Ampeg Squareback wiring question

[sleepy_monkey]

Color’s aside, the standard is, all the green dot terminals are connected together and the wire goes to ¼” jack tip. The other speaker terminals are connected together and go to ¼” jack sleeve.

It would be a good idea to test the polarity of the connected speakers. Do a 9V battery test. Plug a speaker cable into the 1/4” jack. On the other end of the cable, connect battery [-] to the plug’s sleeve. Momentarily tap the ¼” plug tip to battery [+]. All the speaker cones should move outward. If any speakers cones move inward, reverse the those speaker connections.

So that would mean the green wire is the signal since it goes to the tip?

I guess as long as I do the battery test it will determine +/-.

 

[agedhorse]

Yes, do the battery test.

 

[beans-on-toast]

So that would mean the green wire is the signal since it goes to the tip?

I guess as long as I do the battery test it will determine +/-.

One speaker terminal is signal [+], standard it the terminal with the dot; the other speaker terminal is the return [-]. So both wires carry signal.

You don’t know if the wiring was changed so inspect and test. Old terminal connectors can be loose or oxidized. Be very careful, especially with tools. You don’t want to slip and punch a hole through the cone.

 

[agedhorse]

Both wires carry current, the minus wire ends up connected to the amp's ground inside the chassis. There will be no voltage present on the minus wire.

 

[sleepy_monkey]

One speaker terminal is signal [+], standard it the terminal with the dot; the other speaker terminal is the return [-]. So both wires carry signal.

You don’t know if the wiring was changed so inspect and test. Old terminal connectors can be loose or oxidized. Be very careful, especially with tools. You don’t want to slip and punch a hole through the cone.

Thanks for the info. This was correct. The green dot on mine was [+].

Did the battery test and one speaker was out of phase…ironically it had a sticker on it from a speaker rebuilder…so I guess when it was reinstalled they just reversed the wires.

Good news is that all the speakers work…ran some music though them just to check. Now to get that SVT head running…and decide vinyl cover or Duratex.

 

[agedhorse]

I bet it sounds a whole lot better, eh?

 

[beans-on-toast]

Thanks for the info. This was correct. The green dot on mine was [+].

Did the battery test and one speaker was out of phase…ironically it had a sticker on it from a speaker rebuilder…so I guess when it was reinstalled they just reversed the wires.

Good news is that all the speakers work…ran some music though them just to check. Now to get that SVT head running…and decide vinyl cover or Duratex.

Good news! You always have br methodical and sweat through all the details.

I’ve recovered a lot of amps. Old cabinets can be funky. By that I mean issues with the laminations, out of square. It’s detailed work because the wood requires a lot of prep, round over edges and the front knees fixed on SVT’s. It has to be flawless before any skin can go on. I think that I would try Duratex if I ever did another Ampeg cab. It still requires all the wood prep but the rest is easy. And if you damage a Duratex surface, it can be touched up with a brush.

Here is a four part reskinning tutorial of an Ampeg SB-12. The same basics apply to any cab. Blue check is particularly difficult because the squares have to align. It takes a square cabinet and perfect vinyl positioning.

https://www.talkbass.com/wiki/roberto-s-xoir-1966-sb-12-cabinet-restoration/

 

[sleepy_monkey]

Good news!

I’ve recovered a lot of amps. Old cabinets can be funky. By that I mean issues with the laminations, out of square. It’s detailed work because the wood requires a lot of prep, edges and the front knees fixed on SVT’s. It has to be flawless before any skin can go on. I think that I would try Duratex if I ever did another Ampeg cab. It still requires all the wood prep but the rest is easy. And if you damage a Duratex surface, it can be fixed with a brush.

Here is a four part reskinning tutorial of an Ampeg SB-12. The same basics apply to any cab. Blue check is particularly difficult because the squares have to align. It takes a square cabinet and perfect vinyl positioning.

https://www.talkbass.com/wiki/roberto-s-xoir-1966-sb-12-cabinet-restoration/

Thanks. I put tolex on a Bassman 135 head once and while it wasn’t overly difficult, it also was an 810! I have the cabinet stripped down…definitely a lot of dents/dimples/chips, etc. I plan on filling all of those in and then seeing how it feels overall. I was leaning towards Duratex or the Behr Deckover, but SAE some vinyl at Hobby Lobby that looks close enough to old school tolex that I figured I could do that. My hesitance with duratex, etc is that if I ever did want to tolex it then that would be a PITA to take off.

The good news is that I’m not into the cabinet/head for much (yet).

Duratex/Behr Deckover might be the answer. It would surely be a lot easier. And this is something that will be sitting in my basement.

 

[Redbrangus]

I'd advise against using vinyl from a hobby shop or fabric store -- it may look similar, but it isn't likely to be as durable as the vinyl fabrics available from speaker cab supply companies like >>> Mojotone or >>> Speaker Builders Supply. You only need a couple of yards, so don't compromise on the quality of the fabric.

Having said that, I'd use Duratex or some other textured paint.

 

[beans-on-toast]

Thanks. I put tolex on a Bassman 135 head once and while it wasn’t overly difficult, it also was an 810! I have the cabinet stripped down…definitely a lot of dents/dimples/chips, etc. I plan on filling all of those in and then seeing how it feels overall. I was leaning towards Duratex or the Behr Deckover, but SAE some vinyl at Hobby Lobby that looks close enough to old school tolex that I figured I could do that. My hesitance with duratex, etc is that if I ever did want to tolex it then that would be a PITA to take off.

The good news is that I’m not into the cabinet/head for much (yet).

Duratex/Behr Deckover might be the answer. It would surely be a lot easier. And this is something that will be sitting in my basement.

I use Marshall Black Levant vinyl on SVT’s. You can order a sample swatch from Antique Electronics.

Invalid Link Removed

The layout to cover it is an important question. Ampeg used panels designed to economize. A better approach is to do what Mark did here by wrapping. There’s less seams. I don’t recall what vinyl he used.

Thread 'Building an Ampeg SVT-810E'

Jul 6, 2014

A couple of years ago I got it in my head that I wanted to build a copy of an Ampeg SVT-810E. It’s not something that I have a pressing need for but I tend to get the occasional odd-ball project idea stuck in my head and it nags at me until I finally act on it. Well, I’ve finally decided to start working on this project. I will say from the start that there may be time lapses in my updates on this project as there are other things that I really do need to be working on but hopefully I can keep this moving along too.

I will be using Baltic Birch plywood for this build. That will not...

• Vintage-Blue
• Replies: 234
• Forum: Amps and Cabs [BG]

• 

 

[sleepy_monkey]

I use Marshall Black Levant vinyl on SVT’s. You can order a sample swatch from Antique Electronics.

Invalid Link Removed

The layout to cover it is an important question. Ampeg used panels designed to economize. A better approach is to do what Mark did here by wrapping. There’s less seams. I don’t recall what vinyl he used.

Thread 'Building an Ampeg SVT-810E'

Jul 6, 2014

A couple of years ago I got it in my head that I wanted to build a copy of an Ampeg SVT-810E. It’s not something that I have a pressing need for but I tend to get the occasional odd-ball project idea stuck in my head and it nags at me until I finally act on it. Well, I’ve finally decided to start working on this project. I will say from the start that there may be time lapses in my updates on this project as there are other things that I really do need to be working on but hopefully I can keep this moving along too.

I will be using Baltic Birch plywood for this build. That will not...

• Vintage-Blue
• Replies: 234
• Forum: Amps and Cabs [BG]

• 

Wowza, what a build thread on that 810…incredible. Maybe I will just use Duratex…haha.