Members 3 Headed Moses Posted October 17, 2011 Members Share Posted October 17, 2011 Originally Posted by jimmy624 is that a 5150 housing? It looks way better like that. I'm looking to do something similar to mine.-Jimmy- Cosmetic mods...:It also looks a lot LIGHTER as well Link to comment Share on other sites More sharing options...
Members 3 Headed Moses Posted October 17, 2011 Members Share Posted October 17, 2011 Also, I looked all over but can't find any of Kim's settings on this amp. Anyone know where they might be found? Link to comment Share on other sites More sharing options...
Members dicky sofa Posted December 24, 2011 Members Share Posted December 24, 2011 since there's been a bit of VTM talk around here I figured a bit of thread necro would be appropriate... Link to comment Share on other sites More sharing options...
Members Ovid9 Posted December 24, 2011 Members Share Posted December 24, 2011 Originally Posted by richardcouch since there's been a bit of VTM talk around here I figured a bit of thread necro would be appropriate... You're a good man. The VTM is currently getting lots of love and it makes me happy. I'm already seriously considering getting mine modded for the power amp out. Link to comment Share on other sites More sharing options...
Members naazrael Posted December 24, 2011 Members Share Posted December 24, 2011 Oh has there been? I'm still a big fan of my VTM, happy owner for two years now. Link to comment Share on other sites More sharing options...
Members tuccisbabe Posted January 28, 2012 Members Share Posted January 28, 2012 Hello amigos! I recently scored me a VTM 120 for $150 at a pawn shop. It's in need of a little love cosmetically, but it seems to function just fine. I can't wait to dig into it a bit... upgrade caps and possibly mod it out a bit. I think I'll recap it, keep it stock, and then see what it sounds like from there. Does somebody have a full copy of that PDF with the VTM mods? I would like to get my hands on the whole thing (I have the first page from another site). Thanks again for all of your work and info. Jared Link to comment Share on other sites More sharing options...
Members naazrael Posted January 28, 2012 Members Share Posted January 28, 2012 Oh, I have that PDF, but tbh, it's a crap set of mods. What do you want to do to your VTM, tonally? The biggest thing you can do for it, IMO, is bias it hotter. Mine was super cold. Link to comment Share on other sites More sharing options...
Members soundgardener75 Posted January 28, 2012 Members Share Posted January 28, 2012 Originally Posted by naazrael The biggest thing you can do for it, IMO, is bias it hotter. Mine was super cold. When I had it recapped, I asked my tech to bias it cold. I'm kinda strapped on money, so I figured the colder it is, the longer the tubes will last when I play for hours. Feel free to correct me on that.I sold my VTM 60 to fund my CRV's brakes. I'll keep this mind when I get a chance to own one again. Link to comment Share on other sites More sharing options...
Members naazrael Posted January 28, 2012 Members Share Posted January 28, 2012 It's been a while since I biased my amp (should probably check if it drifted actually...) but I remember that I found it be super cold. I remember that I basically doubled the current haha. Really came to life after that.I don't get as much time to play anymore due to school, but I used to clock in 5 hour jam sessions all the time, tube life is not a big deal. Link to comment Share on other sites More sharing options...
Members tuccisbabe Posted February 9, 2012 Members Share Posted February 9, 2012 Thanks for the reply, Naazrael.... I'm doing a little more research on this amp to figure out what I want to get out of it. As it stands, it sounds nice but really needs to be cranked up to get any gain out of it. I mean, REALLY cranked up. After opening it up, I found that the mid pot had been broken and replaced. It also has a repair on one of the ribbon connectors, which I understand is one of the common repair issues that comes up. So... it's been opened up and messed with a bit. Maybe something else is out of whack? We'll see... I appreciate the warning on those mods. I think I'll stick with the idea to upgrade components and recap and see what it sounds like stock. 3rdof3 sent me his info, so I may look into some of the value changes, but not go too far off track with modding at this point. I found a second 120 that's in much better condition... and it comes with a Peavey 412 cab loaded with Celestion G12K-85's. Cheap!!! I had never seen one of these amps before now and suddenly they're crawling out of the woodwork! Did anybody here grab that VTM 60 off of eBay... $199 and free shipping? That was tempting. Link to comment Share on other sites More sharing options...
Members tuccisbabe Posted February 15, 2012 Members Share Posted February 15, 2012 So,I picked up that other VTM 120 with the Celestion loaded MS412 cabinet. Looks like somebody really took care of it (that is, until they put it in pawn). It's in great shape, has a nice set of tubes and it sounds killer. I opened it up and found that a couple toasted wires had been fixed and one power cap replaced, but no apparent mods. Can't wait to see what it sounds like with a fresh cap job! After hearing what a good one sounds like, I went back to my first VTM to see if I could figure out my gain issue. When I swapped out all of the preamp tubes for new JJ's the amp came to life. I don't think it sounds quite as nice as my newer head, but it's in the right ballpark now. I'm sure it could use some new 6L6's, but I'm going to save up for new caps first. I'll probably keep the good VTM stock and maybe try some mods out on this other one. I like the idea of having one modded for EL34's... if I end up keeping both of them, that is. Anybody try out any of these mods and "fixes"? http://www.triodeamplification.com/VTMPEAVEY.HTML The Power PI voltage control looks like a cool idea. I'm not sure I want to go cutting traces on my boards quite yet, though. I think I'd consider etching myself some new boards if I tried any of those types of mods. A while back I had a Sovtek Mig 100, and I definitely like the VTM better. The cool thing is that I got two VTM heads and one cab for the price that I sold the Mig head for on eBay. Good deal! Link to comment Share on other sites More sharing options...
