on them too.

Does this amp have a classic reverb can or is the reverb 'electronic'? If a can, it has inputs and outputs; same as above, spray push on / pull off connectors several times.

With luck it's the pot; otherwise it's likely to be an integrated circuit on a pc board...the fix is a new board....unless you (or your tech) is able to isolate the IC / transistor whatever...

Good luck!
 

Graham

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capnjuan said:
Potz first:

the pot shafts have a doink of grease

(do not put finger in your ear)

General look-see:

Get a chop stick

bump and thump it around against everything; see if something's loose including all the little doo-dads on the circuit boards.

use a little finger pressure to snug them up. If they can easily be taken apart, spray some gungie on them too.

Good luck!

This stuff is far too technical for me. :shock:
 

capnjuan

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The maintenance is the easy part; the hard part is eating a new pc board and the in-and-out tech charges because a 20 cent resistor or $2.75 transistor failed. The time to troubleshoot/repair the board is/can be the financial equivalent of a new one.

No easy solution; if you want a variety of tones and functions in the amp, you own the risk of component or sub-assembly failure. If you try to achieve tonal variety using pedals, there's the cost, stumbling, batteries, bending down to manipulate controls....

As teams might (but don't often) say about Mats Sundin; 'you can't stop him, you can only hope to contain him...'
 

zom-zom

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I'd initially check the cables leading to the reverb tank. If one is bad, or partly disconnected, you'll get hum. Could be very easy fix.
 

zom-zom

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capnjuan said:
Get anywhere with your D-25 Zom Zom?

Fedex did a damage report, sent it back to me for some reason.

Haven't heard the results yet, seller promises to refund me, they seem straight-up. I found another in the meantime.
 

Jeff

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Thanks everyone for your input, sorry it took me so long to follow up, I got a bit distracted over the weekend with Grampa duty. Oh, and there was all that stress over the D 70 on the local Craigslist.

I should have time tomorrow to wrestle the Roland onto the desk & take a look inside.

[img:450:338]http://www.imagestation.com/picture/sraid225/p9f7bd543542ab631203264fc1dbdc346/e9e45da3.jpg[/img] [img:450:338]http://www.imagestation.com/picture/sraid225/pbc4e18158417b302f883c147195961c9/e9e45db2.jpg[/img]
 

california

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I had a problem with my T5 and humming on the Cube a couple of days ago when the T5 was set on 3 and 5. I called Taylor, the tech told me to check my ground. The simplest way is when it is humming, touch the metal part of the cable inupt right where the cable buts up to the guitar. If the bussing stops, that is your problem. If so, make sure that the plug from the amp is properly grounded, going into a 3 prong recepticle. Mine was going into an adapter to a two prong which had not been attched to the ground screw on the outlet. Once I connected it, no more buzz.
 

Jeff

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I should check in & thank you guys for the help.

Whatever the problem is I must have absorbed enough here to chase it away. Wish I knew for sure where it went. Thanks.

The talk about pedals caused me to plug in the Crybaby Red gave me for Christmas. Crybaby technique I don't have, but for the first time I got a cool sounding distortion from the T 5 & the Roland.

Set the Crybaby about halfway, everything on the amp set midway + or -. Messed around transposing a blues scales from E to G. Dogone gear started funking right along, I was coming pretty close to playing Rock & Roll.

Starting to feel like I'm almost , just about, real close, to learning to play a bit.
 

capnjuan

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Jeff said:
...Starting to feel like I'm almost , just about, real close, to learning to play a bit....
So you want to be a rock and roll star,
Then listen now to what I say,
Just get an electric guitar,
Then take some time and learn how to play,

And with your hair combed right,
And your pants fit tight,
It's gonna be all right De Boids


As with many of us geezers, the pants can be an issue.... :roll:

I'm probably gonna take JP up on his suggestion re/ 'Black Box' - rack effects. Maybe I can get better by spinning knobs than I can by praticing and not interested in building a footboard populated with 'stomp boxes'.
 

john_kidder

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[quote="capnjuan] with many of us geezers, the pants can be an issue.... [/quote]

I was going to become David Bowie, but I just couldn't find the right pants. It's a shame how the little things that look simple hold us back so.
 

capnjuan

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Yeah; it's the Bowling Pin thing...

He/us: "Hi, my name is GeezerMan; I used to look pretty sharp!"
She: "Wow; I thought you were the 7 Pin"
 

jp

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capnjuan said:
I'm probably gonna take JP up on his suggestion re/ 'Black Box' - rack effects. Maybe I can get better by spinning knobs than I can by praticing and not interested in building a footboard populated with 'stomp boxes'.

So, here I am exercising my new "quoting skills."

I admit that I am a victim of this gear-crazy phenomenon, capn. I remember how easy it was when I could afford one guitar, and one amp. All I did was play. Lately I find myself surfing for vintage parts, trying to master eBay search criteria, and fumbling with my Fluke.

It's like my buddy, who's a master BMW bike technician once said, "After so many years of talking bike trash, and combing swap meets, and fiddling with carbs, I've decided that I like riding bikes a lot more than I like fixing them." 8)
 

Graham

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The Big Cheese said:
capnjuan said:
I'm probably gonna take JP up on his suggestion re/ 'Black Box' - rack effects. Maybe I can get better by spinning knobs than I can by praticing and not interested in building a footboard populated with 'stomp boxes'.

So, here I am exercising my new "quoting skills."

And doing a mighty fine job son, carry on. :wink:

You make us proud!
 
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