Manzamp!

[ic-racer]

I had a break in the Manzamp activity because some JBL 4311B speakers came up on Craig's List. I had to have these but they were pretty beat up so I spent a week fixing them up. I'm listening to them now... (before and after pictures)
[IMG:663:768]http://img.photobucket.com/albums/v670/ ... ile-10.jpg[/img]
[IMG:768:1024]http://img.photobucket.com/albums/v670/ ... file-1.jpg[/img]

[JazzGuitarGimp]

I had a pair of the consumer version (L100) back in the day. Brings back find memories!

[bluesfendermanblues]

I had a break in the Manzamp activity because some JBL 4311B speakers came up on Craig's List. I had to have these but they were pretty beat up so I spent a week fixing them up. I'm listening to them now... (before and after pictures)

Hi IC, Those are great speakers. I remember audiotioning them and other JBL's in local HiFi stores back in the day. Those speakers even had a particular smell. Sweet.

If you want to upgrade them toward a moderne highend sound, checkout this crossover kit: http://www.troelsgravesen.dk/JBL_L100.htm

I know the guy who makes them. He's the Danish Howard Dumble of HiFi speaker crossovers

[ic-racer]

I had a break in the Manzamp activity because some JBL 4311B speakers came up on Craig's List. I had to have these but they were pretty beat up so I spent a week fixing them up. I'm listening to them now... (before and after pictures)

Hi IC, Those are great speakers. I remember audiotioning them and other JBL's in local HiFi stores back in the day. Those speakers even had a particular smell. Sweet.

If you want to upgrade them toward a moderne highend sound, checkout this crossover kit: http://www.troelsgravesen.dk/JBL_L100.htm

I know the guy who makes them. He's the Danish Howard Dumble of HiFi speaker crossovers

Thanks for the link. Lots of good info there.
The JBLs made my workshop speakers seem weak, so I also did an upgrade on those with a new crossover and some cabinet mods.
[IMG768]http://img.photobucket.com/albums/v670/ ... ile-37.jpg[/img]

[ic-racer]

No pictures yet, but the 9 pin tube sockets are in. I got the front panel switches sorted out and the fuse holder is in. Very close to starting to connect the dots with wires and finish it.

Although it looks like the power supply is fully integrated into the PC board, actually the last 3 nodes are separated by wires that jump across and under the PC board. This is nice because I like to power it up in stages, so I can lift those connecting wires to do that.

[ic-racer]

Wiring the AC cable and on-off switch. All day job. Very tedious in the close space.
[IMG768]http://img.photobucket.com/albums/v670/ ... ile-66.jpg[/img]

[ic-racer]

I'll start posting pieces of the schematic as I go.
[IMG:481:203]http://img.photobucket.com/albums/v670/ ... Cinput.jpg[/img]

[oldmacman]

I know you're trying to be faithful to the original build, but if you're going to keep the line-to-ground cap, you should really use one rated Y2 that's designed to fail open. Mouser has them for less than a dollar (p/n 80-PHE850EB5470MB14).

[ic-racer]

I know you're trying to be faithful to the original build, but if you're going to keep the line-to-ground cap, you should really use one rated Y2 that's designed to fail open. Mouser has them for less than a dollar (p/n 80-PHE850EB5470MB14).

Thank you for the link.

[ic-racer]

Recent pictures:[IMG768]http://img.photobucket.com/albums/v670/ ... ile-69.jpg[/img]
[IMG768]http://img.photobucket.com/albums/v670/ ... ile-68.jpg[/img]
[IMG768]http://img.photobucket.com/albums/v670/ ... ile-67.jpg[/img]

[ic-racer]

Starting to wire the EL34 sockets:
[IMG768]http://img.photobucket.com/albums/v670/ ... ile-70.jpg[/img]

[Structo]

Man, that is one crowded chassis!

Is it the same size as the original?

Can't wait to hear what you think of this amp once you power up.

[ic-racer]

Man, that is one crowded chassis!

Is it the same size as the original?

Can't wait to hear what you think of this amp once you power up.

Scaling from the picture could be as much as 1/2" off. It seem like it needs another 1/2" of height. However, the 'standard' available sizes of aluminum stock in the next size is much bigger overall and thicker. Yes, Dumble may have had a special piece machined, but that seems odd. If one were to do that, why not put ends on it and use thinner material? Also, it could be that in the 1980s there was a larger selection of standard extruded aluminum sizes.
reproduction transformer does take up more space in the chassis.

It looks like the original Manzamp has the PT slightly off center and I figured it was to have more room to wire the Rectifier tube, but after wiring it I'd rather have more room by the switches. So, if I were to do another I'll center the PT in the chassis.

[Mark]

When were the Manzamps built?

You're right about the extrusion it is hard to know if there was a standard size and if this size is still used today.

The question I ask myself is, "was a chassis available when the Manzamp was built?"

[ic-racer]

When were the Manzamps built?

Based on the yellow resistors and the Manzamp listing in the 1990 Dumble price list, I put it in the 1980s. The Music Man speakers are from the 1980s also, I believe.
Manzamp = $8,500 express service
SSS = $8,500 express service.
ODS Head = $5,150 express service.

Something about the Manzamp made him price it the same as the SSS.