Hello All,
I have just joined this forum being a new owner of an old amp as above. The sound is exactly what I am looking for, and every time I play it I undergo a great melting moment and have to do a long breath out after playing to "recover". Joy.
Some questions.
This amp has a low/high control. Will it shorten the life of the tubes if used in the low setting? I have read somewhere that it could be an issue, but cannot imagine why it was incorporated if so.
It has also been modified in the past. The phase inverter (?) .valve has been removed, and the diagram with the tube layout has had that valve scribbled out. Whilst this does not concern me as the tone is so good, I am interested in what has likely been done.
I have found that although the trem sounds great, it does take some of the full tone away. Is this to be expected\? I find that an increase in volume can make up for this.
The speakers have been replaced at some time by two Celestion 25W G12M's. Although slightly under powered for the combo they do sound good. I will be careful with volume, but seem to be coping very well at volumes I consider loud, and that is coming from a history of AC30 use.
Lastly the previous owner had a waterproof ON/OFF HI/LOW switch put in as there was some issue about moisture ingress?
I have tried to research these topics but have not found any satisfactory answers, so apologies if they have been covered before.
This is one great amp.
Thank you for any enlightenment.
Richard.
Fri, 09/22/2017 - 07:22
#1
Let's start at the beginning.
Let's start at the beginning. NO-it will not shorten the ttube life running in low. From what I remember, you really don't notice much difference in low and high in the converted amps. I had one. They MIGHT distort a little sooner but it's still pretty damned loud first. For what was done, if you're interested, I have the instructions for field repair and conversion of the amps with PI tube to SS driver. There are a LOT of steps but the major one is the conversion to being a cathode driven amp and the installation of the SS driver board. The Trem. There IS an adjustment for the trem intensity on the main board. Might need a tweak. Speakers. If you ARE running on low, you are roughly half power so that's 32.5 watts. your speakers are safe. power switch being water proof. I have NO idea why that was done. there's NO moisture problems so I'm assuming (and we ALL know what that means) that the guy just HAD one of those switches and used it. there. That's my opinion and I'm sticking with it (unless somebody smarter like Lars or Steve jump in!) Mike.
Thank you for that precise
Thank you for that precise answer, I will now play with the low setting. Of note I have found that the OCD pedal works best with this (for my style). Any fuzz recommendations?
Thanks again,
Richard.
Not really. I usually build
Not really. I usually build fuzz's. I Also like the Rocket Animal series of distortions (since I've built two!). If not built, all my stuff has been modded by me. The two Boss BD-2's are both modded in different directions. One is more bassy and over the top and the other is modded for more mids and upper mids and smoother. I just can't leave ANYTHING alone! Mike.
Pedals
Thanks Mike, going off topic but.....
I now run a Big Muff (old large box) into the OCD. Volcanic! Awful without OCD. I am now creating a larger pedal board (not that I have many) to accommodate said pedal..
Thank you for your comments.
Richard..
Forget my last message, I
Forget my last message, I must have had a weird ear day. OCD into Muff retains top end. Our hearing is interesting, it sometimes requires time to adjust with experimentation.
Even more off topic. Sorry.
Richard.
Speakers!
More news for me. The chap who I bought the amp from has unearthed the original square magnet speakers. It seems to make sense to buy them. I have an old closed back (heavy) Marshall style 2X12 cab that I will alter to be open, and try them out in this.I can then compare the tone to the G12M currently in the amp. The racket when run as an extension cab as either a 4X12 stack configuration, or spread apart is going to be just great. I have a brilliant neighbour.....
Richard.
212 65
Hi, desperately need schematic for unconverted 212-65. 12ax7 preamp/rectifier(?). Machine redplates both power tubes. Power tranny weepy. Suspect bad coupling caps. (power filter caps?) Does not blow fuses. 120 cycle hum, no output. Can you supply correct schematic? THANKS Found several online, but all are of the transistor model...
212 65
Sorry RED plates, but only on high setting..I may have a candidate for the "Hall of shame" because someone has fitted Peavey Scorpion pluses. They even tore off the grill cloth and installed the Peavey Cages..LOL
Should be in this file for
Should be in this file for the 2475-65. have a look.
http://pacair.com/mmamps3/downloads-and-resources
212 65
Thanks 210, I have that chart, but it doesn't show the 12ax7 phase inverter tube..unless I'm missing something..which is highly likely. Machine has no output except hum, scratchy pots, but seems to draw current correctly in the "low" position. This would seem to indicate failed coupling caps? However, Switching to high, even in standby, shows dead short, and redpates tubes, Removing tubes still shows short in "High"..any ideas..I will take some voltage reading at the pins today. For what it is worth, the power tranny has some weepiness (wax?) Help help LOL