Members 3rdof3 Posted July 2, 2012 Members Share Posted July 2, 2012 I did the Adjustable Bias mod and tried EL34's in it. Sounded pretty close to a JCM800. I've also recapped and modified a few to get a more modern tone out of them. I'd be happy to recap yours for cost plus $50. I'm in AZ BTW. Link to comment Share on other sites More sharing options...
Members endofall Posted August 24, 2012 Members Share Posted August 24, 2012 Ok, so I scored a peavey vtm 60 for $180. I have taken it and practiced in the band with it. I know that it needs new tubes, and that the ones in it are very old. It seemed a little harsh sounding and thin at practice. It also has more gain than what I expected. I know that tubes can/might help with this but I got this amp to mod and tinker with. After reading this thread and several other threads about the vtm and modifications I have put together a couple that might help me out with it. First of I believe that I want to remove C2 on the pregain pot. To help some of the brightness of the amp. I am thinking of changing the slope resistor in the tonestack to 47k. This should shift the tonestack range and make it "meatier" I also want to add a .068 bypass cap in parallel with the 820 ohm resistor. This was listed as making the amp have more low mids And then add the Deep switch listed in this thread that adds a 44n cap in parallel to the existing 22n cap in the tone stack. I would also like to switch the amp over to kt88's or possible 6550's if it can handle it! What I would like to get out of the amp!?!? Im not really trying to get more gain. The amp has plenty, I wouldnt mind a little bit of a smoother gain structure. What I really want to do is reduce the highs in the amp, and shift the mids to a little bit more of a low mid style. I would also like more low end in the amp, and get into a bit more of a modern territory with this but I dont want it to be to much or sound bad. Should I go with a resonance control? Any thought or suggestions about modding this amp would be great! Link to comment Share on other sites More sharing options...
Members RedBear Posted August 25, 2012 Members Share Posted August 25, 2012 Hi endofall.Do you know what your current preamp tubes are. I have had two vtm's,a 120 and 60. Both had Chinese 12ax7's from 80's to 90's. Those tube's do tend to be a bit harsh and thin so check that out first. The new production Chinese are much more smooth than the old one's. I run Ruby 7025ss in v1 and v2 with a Sovtek 12ax7lps in the phase inverter. The stock power tube's were Philips STR 387 and one of the best 6l6gc ever,tight bass and lot's of headroom. With the cold bias setting these amps have stock there is a good chance the power tubes are still good providing it has not been gigged to death. What speaker and cab configuration are you using? Vtm's in my experience are sensitive to speaker choice. I have tried a bunch of different celestion's until I found the matching 412m cab with celestion g12k-85's.That cab matches my Butcher's and the Vtm's and sound best with most Peavey amps such as the Ultra series as well. You might want to look at beefing up the power supply filtering. I always felt that the Vtm was not as tight as my Butcher and is why I sold it and found another Butcher to have as a backup. I was talking to my amp tech and suggested this as a solution but I was happy with the Butcher so decided to go that way instead. Something to look into though. Link to comment Share on other sites More sharing options...
Members endofall Posted August 25, 2012 Members Share Posted August 25, 2012 RedBear, I believe that your right about the tubes. I do believe that it has the old chinese 12ax7's in it, but Im not sure what poweramp tubes are in it. I've played it through my Marshall 1960B cab with celestion g12t-75, and my Splawn Small block and and Big Block speakers. I will look into adjusting the power supply filtering. It would be very nice to have a tighter but larger sounding low end on this amp! Link to comment Share on other sites More sharing options...
Members RedBear Posted August 25, 2012 Members Share Posted August 25, 2012 The power tubes will have super 6 stamped on them,as well they will have 6l6gc usa stamped on them. You might like the bias mod as you can warm up the tone a bit. I did notice quite a difference on mine even with the super 6's,they are a very hard sounding tube but sound really good on higher bias settings. I think you might be happy doing the c2 and bias mod,and maybe some tube swapping. The Sovtek 12ax7lps is the best phase inverter tube I have used in a Marshall type circuit so far. Highly recommend that tube. You could always try a RFT ecc83 in v1 that tube sounds thick. You could run 6550 in the amp. That would give you quite a bit more low end and headroom, I had one of my Butcher's modded for them so I would imagine you could with the vtm. The only problem with any 60 watt amp is it will never have the headroom and bottom of a 120 watt. Link to comment Share on other sites More sharing options...
