coco wrote:
Did you find the cut control necessary with the 6V6??
I assume you're talking to me, since I don't see a John in the thread!
actually, I did not find the cut control necessary in the el84 lightning...I wanted to put the control on the amp to have some added tonal options. The cut as I have it (same as what's on the matchless clubman or cheiftan) adds a nice tonal difference...as I can get some darker moodier sounds out of the amp, that I wouldn't get with a regular tone control on a guitar.
coco wrote:
Did you change anything else on the tone controls - is it still 'interactive' like the Lightning?
It's still very interactive. I blame the 1mg trebble pot for that....if you download TSC, you'll see that the trebble pot tends to really govern the sound of the amp....if you changed the trebble pot to the traditional 250k, the amp would be a bit more traditional.
The added mid controls only really allows you to change the value of that 10k resistor in the lightning/vox tone stack. What seems to happen when I play with this new mid control, is that the mid control seems to more take over the role of the trebble pot and the trebble pot acts like a mid-sweep on a mixing board....it's very weird, but still very interactive.
I actually thought the original lightning stack was very interactive. I wasn't going to change it until I realized that I could very simply get the same results by turning the mid pot to a point where the pot is providing 10k of resistance...once that's set, the tone stack works like it always had...so it's a mod that isn't destructive.
One change I did make, which I didn't outline before (Because I don't feel it's relevant) is that I made some additional changes to the preamp to borrow more from the club deluxe. I was experimenting...and since these changes were easily reversible, I decided it was worth a try. The two major changes to the preamp were:
a) added a 1mg drop down resistor just after the volume pot. This probably dropped gain a hair...right?
b) changed the cathode resistor to 820 and bypassed it and the 22uf cap with a .1uf cap....probably increased gain a tad....
All in all, the above two changes did only very subtle things to the tone. Perhaps fattened it up a hair.....But not enough for me to go "Eureka" so I ended up just leaving them in...but if I pulled them and reverted back to the Lightning specs, I probably wouldn't notice too much of a difference! So thats why I felt it wasn't necessary to mention it....
coco wrote:
How would you characterize the sound now?
Well, first off, getting the doubled buzz out of the amp was what I really wanted...and it's gone now. Like I said, it's a WHOLE lot louder...and thats a plus too...
The amp definitely retains a rounder bottom end...and the top end is a little less sharp...but it's still definitely a 'lightning'...So the overall characteristics of the amp are still there in spades. I like the fact that the bottom end of the amp tends to be a tad fatter and rounder...since I can still dial that out with the tone controls.
The 6v6 is a superb tube...and whatever amp I build next, is going to employ them...I suspect I'm either going to be building mark huss's 6v6 plexi or s2's blackface...but whatever it is, Its going to use 6v6s.
coco wrote:
What B+ voltage are you running now?
I dropped the B+ earlier in the winter in an effort to kill the doubling buzz. It didn't work, but it *did* kill/reduce some other buzz which was probably some type of crossover distortion. Prior to the original transformation, the el84 lightning was running at 364v. In line with the 'change some things to Tophat', I've dropped the B+ down to about 344v with the use of Zeners. As I mentioned above, it definitely killed something undesirable....and an added bonus was that the amp sings a bit better...
With the added power boost I got from moving the screens line on the power tubes to the low side of the choke, I was less worried about losing a tad of power with dropping the B+....
coco wrote:
Congrats on what must be a nince amp and well done on the cab & faceplate. Looks very Pro!
Thanks!!!
Faceplates on the amp were done by Jeanne at BNP. She actually did the original lightning ones for me...The lightning one on the back is the same as the original...but the front, all I did was take the original corel file, more the knobs over one (so that the bass was sitting on the original hi input hole)....added the mid control and the cut control where necessary and sent the file to her for a reprint.
The cab was my 3rd cab done (I had previously done a head cab and 1X12). So I was started to get better at tolexing. It pales in comparison to the tolex job I just did on my sIII head (pictures to come soon). The tolex I had been using for most of my projects was really automotive vinyl with a very soft backing....it's very forgiving because of the softness and thickness...but also very difficult to line up or seam. So my cabs all have corner protectors to cover up the nasty corners...The sIII cabinet with the true tolex (supplied by trinity amps, thank you very much!) was alot easier to cover and a breaze to seam. My corners and bottom seam came out perfectly!