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OK I have the kit together and I am wondering if a couple of my voltage readings are OK...

Everything checks out very close to the table in the build guide except for the following:
V1 (EF86): Pin 6 reads 100v, guide suggests 131v
V3 (12AX7): Pin 8 reads 170v, guide suggests 160v (not too worried about this one)
V5 & V6 (EL84): Pin 9 on both tubes reads 212v, guide suggests 242v

Other possible "issues" I have:
I hear a definate "ping" noise when I turn the contour switch or when I tap on the chassis. I have read about EF86 tube and their tendency to go microphonic rather easily. Is this what is causing this sound?

I have a little bit of hum and some hiss, but not obnoxious levels of it, so I will look at that later. It might just be all the computer equipment and proximity of flourescent lights at my work area.

Is the 5k/8k "crunch & munch" switch supposed to have such a drastic impact on the overall volume of the amp? Wow, I was surprised when I heard the difference! The Vox setting is significantly louder. Not complaining, just wondering.

I had an issue with the contour control not working and I discovered I wired the volume pot to the wrong terminal lug. Switching the connection to the other lug fixed that right up.

I had a blast putting this together. Took maybe a little longer than I thought it would, but that's a good thing. I enjoy getting my hands dirty assembling electronics as much as I enjoy playing guitar. I'm going to reserve my assessment of the tone until I hear back about those voltages. But, so far...

anyone

I would say the voltages are OK. I suspect you are correct about the microphonics. Did you put the O rings on that were in the kit?
The crunch /munch makes quite a difference because in 8k mode it matches the impedance of the tubes. The difference in volume is noticeable.

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

Thanks for the reply.

Yes I used the damper rings on the EF. I'll get another tube and see if that makes a difference.

I'm really liking the amp so far!

What brand tube is it and was it new?

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

It's a JJ that I purchased from Eurotubes. He supposedly checks them all and rejects any that have a hint of being microphonic. Who knows what could have happened in shipping though.

I have another one of the JJ's and also the one I bought from TheTubeStore (RFD I think?) I just haven't had the chance to try them out yet.

It will be interesting to hear the tonal differences between those two. I found some of the newer Russian EF86 to be shrill sounding when compared to the older tubes.

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

Thought I'd jump in if you don't mind as I've played with the tubes in my TC15 a bit and figured I'd share my findings.

I started with an Electro-Harmonix EF86. When it went microphonic I tried an RFT from tube store. What a difference in tone! I wouldn't say the EHX was shrill but it was much brighter than the RFT, The RFT seemed quite 'dark' in comparison and I didn't like it at all on the 'matchless' setting as it seemed almost muddy. When it went micro as well I switched back to another EXH and the sparkle came back. I really liked the EHX but I can't get one to not rattle in my amp. When it rattled I went on the hunt for NOS Bugle Boys and when I finally found some I put one in and found it kind of sat between the two with the best of both worlds. Seems like the old EF86 tubes have a bit more 'body' and 'thickness' to me and are worth tracking down. Stick a fuzz or distortion pedal in front of it and it enhances the flavour instead of taking away which to me is one of the beautiful things about an EF86 channel.

I recommend before buying any NOS Amperex or Philips tubes (they are related) especially off of eBay or the likes to check out the links I added so you can familiarize yourself with the coding as it can make a difference.

http://www.tube-classics.de/TC/Tubes/Va ... pscode.htm or http://www.audiotubes.com/mullcode.htm are good places to start.

Channel 2 and the PI are JJ 12ax7s and I have no complaints. They just seem to work and seem to have a 'familiar' tone.

I had JJ EL84s for power tubes but one of those rattled in my amp so I switched to the Premium EL84's from the tube store and will never turn back. They sound great to me and when I turn off the Master volume and let them cook they just sing.

Tubes and tone are of course subjective but those are my personal results. I compared tubes without a lot of master volume as to avoid the power tubes coloring too much of the sound but at the end of the day its always the amp as a complete unit that matters.

Thanks for the review of tubes. I totally agree on the NOS Amperex and love the Bugle boys. I am trying a "gizmo" for microphonic tubes and will see how it performs.
We have been using 80's Russian Reflektor EL84Ms and like them a lot but they are hard to get.
As for the other channel, try Tung-Sol in the first position and then JJ .

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

I have Tung-Sols in there all-around right now (except the JJ EF86.) I have a bunch of JJ's lying around and in other gear including some gold-pins and long-plates. I think I will try that.

Been working too hard and focusing on getting a head cabinet built to monkey with the tubes lately. I have 10 days off here so after I sleep for a day tomorrow I'll see what I can try with the different tubes I have.

