[Now powdercoated] My very own Gyraf G7 build thread

GroupDIY Audio Forum

Help Support GroupDIY Audio Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Enchilada

Well-known member
Joined
Aug 24, 2011
Messages
323
Location
Australia
Hey guys,

I've already started two threads with questions regarding my Gyraf G7 build so instead of creating a new thread to document my build I thought I would re-claim this one and use it :)

I changed to the RK12 capsule for a while but I've now gone back to Tim's capsule. I've also now had it powder coated  and it looks sensational :D!

WhiteG7.jpg


History:
My first issue I ran into was regarding the transformer, Jakob has advised me that a Cinemag CM-2480 should work just fine.

My second issue (and the original point of this thread) was regarding the 7 pin mic insert thingo. I'm using two broken Cad Trion 6000 mics as donor parts to build my G7. I've removed the 3-pin XLR insert and was hoping I could get a 7-pin insert to replace it with. I ordered a male 7 pin XLR and was able to use the insert from it.

My third issue was with the voltage regulator. That's now been sorted and you can read the details below in this thread. Thanks Harpo for sorting this one out! :)

Fourth issue was with pattern selection. Figure 8 had the back side much louder than the front, Cardioid had the back side loud and the front much quieter but still audible. Omni had both sides basically silent. Using Tim Campbell's CT12 capsule. The problem was a damaged 1nF polystyrene cap.
 
Tried that, seems that the inserts I'm cables are different to the inserts in mics. My MXL 9000 (7-pin), MXL 603 and Cad 6000 all have exactly the same insert, it has a little brass grub screw.

I was hoping to find a part that could be directly swapped in.
 
I found some 7-pin connectors on Evil-bay that worked. The guy who sold them to me even sent me some other photos so that I could double-check to see if they were like the Switchcraft, and indeed they were.
They were ridiculously cheap (I think I got 4 for around $12 including shipping), but so far have worked great. I put one insert inside my MXL 9000 (seems those pins get broken a lot), and used the others in their entirety to make cables for mics.
I found them by searching "7-pin XLR".
 
Well there you go, the last couple I've seen are different. Thanks for the tip! I'll have to keep an eye out for 7-pin connectors with grub screws.
 
Hey guys, now that I've hijacked this thread to make it my own build thread for my Gyraf G7 here's a photo of the PCB in the mic body, etched but not yet drilled. I also held the mic in the sun so you can see my edge terminated C12 style capsule.

DSC_0183.jpg


DSC_0182.jpg
 
The complete body  ;D. Now I just have to wait for caps, resistors and transformers to arrive in the mail and I can finish the job.

DSC_0187.jpg
 
Wow, looks great! I'm a bit of a novice (and new to the forum) but am just about to begin the same project, did you use the components exactly as listed (apart from the transformer) or did you upgrade any?
 
Thanks guys, it looks great it person too! The paint is White Knight "Squirts" quick dry gloss enamel. The colour is Metallic Charcoal.

@Baxmcc, I'm still waiting for components to arrive but I haven't used the components in the BOM from Jakob's web site. There seemed to be some errors with it although I could have just been reading it incorrectly. When ordering components I just followed the schematic.

Kris
 
Quick update on my build, there was a lot of wasted space inside the so I've condensed it all together and now I've shaved 4.3cm (1.7 inches) off the total length of the mic. I'll post new pics soon.

Also, if anyone who knows about capsules, I'll have one of Tim Campbell's C12 capsules coming in the mail soon. I was planning to use it to mod an Apex 460. At present, I have one of the microphone-parts.com RK-12 (C12 style) capsules in there. I was originally hoping that having the RK12 in the G7 would be better because it's a better circuit and Tim's capsule would go further in the Apex 460 but now I'm starting to doubt my decision. Any thoughts???
 
Enchilada said:
Quick update on my build, there was a lot of wasted space inside the so I've condensed it all together and now I've shaved 4.3cm (1.7 inches) off the total length of the mic. I'll post new pics soon.

Also, if anyone who knows about capsules, I'll have one of Tim Campbell's C12 capsules coming in the mail soon. I was planning to use it to mod an Apex 460. At present, I have one of the microphone-parts.com RK-12 (C12 style) capsules in there. I was originally hoping that having the RK12 in the G7 would be better because it's a better circuit and Tim's capsule would go further in the Apex 460 but now I'm starting to doubt my decision. Any thoughts???

I don't know about the other capsule but I know CT12 is amazing and deserves the best possible home. That's why I'd put it in G7.
 
OK, I'm in need of a little help with my PSU.

It's putting out 165V ish on the +160V pin so there's no problem with that side but the heater voltage is 14.4V with no mic plugged in. When I plug the mic in it dropps way down to only 1.5V  :eek:.

EDIT: Just checked after another couple of minutes and it had further dropped to 1.2V. As soon as I unplug the mic is jumps right back up to 14.6V.

EDIT2: The tube doesn't glow :(
 
What's the voltage before the regulator mic plugged and unplugged? Maybe the transformers don't give enough juice or the regulator gets too hot?
 

Latest posts

Back
Top