12AX7 Channel (Random country riff)
EF86 (random country riff)
EF86 (random country riff #2)
EF86 (palm-mute distortion)
(Recorded with an Audio-technica condenser through a cheap preamp in a terrible sounding room)
I'm not huge on sound samples, since it depends so much on recording quality and the player. Not sure if you can tell much other than that it sounds like an amplifier that breaks with a certain character. I think it's hard to comment on how it sounds as a stock amplifier, since any one person might do something different in the build. Below are some of the high and low points of the building process and amplifier.
The Parts
Anyone who has built an amplifier from scratch knows that half of how the amplifier turns out is based on choosing the right parts for your purpose. Depending on your goals, you will make different decisions here. If you're trying to clone a specific vintage amplifier, you might go out of your way to acquire "obsolete" carbon comp resistors that are widely known to change value at different temperatures, paying as much as $3 for a single Riken or Allen-Bradley new old-stock (see the selection at Angela Instruments). So what was my goals with the 6D30? Create an amplifier that I can A/B various amplifier designs for a learning what kinds of circuits suit various sounds I want my guitar to make. If you're wondering why I don't just go amp shopping to figure this out, I just want to comment that it's really difficult to find out if you like an amplifier by playing it at a music store where there are people playing instruments all around you and sales guy trying to pitch to you why a specific amplifier is good. Even if you're lucky enough to be at a chill music store with a good sales people who are not annoying, I still find it hard to decide whether I like an amplifier until I hear it for a week or two or with the band I'm playing in. So what parts did I want for this amplifier? New ones that were relatively inexpensive, but not cheap and crappy. Weber excels in this category, and I think all of the parts met or exceeded my standards, except for the pilot light and tubes. Web forums had warned about the cheap pilot light, and I think this is relatively insignificant, although I will definitely replace this eventually. On the other hand, I think I understand why Weber does not include cool NOS-tubes: people oftentimes already have a preference, and nice tubes are $$$. Not to mention, who wants to plug in a high-dollar quad of Mullards into a circuit being tested? The stock tubes sound just fine, but they're not amazing. No big deal. The cabinet below is a pretty good example of the quality of workmanship that goes into the amplifiers:
Shag carpet not included.The Layout
The panel design and circuit board was way cramped on this amplifier, although I liked the separation of the power supply and tone circuit. I visited Bryce Gonzales (local Sacramento amplifier expert) at BG Electric to help me iron out some oscillation issues. As you can see in the photo below, he pretty much moved the entire tone circuit of the 12AX7 from the board up to the pots and removed the effects loop:
He explained these moves showing me how the signal wires passed near the DC voltage wires. Oh, of course: the magnetic field generated around the signal wire will be inducted in loops of neighboring DC wires creating an oscillating power supply to the tubes. After his help, the amp stopped making non-harmonic noises and sounded fuller. Nice!
The Speakers
Uhmm .. Freaking amazing.
The Future and other notes
I think the amplifier is perfect for my goal of having a lot of things in one place that I can A/B. The 6D30 is the ultimate amplifier as far as having many options inside of a single box goes. HI/LO gain settings, a cathode-fixed bias switch, load impedance switching, built-in bias meter, .. the list goes on. As far as becoming familiar with various sounds goes, this amplifier is an amp builder's dream. I think as it stands, I would compare it most to a Mesa amplifier due to the bells and whistles. Among amplifiers I've played, it has a super fast response where the attack of all notes is well-pronounced, quick, and loud. The highs produced by this amplifier are decidedly Vox-like but with more grittiness.
Basically, I think the amplifier as built would work well for a guitarist who likes a Vox tone at high volumes. I really like the EF86 channel, but I am probably going to tone down the 12AX7 channel a bit more. My main complaints on this channel would be that it always seems to have too many highs that get a little "ice-pick" like at times. This would be a good lead tone, but I play rhythm/harmonic guitar, so this sound is not very useful to me. No worries, I will change out some capacitors, reduce the gain (maybe sub in a 12AT7 ??), and dial it in.
The big question for me with this amplifier is volume. I love playing it, but it's too loud. I currently use an attenuator at half volume or so, and I basically always play this amplifier on cathode mode. I am wondering about redesigning the output stage for 2 tubes to avoid dragging an attenuator around. And that friends, is the fun of this amplifier: you finish it, and all the parts are there to mod it into something else :)
