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Lol....We'll make sure you are compensated in some form for this one, too!!!!!!!!!!

Keith and Darrin... Great team work guys
Darrin, So how are you now wiring the inputs with the twisted pair? Signal and return wires to the tube socket with the shield attached at one end only, combining conductor #2 with the shield at one end?? Many ways you could go with that.

I have to agree... Foil wrapped with a drain wire is in many ways much easier to work with than servicing the braid in standard coax. Nick the foil with some diagonal cutters and it tears away pretty cleanly. You really don't even need heat shrink over the transition, although the drain wire is uninsulated and depending, you may want to heatshrink over that. The foil generally has better shielding coverage than braid as well

Guys, with this sort of production (more than one is production!) and your aversion to working in close quarters, you should consider at least partially building your amps on flat fixturing of some sort. There are a few gottchas to watch out for, but I've found workarounds for most of them. Some pics from last month here:
viewtopic.php?t=1340
Need to post some updated pictures, but you get the idea. If I can help let me know

Joe G

_________________
Some assembly required,
Brain sold separately...

Thanks. I've definately developed an addiction. Trying to talk Keith into buying another kit (but don't tell his wife that!!!




I'm using the two conductors for the two input jacks instead of using two separate shielded cables, so the shield/ground is shared between the hi & lo inputs for each set of jacks. Seems to work fine. I should throw a pic in here, shouldn't I...



I should clean up those ratty ends too.



Yeah. I built a couple using single conductor coax with braided shields and it was just a pain. Sounds like we agree on the reasons for going with the foil shield/drain wire. And using two-conductor shielded cable just makes it easier again for dual input jacks...one cable covers all!

So, to install, you you rip the foil away & solder the ground lead/drain. If it's easier you think, I'll soon make the change.

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

That be it man
Another little trick for foil or braided shield, and especially for removing the braid on the unshielded end...
Remove the outer jacket to slightly over your final service length, exposing the braid or foil. Hold by the braid and carefully pull the outer jacket back another 1/8" to 1/4' or so exposing that much more of the braid or foil. Now carefully clip off the braid or nick and tear off the foil up to the jacket (you can also cut off the drain wire at this point if it's a no connect at this end). Slide the outer jacket back up over the trimmed off shielding. Nice clean look without the whiskers of the braid showing or sticking into everything. If you get good enough at this you don't really need the heat shrink over it, but I happen to like the look of the heat shrink
Another pictorial may be in order Stephen!

BTW... This would be for PVC insulated wire only, like the RG174 coax for example. Not so easy for us Teflon® users!

Joe G

_________________
Some assembly required,
Brain sold separately...

You're the pro my friend - I'm just a tinkerer...a LAZY tinkerer! Any trick I can find to make my life a little easier...

I think it makes for a simpler & tidier job. It's tough to be neat when working with the ground braids for two coax cables. One could always ground the braids on the tube socket side though, which I haven't tried. That would clean up some of the mess on the jack side. I like the idea of having a common ground point though, so I ground everything on the jack side to the pre-amp ground. In fact, I used a single star ground on my 2204 build (except for the AC).

As I noted, I haven't had any noise problems with the three amps I've built this way. The bottom line is how effective you think it is for noise suppression. If using the individual coax cables give you better results there's no reason to change. Some of us just like to try different things for sh*ts & giggles...

Well, thank you Emo for doing all of the experimenting for us! Using a twisted pair had occurred to me since I have miles of the stuff in Teflon®. I was concerned about what may happen running the high and low input signals twisted together like that, particularly when jumping channels (which I think is pretty much the only time both inputs would be used simultaneously.
It sure would neaten up the Cliff jack wiring if the shields could be combined at the terminal strip at V1, although that goes against convention. Typically the shield is attached at the source end, but I think Deric® did this on his TC15 build (check it out on page 2 of the Lightning section). Please chime in Deric® if this is the case.