I will say that with the JJ EF86 and the Tung Sols in the rest of the slots (including the power tubes) my Carvin AE185 sounds a little "shrill" to me while my PRS Single-Cut sounds pretty darn amazing... which is somewhat of a surprise to me because the Carvin (my main go-to guitar) usually sounds the opposite... darker and richer due to the Koa top... while the PRS is a little "brighter" in my other amps with its maple top.

I'm trying something a little different with the head cabinet. I am making it out of solid pine and I am going to stain it kind of seafoam blue-ish color and sand it heavily so the grain shows through nicely. My tests on scrap wood look promising. Also may make an engraved LED-lit plexiglass front for it. Either that or a cream-colored stain front. I'm not an expert woodworker by any stretch of the imagination so hopefully my mistakes will add plenty of "character." If it turns out ugly I'll just tolex over it.

Looking forward to the pictures of the cab! Can't explain the tone change between the guitars tho..

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

I'm thinking it might have something to do with the fact the Carvin has active electronics (but interestingly from passive pickups - a rather unique design) and so it's output level might be a tad high. Reason I think that is that in the "high" input jack it is very pronounced but even in the "low" input jack, while less pronounced, the difference is still there to some extent. Might just be the tube choice too. I should know more about that tomorrow. I need to re-string my PRS McCarty (the solid-body model) and give that a workout too. I am thinking that guitar will absolutely sing in the neck position with this amp!

I glued-up the cabinet today, so tomorrow afternoon I am hoping to rout the edges, sand and put on a coat of stain. I'm pretty wiped-out though. It might have to wait until Monday.

I think your cab will look great with a transparent greeny-blue.

My guitar friend had my amp for awhile and he had similar results with his active guitar. He was running in the high inputs and in the "matchless" setting when I went to listen and it sounded horrible!

We switched to the low inputs and the "vox" settting and it tamed a bit of the shrill but then seemed to take on a "brassy" sound which I attributed to the super dense baffle material I chose for the cab.

When we plugged my dual humbucker strat it the magic came back to we switched to his Les Paul and then to his other guitars everything was good again.

Seems like the active preamps separation and ability to boost frequencies factors in somehow as to how it reacts with classic technology or something. Dropping the 180p cap on the channel volume to 100p or similar might help but a word to the wise is that I tried it (not using active guitars) and changed it back to the original (I only tried it on the 12ax7 channel) because I didn't find any advantage with my guitars.

No real solution but your not the only one to notice that. I honestly thought it sounded fine when I heard them play live and it was only when we were scrutinizing things (which is why I lent it to him) that it became an issue.

Some things just don't play nice together.

Hmm that's interesting that I am not alone with those thoughts. Thanks for posting that as it eases my mind a bit. I actually considered rewiring the guitar to passive or even taking the phase-shift switch and somehow seeing if I can convert it over to an "active/passive" switch since Carvin's active electronics designs all use passive pickups. Most of their active guitars come with a switch, a push-pull pot I think, to do the same thing but the AE185 is an exception because it has a peizo pickup in the bridge so it is full-time active. I just need to find a Carvin schematic to see how I may be able to do it. I'm sure they will send it to me if I asked nicely. If I just totally rewire it, I would have to buy or build an onboard peizo preamp but I would lose on-guitar mixing of the two signals, which is a pretty cool feature. I could live with that though because I rarely use that feature.

I am almost done with the cab. I decided for now to go with the blue stain on the outer shell and a painted "almond cream" face with chamfered edges that expose the plywood layers. I will most likely stain the chamfer black or leave it natural so there is an outline between the blue and the cream. The shell is stained and it looks real nice. I put the first coat of paint on the face so I am still a few days out from finishing up. It will be unique if anything else.

Really want to see your pictures. That sounds like a cool cabinet.

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

hehe... well don't set yourself up to be disappointed. I'm nowhere near an expert woodworker. In fact, I screwed up the rear panel pretty bad so I need to fix it. It's recoverable... I just need to build a fence and enlarge the cutout with a router. I hate working with skill saws. I can never get a straight cut with them even with a fence guide I always seem to mess up my cuts with them.

Question for ya... when you do your internal battens, do you screw them in from the inside of the cabinet or from the outside and use a finish washer?

We use internal battens or cleats only to attach panels to. We glue and then power nail them from the inside.

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

Gotcha... thanks.

Almost done... I really like it so far. Just need to finish-up the back panel, put its battens in and do some touch-up paint. Maybe tomorrow. I might just put a stainless metal screen over the back cutout I screwed-up and call it good.