Members endofall Posted August 27, 2012 Members Share Posted August 27, 2012 Ok so I opened up my VTM today just to check it out and to get a look inside. After I opened up I noticed that it looked that someone has been in it, tweaking it a little. There is a resistor in series with C6 on the control board and on the back side of the preamp board their is a25f capacitor attached to the trace running to C2 and C5 on the preamp board. There is also a second capacitor connecting R9 and C4 of the preamp board. Does anyone know what this could be for? I have posted a couple of pictures of what I am talking about. Thanks for any help! Link to comment Share on other sites More sharing options...
Members endofall Posted August 28, 2012 Members Share Posted August 28, 2012 Bump for some help Link to comment Share on other sites More sharing options...
Members 3rdof3 Posted November 12, 2012 Members Share Posted November 12, 2012 The pics are too blurry to see for sure but, adding a resistor in series with C6 will just change the frequency that the Low pot shapes. You can just remove the resistor as long as the cap is .02uf. The other two caps were added to cut some of the high-end. you can remove both of them. Unless you like the tone of the amp, then keep it all! Link to comment Share on other sites More sharing options...
Members Pilot08 Posted December 7, 2012 Members Share Posted December 7, 2012 Hello everyone. I am thrilled that this thread is seeing action again, because I just got a VTM-60 and plan to mod it. I'm looking to do the dual channel mod.I have only VERY BASIC knowledge of electronics, but from what I saw on the diagram I need a DPDT relay, a rectifier, and some stacked pots. Another thing that I don't understand (and this is probably stupid) is there a jack for a footswitch? Do you use the jack for low gain?Another thing, the diagram does not show how to wire the stacked pots, which is probably obvious to you guys in the thread but I have no idea... Link to comment Share on other sites More sharing options...
Members Flux'D Posted April 4, 2013 Members Share Posted April 4, 2013 Hey guys! Always wanted a VTM and picked up a 60W'er a few days ago. Came with RCA blackplate 6L6's and a full compliment of Sylvania pre's. I haven't done any tube rolling in it yet, but the top end seems incredibly harsh to me. Is this the case with a stock VTM? And I'm assuming the "Bright mod" I read about is referring to this? The low end sounds.. a little odd I guess, I'm not sure how to describe it. Almost like the other frequencies overpower it. Also does anyone have a schem for the 60W version by chance? The man I bought it from works on amps and said he gone through the whole thing, I wanna see if any changes were made. EDIT: Is this a plug-and-play amp with the power tubes? Or do I have to adjust the bias everytime? I wanna pull the RCA's and hang onto them. Link to comment Share on other sites More sharing options...
Members IrvOnly Posted June 29, 2013 Members Share Posted June 29, 2013 Hey man( 3rdof3) . Do you still have your VTM. Im curious on how it sounds. The clip you posted sounds really good. I read that you had a tutorial on how to mod it(parts needed, diagrams, etc) ? how much will I spend doing so? Thanks Link to comment Share on other sites More sharing options...
Members the_shrews Posted August 17, 2013 Members Share Posted August 17, 2013 Alright, I'm diving in here!I've owned one VTM 120 for 10 years, and a second for 5 years. This, after seeing friends play with them since 1995 (His Hero Is Gone).I think they're GREAT stock, but now that I have the time, and two identical amps, I decided to go for a few mods I've read about for years (on one amp, leaving the other stock). I added a choke and took out the bright cap, making them both switchable. And I plan to do some more tone stuff, which I'll certainly need a few pointers on, but first I need some help with the bias mod if anyone has the time.I followed the image provided by 3rdof3 here: http://www.flickr.com/photos/3rdof3/sets/72157627999774416/ (10k limiting & 47k pot @ R8, 2k7 @ R9)The actual mod was a success (thanks 3rdof3!) and my bias is now adjustable (though I didn't check each socket to see if they were still matched). That said, the sweep is very limited. I have a hot set of Winged C's which I can adjust from 40-48, and the colder JJ's I can adjust from 12-20. It's my understanding that I should be able to get somewhere within 12-60, regardless of the tube. Is this correct? If so, which value(s) of resistor(s) needs to be changed to get more sweep?Secondly, some reccomend changing the screen grid resistors from 100ohm to 470, or 1K. If I plan to keep using 6L6s, is the screen grid resistor change necessary? If it's not a necessary mod for keeping the 6L6s, what difference in sound would it make if I changed them anyway? And what value 470, or 1k? I like the idea of being able to swap different tubes out, but also want to know what effect it will have on the sound of 6L6s, should keep them. Also, do the screen grid resistors have an effect on the bias sweep.Thanks in advance, I'm really looking forward to being a part of this thread/community! Link to comment Share on other sites More sharing options...
Members aaronsg71 Posted August 22, 2013 Members Share Posted August 22, 2013 Where's the bright cap? Link to comment Share on other sites More sharing options...
Members the_shrews Posted August 23, 2013 Members Share Posted August 23, 2013 C2 on the control board; just behind the pre gain pot. Link to comment Share on other sites More sharing options...
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