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Discussion Starter #1 (Edited)
Hi
right off the get go....I am not set up for pictures yet. 12X19X14 tall cabinet dark blue tolex with rust colour grille and a big wooden treblecleff logo ,gold paint edges, over cloth. chicken head knobs with red metal "factory" printed control panel at top back, hinged panel at back. gold paint lines and notes on upper front tolex......

Had the amp in to tech since March 7/07 for whatever it needed.
finally got it back but need assistance with a few things.

guestimated wattage 15W currently has 2 GT6V6C and 5Y3GTA rectifier.
new Weber 8" alnico sig series "champ" speaker. apparently this amp is a "55 tweed delux style."is bright sounding, works best with rosewood stratocaster or other darker sounding guitars"

because of the time delay and having to go through L&M for the repairs I am unable to have the tech answer and/or clarify for me.(doesn't return messages). did get some info with the bill.

it was suggested that "a 12" speaker really sounds great with this amp". new 8" is attached to the output transformer. don't know speaker ohms but is a 15W. how do I go about wiring this thing to a jack so that I can run a seperate 12" speaker. I would like the option of using both seperately if doable.( I will find out ohms later) ( must always have speaker load at all times)

I am learning bass guitar very slowly but have acquired a collection of guitars and amps over the past few years. the tech's description, following, needs to be put into grade school english for me please, I do not capice......

these are the current controls left to right: (as "originally labeled")
mike jack.....1st guitar pot 1-10....2nd guitar pot 0-10.....brilliance pot 0-10.....tone pot 0-10.....1st guitar jack....2nd guitar jack.

("quotes" from repair bill)

"the controls are very interactive, even changing the volume setting of the unused channel can greatly affect the sound (?). guitar 1 and 2 jacks feed the 1st vol control (guitar pot 1) and is stock triode channel from deluxe. Guitar 2 jack has slightly less gain" (ok I think I understand that I plug guitar into #1 guitar jack and control vol with guitar pot 1, don't think I need to use #2 guitar jack...?)

"Mike imput feeds 2nd channel and is pentode channel with more drive, fatter tone." (for mike or guitar or both???) (originally wanted to use for mike with mike imput adapter) (sounds like better for blues type guitar?)

"Brilliance control works on both the guitar and mike (channels?) (mike jack/guit 2 pot...guit 1 +2 jack/guit 1 pot.) (once sorted out i,m getting a label maker...LOL)

"The tone/on control only works on the mike channel" (haven't plugged in yet or messed with) ( really lost me on this)

any and all help is very much appreciated.
"lost in space"
RIFF
 

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This is really when a pic is worth a 1000 words (maybe 10,000 words in this case).

Hopefully somone will "recognize" your amp from the description.

I'm really curious.

Good Luck on getting your answers.

Dave
 

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Discussion Starter #3
OK reread my info and have relabled my control panel.

still need clarification:

1) former tone control is referenced by tech as on tone. checked and it does turn amp off and on with a click, but the dial also turns from 0 to 10. is it possible that besides being the on/off switch that it could also affect the tone for just the one channel?

2) I would like to install a jack for an external speaker. current speaker has an output tranny attached. need advise on wiring.

3) proper way to test speaker ohms.(unit off but still wired, single or series)

help please.
cheers
RIFF
 

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OK reread my info and have relabled my control panel.

still need clarification:

1) former tone control is referenced by tech as on tone. checked and it does turn amp off and on with a click, but the dial also turns from 0 to 10. is it possible that besides being the on/off switch that it could also affect the tone for just the one channel?

2) I would like to install a jack for an external speaker. current speaker has an output tranny attached. need advise on wiring.

3) proper way to test speaker ohms.(unit off but still wired, single or series)

help please.
cheers
RIFF
Mr. Riff, as a tech all I can say is that when you ask for help you don't make it easy!:smile:

If your amp was a car you'd be saying: " I've got an old car. It's got four wheels and a blue steering wheel. I want to replace the carburetor so could someone please advise how to do it."

You've given a general description that could fit hundreds of old amps. Likely it is a relatively uncommon brand, which makes it harder still.

Not trying to sound negative but without a lot more information you don't need tech help, you need the Psychic Hotline!:eek:

As Jonny Five said in the movie Short Circuit: "More input!"

:food-smiley-004:
 

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Discussion Starter #5
Yeah Bill, i know.....

but if you weren't able to understand the quotes from my repair bill imagine how confused i am...LOL

how about my 3 specific questions?

how about i box it up and send it down to you?

cheers
RIFF
 

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OK reread my info and have relabled my control panel.

still need clarification:

1) former tone control is referenced by tech as on tone. checked and it does turn amp off and on with a click, but the dial also turns from 0 to 10. is it possible that besides being the on/off switch that it could also affect the tone for just the one channel?

2) I would like to install a jack for an external speaker. current speaker has an output tranny attached. need advise on wiring.

3) proper way to test speaker ohms.(unit off but still wired, single or series)

help please.
cheers
RIFF
Well, I'll try!

1. Anything's possible! If that's how it's labeled, that's probably how it works. Lots of amps put the on/off switch on a control, usually volume but once in a while they used a tone control.

2. Jacks are tricky. I don't have any pictures and besides, there's more than one style of jack! It depends on which one you buy. We also have to decide if you want to run an external speaker by itself or at the same time as the builtin speaker. That will determine how we wire the jack.

3. The proper way to test speaker ohms is with equipment too damn expensive for the likes of us!:eek: There is no accurate common meter. Speaker loads are not DC resistances. They are complex impedances that consist of the DC resistance of the voice coil wire and the inductance of that coil while suspended in the magnet's field. These impedances lie in a range across the frequencies fed into the speaker. So you need a complicated bench test setup with special equipment.

There is a rough and ready test method that usually works ok. If you read the regular DC ohms of a speaker it's usually a bit less than the actual impedance. Speakers usually are sold in 4, 8, and 16 ohm voice coils. In common use we find that the meter when put across an 8 ohm speaker will read a bit less than 8 ohms but more than 4 ohms. A 16 ohm speaker will read more than 8 but less than 16. A 4 ohm speaker will read maybe 2-3 ohms.

There are special speakers that will fail this test method but for the ones we see in guitar amps this way is "close enough for rock and roll!"

Hopefully this is useful. If you do want to ship it down just send me a PM! Meanwhile, have fun!:smile:

:food-smiley-004:
 

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that first post of yours cracked me up bill lol.
i dont unnerstand whats going on here really, but my old riviera amp has the on/off switch on the tone control. you click it past the detent, feel it click, then you have the 0 to 10 sweep of tone control.
 

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Discussion Starter #8
Thanks Bill
will try the speaker ohms test this weekend. I have 2 amps to check (that I want to add external jacks to) and have an assortment of "known" ohms speakers for ohms trials. one of the amps has 2X8" wired in series and not clear in my head if this will affect the reading.

regarding the speaker wiring on the homemade: will also check out in detail and post again first of week.

Thanks
Fraser
after rereading my tech info he does say on/tone but curiously only for the #2
channel. from that I would assume #1 channel does not have a tone control?

cheers
RIFF

ps got another old tuber on the way. plan to pull it apart and perhaps learn some basics.
 
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