[HeadphoneAddict]

nice - My new Woo GES has the same type of finish and engraving and looks wonderful.

 

[BradJudy]

Quote:

Originally Posted by Pars /img/forum/go_quote.gif This really looks nice Amb... love the design elements in the panels. For the Sigma22 logo on the front panel, did you have to use HPGL to do this? Or does FPE's software support those fonts and character sets, etc.?

I don't know what AMB used, but FPE includes a Greek font for adding Greek characters like the sigma.

 

[wolf18t]

Gorgeous!

 

[Beefy]

I'm absolutely stunned at the work you guys have done for this. Your incredible work makes my money donation seem completely insignificant.

Can't wait for the final shots!

 

[amphead]

This was a very enjoyable build-meet, with Amb doing the hosting honors once again. I know you would have enjoyed it Russ, if you were in the area. Thank you Amb for your hospitality! Thanks goes out to Rockcod for much hard-work on the project, and thank you too Jrossel for your work helping me to construct part of the amplifier assembly, that Amb had done alot of the preliminary work on! This was a very successful event, and puts us closer to the testing phase, although there is more work required on the amplifier proper. Once again I really enjoyed the solder slinging with the build-team. Thank you very much donors, for making another build-meet possible!

Top view of the dual Sigma power supply.

Back of the amplifier.

 

[MASantos]

Guys, a little technical question: why isn't(edited) the PS case connected to the ground lug on the IEC inlet?

 

[amb]

MASantos, any piece of equipment that contains AC mains voltage should have its chassis tied to AC ground. This is to protect you from getting a shock if any live wiring or component inside is to come loose and touch the case. The chassis would shunt the lethal voltage to ground (and hopefully blow the fuse and/or trip your house wiring circuit breaker).

In this case, the body of the Schurter IEC is already connected to the ground lug, and it's mounted directly to the aluminum rear panel without isolation, so no explicit wire need to be added to make the chassis/ground connection.

 

[error401]

Wouldn't the anodizing isolate the connection? I'm pretty sure aluminum oxide is an insulator.

 

[amb]

Quote:

Originally Posted by error401 /img/forum/go_quote.gif Wouldn't the anodizing isolate the connection? I'm pretty sure aluminum oxide is an insulator.

The IEC's mounting screws contact the metal backing behind the plastic mounting flanges, and they are tightly screwed into threaded holes on the rear panel. I measure full continuity (0.2 ohms on the DMM) between the IEC's ground tab and the threaded pem nut on the front panel, which indicates that all pieces of the chassis are making good electrically connection.

 

[olblueyez]

Front Panel?

 

[MASantos]

Quote:

Originally Posted by amb /img/forum/go_quote.gif MASantos, any piece of equipment that contains AC mains voltage should have its chassis tied to AC ground. This is to protect you from getting a shock if any live wiring or component inside is to come loose and touch the case. The chassis would shunt the lethal voltage to ground (and hopefully blow the fuse and/or trip your house wiring circuit breaker). In this case, the body of the Schurter IEC is already connected to the ground lug, and it's mounted directly to the aluminum rear panel without isolation, so no explicit wire need to be added to make the chassis/ground connection.

I didn't remember that the body of the IEC was grounded. And I didn't type my question correctly above.

 

[krmathis]

Wow! Now I am more or less out of words...
This one sure looks stunning!

Really great work from the build and design team! ...not to mention those who have donated $$, parts, time, ideas, .. to make this possible. This one certainly will be special!

 

[wolf18t]

Oh boy, even if I don't really need it, this makes me want to build another B22 this time in two box and balanced. I would even buy the panels if there are eventually made available to a group buy. I suppose the chassis were sourced from Par Metal?

 

[n_maher]

Great work guys, truly something you all can be proud of.

If I may, I'd like to make one suggestion. Given the rather sedentary lives our amps tend to live I've gotten in the habit of removing the locking mechanism from XLR jacks. It can be a big pain in the butt to try and remove cables from behind a rack when they are locked in place and I've found XLR's to have every bit as much if not more clamping force than RCA type connections.

 

[amb]

I'm not going to be disassembling the XLR jacks. Unlike 1/4" plugs, XLR plugs are larger so there is more room to grab on to, and removal is a simple one-handed operation (press tab with thumb while withdrawing the plug with the remaining fingers). Btw, only the two rear panel XLR jacks have locking tabs. The front panel jacks for headphone connections are all "latching" but without the locking tab.