Experienced Teflon® users check this out...
http://www.mouser.com/catalog/629/831.pdf

Half way down the right column are Raychem solder sleeves with a drain wire. The center is a ring of solder with flux, and the two ends are a heat shrinkable potting material. It takes a lot of practice and a lot of heat but it's a really sweet termination solution for both Teflon coax or paired wire. I'll post some pics of it in the V6 Rackmount thread when I get there

Joe G

_________________
Some assembly required,
Brain sold separately...

Hmmm - I hadn't thought of that actually. I don't generally do the channel-jumping thing.

The first amp I tried this on was a single-channel 2204 so jumpering wasn't an issue. I also did it with a Trinity Deluxe and that thing sounded great regardless of what I did with the jacks.

When Keith and I really give his amp a good run we'll let you know how the jumpering works out. It depends on the signal path really. If jumpering just goes jack-to-jack it shouldn't be a problem. If it's going to the tube & back through the coax that may be another story. I don't have the energy or patience to figure that out at the moment!

OK - so I couldn't wait. I loaded Keith's amp up with some spare tubes I have kicking around just to see if there are any issues when jumpering with the way I have the inputs wired. Nothing noticable. A little bit of buzz, but with the extra wires running (and the jumper cable I used isn't exactly top quality) that wasn't surprising. It was barely noticable. My sIII does the same thing with the same cables and is wired per Stephen's layout so I'm not concerned.

However, I did notice a lot of hum on the TMB channel. It seemed to be centered around the master volume control. I though I had missed a ground or something so I double & triple checked. Looked fine. I used a jumper wire with alligator clips to test all the pre-amp grounds & no change. Chopsticked it too. No impact.

I was beginning to get frustrated, but then completely by accident I hit the boost switch...no more hum. Then my overworked little brain remembered that I had a very similar problem with my sIII when I first built it. I searched my e-mail (I remembered asking Stephen about it) and I found the solution...it was a bad tube in V2. I replaced the tube and everything's just fine.

Funny how I had the exact same (non) issue on 2 18w builds with two different tubes. Life's like that sometimes!

Funny......BTW Darrin....the tubes all showed up today. I'll drop them at your work tomorrow!!!

Oh goody. Cant wait to hear this review!! Fortis, send the family out to McDonalds!!

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Stephen.....am I hearing a faint "...it's time to get a TC-15 as well!".......maybe it's just me!

Keith

Thanks guys, that's good enough for me. I'm going to try a single twisted pair with the Alternate Cliff Jack Wiring idea in "Dressing Room"... Oh, in Teflon® of course

Joe G

_________________
Some assembly required,
Brain sold separately...

Well then, the Rock would be well covered now wouldn't it!!

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Well, we'd have to get a Deluxe over here too. The one I built was for a buddy of mine in Whitby...

I'm thinking he should drop over to my place to demo it - no family issues! It'll drive the cat nuts, but she's already loopy...

Just a suggestion...

Sounds good!!! I already dropped the tubes off to you (at work) anyway!

Keith

Yeah - the tubes are sitting on my desk. I can't wait to hear it with the 6V6's...

(time passes)

Just fired it up & everything seems to be working fine. The 6V6's are definitely more laid back & open than the EL84's, and not quite as loud. When I get some time later I'll wind it out a bit & see what we get.

As expected. Crank it and you should get some pretty creamy tones.

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Well, I just spent an hour ripping through Keith's amp with my stock SG Standard. All I can say is...



Let me say that again...



We need a bigger s**t-eating grin emoticon to describe this puppy! I tried everything from clean bluesy/jazzy stuff to classic rock to early QOTSA and this thing delivers across the board.

I will commend his tube choices also. The Tung-Sol reissues are my personal favorite pre-amp tube and I love them in both 18's I've built. I also like the JJ EL84's over the EH's I currently have in my 18. They don't seem to get as fizzy and are a little crunchier. The EH's are more open though, so they're a little nicer for the cleaner stuff. The EH 6V6's are nice, but I'd like to do a comparo between those, the JJ's and the Tung-Sol's. The Tung-Sols are supposedly even creamier & bell like and I think that would make this amp almost the perfect hybrid.

But I'll leave it to Keith to do a proper review...I'm REALLY looking forward to his reaction tomorrow when he gets to play through it!