13 posts
Howie, I know you had a High Octane 5W head built not long ago and I know you love this thing.
My question is, how do the 2 gain controls work with just one input? Are you controlling the first two gain stages independatly and therefore balancing the two gain stages against each other?
I would have thought that a single gain control into the first stage would then determin what gain you achieved in the second stage etc;.
I'm Looking at this as a "prelude" build to the Torres Texas Boogie and also to have a second, Low wattage recording amp that will get my amp building skills a little further advanced before I take on the Torres project.
Your help and advice would be much appreciated.
Spud
DTR...HO Question?
Ok, sorry, but that's just a damn funny title! ;D
LOL!
Mine is the prior version, with only one gain control. The guy who I worked with on it has build probably 10 of them, and always builds the prior version. I myself was curious about the dual gain controls but chose to go the simpler route.
One of the things that kills me about the amp, is that while it's a higher gain beast, it sounds fabulous with the gain down as well. It has great clean tone.
The tone stack is subtle. I always liked the amp a lot, until I read that its similar (perhaps exact copy, I'd have to verify) of a Plexi tone stack, and that the plexi sounds best with B/M/T all cranked all the way up. I did that on the HO and boy did the amp come to life! I don't think I've ever turned anything down past 3:00 since.
The other thing is, the guy I worked with on this ordered all the parts for me because he was building two at the time. He always changes the value of two caps early in the circuit that roll off some bottom end, as he put it "to keep it from farting out in the bass since it doesn't have a lot of power." I will some time replace those and see if it farts out or not, because with a little more bottom the amp would be hard to beat. I think one reason he did that, was that he had used Hammond 125 DSE OTs in his prior builds, and I wanted a 125 ESE, which can handle the extra bottom end. Also, if I build another one or something similar, I'll use different caps and resistors. He's one of those engineering types and doesn't believe in "mojo." ;) I'd put Sozo caps in it, and carbon comp resistors in a few carefully chosen spots.
I have the full schematic and so forth for my version and can forward them if you'd like.
Thanks Howie. Is the schematic from AX84? If so, let me have the revision no. for the schem you used and I'll dig it out from there. If not, then yes please. I'd be interested to know where you would place the CC resistors as well. I have a whole bunch of these lying around and will use them if they match yhe values needed etc.
I'll ask the question about the two gains at the AX forum.
I,m torn between the High Octain and the straight P1 for this build but if as you say, the HO has a good clean sound and tone anyway, I might as well go for the HO and have the extra gain on tap.
FYI. The revision of the HO schematic I'm looking at is 08.05.07
I"ll get a version number off my schematics and let you know. And yes, it has cleans, just not much headroom, since the whole front end is set to break up early. Perhaps a P1 Extreme. I"ve considered building that one myself...
Andy,
I have PDF files of all the layout stuff etc, but not the schematic. I'll have to bring it in to work and scan it so I can put it up. Also, I've never tried my GE 5751 in V1 to see how the amp would work as a lower gain amp. I keep meaning too...
Any thought to the P1 or P1 Extreme?
Looking at it, I'll probably go with a straight P1 as a first build and see how I like it. I may then mod the thing to death and when I'm finally happy with it (read NEVER!), get some snazzy faceplates made up. I'm looking at figuring out what the mods do one by one and recording each change. The reason for this is I have found a very nice source for some lovely looking, and free!!! wood, enough to build about 20-30 head enclosures. If I can get the build process sorted, I'll build a few and then mod them to what people want. Spalted maple head cab anyone?.....No?...How about figured swamp ash, flame maple, or maybe a nice walnut......
I'm just getting into reading all the relevant threads at AX84.com so I can source the hard to get bits here in the UK rather than import kits and pay stupid shipping costs and extra duty etc. Unfortunatlly, the AX84 admin guys took about a week the approve my account so I can log on there. Something to do with an existing member being called Spud!!!!! ::)
I DO need you advise on one thing though. You mentioned that you speced a Hammond 125ESE OT so that your High Octain can handle the lows better before it starts to "fart out". As I'm looking at building a straight P1, and the tone stack is identical for both amps, would you recommend that I go with the ESE OT or stick with the standard DSE? If you look at the schematics for all three amps, only the P1X specs an ESE OT. I also noticed that the voltage on the primary side of the P1X is much higher (I presume this is to do with the fact that it uses a 270EX PT so that the plate voltage is higher to start with). I'll ask the question on AX84 as well.
Spud
Shit, thought this was about model trains. ;) ;D
Kabala — Feb 10, 2009Shit, thought this was about model trains. ;) ;D
Stuff that man......The only thing model trains are good for is target practice ;).
spud — Feb 10, 2009[quote author=Kabala link=1234049516/0#7 date=1234293765]Shit, thought this was about model trains. ;) ;D
Stuff that man......The only thing model trains are good for is target practice ;).
Uncle Fester? Is that you?!?
KrankZilla — Feb 10, 2009[quote author=spud link=1234049516/0#8 date=1234297326][quote author=Kabala link=1234049516/0#7 date=1234293765]Shit, thought this was about model trains. ;) ;D
Stuff that man......The only thing model trains are good for is target practice ;).
Uncle Fester? Is that you?!?
:)
Spud,
Your question will be better answered there, than here. LOL I'm still now great at all the calculations, even though Dar is trying hard to make me actually have some knowledge in these areas! HAHAHA
I try to retain what I read. I know that guys who really know their stuff, say to get the ESE in all the Valve Junior mods, for it's extra girth on the bottom end. I'm not saying the Hammond is THE best sounding tranny. It's not. They did an extensive test, and the WAY over priced Mercury was very slightly better in some areas (not bottom end, mainly a little purer) and the Heyboer was as well, but only VERY slightly and they cost more money. And the ESE had more balls than either.
I'll tell you something else if you just want to mod away and learn... got to Turretboards dot com and buy a Valve Junior turret board. No tone stack, but like the Marshall 18 watt "lite", the word is (and I'm buying 100% of it) that the ones with no tone "stack" sound the very best. I've heard Valve Juniors that would blow most people away. Pure, single ended Class A tone, with NOTHING in the circuit path can be a thing of beauty. A simple "tweed" tone control added can enhance it's tonal range. A gain switch can give it some range there. A negative feedback (switchable) can make sure it sounds great at VERY low volumes and retains focus when dimed.... etc... ;)
Seriously, if you want to do a kit from scratch. Buy a turret board, good trannies, some Sozos, and have some fun, bro!
p.s. Yer killin me with talk of these cabs.... Making me want to build that 18 watt Lite that is in my future...