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surgevw

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Everything posted by surgevw

  1. It is a one-off built by Ruetz. I got it from him mostly built. Made for a tweed style amp, I think. Solid state rectification, single pre-amp tube, phase inverter and duet of 6V6-Ss for power. I *might* have enough heater power to install a tube rectifier. Oh yeah, it has bass/mid/treb tone pots. Pretty basic. I posted a URL to the schematic a while back. I really like the #2 6V6S duet. Me and my Dad made a cabinet. 3/4" birch plywood. It has a (16 ohm?) 10" Peavey Blue Marvel in it. Not my first choice, but it sounds good. The power brake is a series parallel setup that looks like 7.X ohms DC to the amp. It should turn the approximately 18 Watts out into 2-3 Watts to the speaker. I couldn't get specs on the speaker, I was aiming for low efficiency, like 89-93dB @ 1 Watt (no brake), but I really don't know what it is. P.S. 'Natural' reverb in an empty warehouse is pretty cool!
  2. It has been some time since I posted, but I finally got the chance to exercise the tube selection Myles made for me some time ago. I got some #2 (soft?) Groove Tubes 6V6S outputs for push pull, and a SAG-12AX7-MPI and a 12A*7 preamp (not sure whether I installed the 12AY7 or 12AX7 there). With a handmade resistive and inductive power brake/hotplate, it sounds great wide open, and not crazy loud. I was playing for 45 mins and my ears didn't hurt. My guess is over 85dB, but under 100. The tone? Think SRV distortion on 'Pride and Joy' I am very happy with it. Thanks again to Myles and the help I got from Groove Tubes on the phone!
  3. I normally lurk in the guitar forum but headed over here. I am interested in buying an inexpensive synthesizer and wantoed to learn more. I play a little guitar and sing a little and always wanted to play synth/piano but never got around to it. I have been experimenting a little with GarageBand on my mac and thought a synth could be fun and could help with my musical knowledge too. Guitarists aren't always known for being strong on music theory Thanks, and is there somewhere I should look for info on lower-end keyboards?
  4. A report back: Installed a 12AY7 for preamp, a 12AX7-MPI for phase inverter, and amatched duet of the new 6V6-S output tubes in a #2 hardness. Downstairs neighbors are gone, so I fired it up. I still need earplugs, but at #7 on the dial I can go into nice overdrive. #8 on the dial and it gets more agressive with sustain. #9 and I can get crazy breakup. NICE!!! If I had a room where I could play 15 feet from the amp, I probably wouldn't need hearing protection (I am paranoid about this) I wonder if a tube rectifier might add some compression to give a bit more sustained overdrive, as it is more pick-attack based right now. Just thinking out loud, and not sure I will try that. I think I have done about as well as I can with this amp with just one pre-amp tube. Thanks again for all the help, Myles! Seth
  5. Ok, I (finally) found an online shematic for my amp. I have a prototype Ruetz Z20 http://www.diyguitaramp.com/z20_full_schematic.gif or the webpage http://www.diyguitaramp.com/z20.html As of yesterday I installed a 12AY7 for the preamp and a 12AX7-MPI for the phase inverter. Haven't gotten the 6V6-S duet yet, have 6V6EH duet in there right now. All this drives the (16 ohm nominal) output into a 8 ohm 10" Peavey Blue Marvel run with a series/parallel resistive & inductive load that eats ~5/6 of the output power. DC resistance of the setup with load and speaker is 14.5 ohms. Myles- does this change your opinion on your suggestions any? Thanks, Seth
  6. Myles- As I have a diode (versus tube) rectifier, then I assume that handling higher plate voltages is a good thing. I wasn't looking for more power, necessarily, but I am looking forward to trying them. Seth
  7. Myles- Called Groove Tubes (no decent local deaters) and ordered some 6V6-S tubes, in a #2 or #3, a 12AX7 Matched Phase Inverter, a 12AY7 for preamp, and just so I have one, and ECC 83(?). Will let you know how it goes. Thanks for the suggestions. I ordered from Rick- he mentioned the 6V6-S as being new. Thanks, Seth [/qb] Seth, Lots of wrong directions here.... The 7025 is the brightest of any of the 12AX7s. The "red" 6V6's are the hottest .... BUT will break up the LATEST.... and .... you better check the bias as the reds (8-10), run VERY hot. On rating numbers: Basically, a #1 will distort sooner, and a #10 later. If, for example, with a mid range tube, say a #5, makes your amp start to break in the output section at a volume setting on the amp of "4", then with a lower number tube, like a #2, your amp would have a same sort of break into output distortion at say a volume setting of "3". With a higher tube, such as an #8, then you amp would stay clean to about perhaps "6" on the volume.
  8. Thanks for all the help Myles! I found a box for the 6v6 tubes, it says Ip: 39 and Gm 3900. I am assuming 39mA of plate curent and a gain of 3900? Looks like I am going to order some different tubes soon. Thanks, Seth
  9. Thanks for the suggestion. The local store didn' t have a 12AY7, so I will have to order that and a matched phase inverter tube. They had a Groove Tubes 7025, so I picked that up to try, too. They had Groove Tubes/Fender 6V6 "reds" so I popped those in on the output. I think they are quieter and distort earlier. They smell a bit, too as they break in. The shop guy said the reds were the "hottest" and would overdrive the earliest. Nothing ventured, nothing gained, and now I have some spares. Thanks, Seth
  10. No problem. If I get a chance, I will post a schematic. If not, I will try some different tubes anyways. Can't hurt much other than the wallet. And maybe I will build a tube rectifier stage, too. Thanks, Seth
  11. Perhaps blistering the paint was harsh. It was clean but too loud. I built a brake for it, so the speaker now only gets about 16% the power it used to. At least I can move the volume knob now so that all the change isn't in the first 30 degrees of motion. Maybe my best bet for overdrive is something like a tube overdrive pedal until I have a rehearsal space where I can crank this thing up. Seth
  12. So I have a scratch built tube amp. 12AX7 preamp and inverter, diode rectifier, 6V6GT (from electro harmonix) push-pull with a transformer set for 16 ohms. I thought it was 8 ohms and have a 8 ohm Peavey Blue Marvel in it. I am going to add 7.5 ohms of resistance and a couple hundred microhenries in series to take care of this "issue" and quiet it down a bit. My problem I can't get even a warm overdrive without peeling paint of the walls. (BTW, I play a Strat, hard maple neck, with single coils). I am looking for at least a little bluesy overdrive. After reading the book you helped write, and surfing your site some, it looks like 6V6-R output duet, maybe a 12AX7-C for preamp (?) and something different for the inverter (a 12AT7?) Does this sound like a good starting point? Any compelling reason for a tube rectifier, if I wanted to do such a mod? Oh yeah, I have a single 5Y3 Sylvania USA rectifier tube kicking around, too. Thanks, Seth P.S. I am gonna try to close the thread I started and leave this here.
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