Classic or Skyliner? Rebuilding a VHT D-50

[dorrisant]

Thank you Mark! that was informative...

Big parts orders are on the way. Wow. I can't believe how much I have read and learned in the past few days... starting to see things much more clearly now. I'll be ready by the time the parts get here.

[dorrisant]

Sorry for the long wait. I have the last (maybe) of the parts coming in this afternoon. I have installed what I think are some vintage parts in there and will be able to take/post clips in a bit. Noise requirements say no for a few hours, then all hell can break loose.

NOTE: I took these pics before I realized that I had 180k going to the OD trimmer. After this, I lifted the 180k and added 100k in series. 270k 1W CFs are still en route.

[dorrisant]

Late as usual but here we go...

I ran it through my good test cab - sealed back 2x12 loaded with a Vintage 30 and GH12. Miced it with a Zoom H1, set the controls at noon, bright off, mid boost engaged and r/j switch set for rock. Also, the OD trimmer on the back is set to noon (see pics).

First track was recorded as the amp sat. NFB resistor = 4k7. Looper in (sorry for the noise, this is native to the looper attached to the same plug as the amp).

Second track is the same setup control-wise. I used a decade box between tracks to adjust the NFB resistor. My logical side said to stop at 8k2. Anything lower than that starts to sound like a wet blanket being applied.

https://soundcloud.com/anthony-dorris-2 ... ild-tweaks

Keep in mind, this is from a looper. There is a click at the beginning of each track where the looper is engaged. There is another couple of clicks a few seconds in where Shane is changing pups. The second track has a couple of overloaded spots but I kept it as is for the sake of preserving the differences. Shane sent this looper sample along with the amp to be used for testing. Please give a listen, take a look and tell me what you think. Do you hear "violin-like"? Need me to change some settings and run it back? I'll do it... the amp is here waiting.

[dorrisant]

I don't know what to focus on vor violin-like tone... I sort of hear it trying to take off and sing, but it is in random places on the fretboard, so to speak, as opposed to a previous build that would sing for you anywhere, anytime. Took me a few years to stumble into the right combination of things to get it to do that. Quite a few differences between this D50 and the #124 circuit. So I am at a loss as to what to change next.

I'm beginning to wonder what a Bassman (50w) OT would do for it. I mean, its only a few wires to lift and I can clip lead it in.

Any thoughts?

[Shanedawg]

Hi Tony, I be up for trying a few more things being that you have it. Last 2 weeks have been shit. Wife decided to try and kill herself … I’m telling you thins because I’d like something that sings when I get it back.

[dorrisant]

Dude, that is harsh. Sorry you are going such a rough patch. Positive vibes headed your way.

As far as singing quality in this amp... I am leaning towards trying another OT. I know I have a working good pull from a Bassman, at least Silverface vintage, that I can clip lead in and try out. I will try this later today, clips for before and after. At least eliminate this from the equation.

[dorrisant]

So I tried a Schumacher 022889 OT. I thought it sounded a bit better, maybe placebo. The laminate stack is about 1/4" fatter on the old iron. A few people who played it couldn't tell the difference. I didn't tell them what to listen for. I did however get some good results out of tube rolling. I put a pair of Phillips (Mullard) 12AX7s in V1 & V2. I thought it made a big difference.

Here is the latest clip. Setting are different (pic below). I had never really tried dialing in violin-like tone specifically, so let me know what you think. I had always been under the impression that it would present itself when the OD drive is low and the level is high. Not what I settled on. Suggestions are welcome.

https://soundcloud.com/anthony-dorris-2 ... b1d884c7a8

It sounds grittier through the Zoom than it does with ears on the cabinet. Keep in mind that the amp is much livelier with guitar plugged straight in. The notes are sustaining very nicely, even full chords ring clearer and a lot longer than before I started. I need to get a real player back in here and let them rip.I haven't played enough guitar in the last few years, it been all about that bass.

[bepone]

i dont know what to say.. im always trying to be positive, there is a lot of effort to built one amp, more than hundreads of hours. but here to listen this i must to say it is somehow unpleasant and annnoying...it is a style of playing, short notes without sustain and "peaky". remaind me on some on my horrible amps 10 years ago with a lot of metal films inside and why i started to hate metal film

my recomendation, please remove this OD pot from the back side and return the trimmer on pcb or use only 2 resistors instead of trimmer
put cathode wires like dumble in layout, together not over everything, also your sockets are rotated little bit which changed the layout (better/worse?)
remove all those Ub+ wires from the sky and put them on bottom below, against the chassis
you have too much ungrouped wires laying randomly put this in order little bit
maybe something will change

[bepone]

I ran it through my good test cab - sealed back 2x12 loaded with a Vintage 30 and GH12.

i see now, two the worst and irritant speaker to my ears... it is impossible to have good sound here
do you have some normal speakers like celestion alnico blue, celestion gold or cream? EVM12L? minimum requirements - cheap but ok celestion V type? G12M / also ok / maybe?

[dorrisant]

I don't have much in the way of speakers and cabs. I actually have 3 2x12 cabs with the greenback/vintage 30 combo.

Also, this Zoom doesn't sound as good as other handhelds I've use. I have a Tascam DR I need to get back from a friend.

I also have SM57s and a half dozen or so room mics, but I'm in the middle of switching over/replacing some of the recording equipment, so it is kinda down at the moment. I have a Behringer 202HD and Cakewalk, but have no idea what I'm doing with them yet and it could be the middle of next year before I would say I'd have enough time be proficient at using that setup.

All that said, it sounds way better in person.

[dorrisant]

Also, the pot on the back is located there by VHT. I know that is not where HAD put it, but Dogears suggested to keep it there and change the values around it to what it is now. Not saying anyone is wrong, that is just where I got the idea.

[ijedouglas]

It's always really difficult to know what an amp sounds like just with clips (at least for me). Has Shane had a chance to play it and what does he think? I was also going to recommend trying a Marshall plexi-type OT but it looks like you clipped in a Schumacher and no noticeable difference was heard by others. If you heard an improvement, maybe try a plexi OT.

Is there something you are missing in what you are hearing or feeling from the amp?

[Reeltarded]

plug a guitar in and stop looping recorded things that do not react with changes

lol

[Guy77]

Hi Dorrisant. I was curious if this amp from VHT was built in a metal or aluminum chassis. I have heard others say that can also effect the tone.

Cheers

Guy

[Richard1001]

I don't think you can realy hear the amp when using a digital sample but what i notice:

The boards and sockets are dirty. Pieces of solder and other crap / flux. I would give it a good cleaning. And whats up with the 22pF snubbers? Try 250 - 360 pF