Line In (or Out?) & Headphone Out on a home-built amp

[XYZGnomon]

As I mentioned in an earlier post, I have never built an amp before so this question is coming from a position of ignorance. I have a lot to learn!

I will be building a Mojotone Brownface '63 Vibroverb 2x10, and since it's going to be a few weeks before I even get the parts I am thinking of all the things I want in an amp. Naturally, I want to modify it before I even have it in front of me!

First off, this will be a "practice" amp. I am neither gifted nor experienced enough to ever consider performing so this will probably never leave my house.

Does it make any sense to convert the normal channel into a line input on one jack and a headphone output on the other? Doing a quick search, I couldn't really find evidence of someone having done that before. I am aware that there are some expensive pieces of gear - like the OX - that do this, but that's more cables and power and whatnot that I would have to deal with, plus it's pretty expensive! Since I'm building this amp myself, it seems like a good thing to consider at the beginning if I could incorporate these features.

I think the tremolo is applied to both channels, so I assume that would complicate this concept - possibly to make it impractical or just not even worth considering.

If these questions have already been answered somewhere, I would be happy with a link as a reply.

[sluckey]

You have a HUGE challenge just to build the amp according to the schematic/layout. Get it working as is before even thinking about mods!

It's a real good idea to keep all messages about this vibroverb in one thread.

[pdf64]

Each to their own, but it seems topsy turvy to build a very loud, heavy, non master stage amp if you want a practice amp to use at home?

[acheld]

Both Sluckey and PDF are absolutely correct.

That said, a Vibroverb is one helluv an amp, and no one can fault you for wanting to build one. 

It would indeed be desirable to be able to plug headphones into an amp so that you can practice in peace.  It's not that easy to do.

My suggestion is to evaluate your needs and desires, and then build the best amp for you.   

But, build it stock with no mods and get it working first -- it will be a challenge -- and only then start thinking about modding it.

[Stuff4bikes]

I am a nobody rookie myself.......

Just a little advice.....start with something  a little more simple, single ended would be a good start......
Everyone is different but adding that PI and second output tube is not as simple as it may seem.
Get your feet wet on a fender champ, add a tone knob for excitement, excellent practice amp also.

[XYZGnomon]

Each to their own, but it seems topsy turvy to build a very loud, heavy, non master stage amp if you want a practice amp to use at home?

Sure is!

[XYZGnomon]

Both Sluckey and PDF are absolutely correct.

That said, a Vibroverb is one helluv an amp, and no one can fault you for wanting to build one. 

It would indeed be desirable to be able to plug headphones into an amp so that you can practice in peace.  It's not that easy to do.

My suggestion is to evaluate your needs and desires, and then build the best amp for you.   

But, build it stock with no mods and get it working first -- it will be a challenge -- and only then start thinking about modding it.

I agree that is probably the right way to go about it, and exactly what I will do. I'm planning on referring to this thread later on down the road when I inevitably want to tear into it.

I came to this forum because Hoffman seems like exactly the kind of company that would enable such a thing, and I would bet you guys probably know what you're doing around here.

[XYZGnomon]

I am a nobody rookie myself.......

Just a little advice.....start with something  a little more simple, single ended would be a good start......
Everyone is different but adding that PI and second output tube is not as simple as it may seem.
Get your feet wet on a fender champ, add a tone knob for excitement, excellent practice amp also.

I almost certainly would have done that, except for the Vibroverb is the only amp kit on the entire internet I could find that had a solid ship date and wasn't price gouged. Can you link to an amp that you think would be a better first-time-go option, that's in stock somewhere and can ship to Los Angeles?

[XYZGnomon]

I should mention that while I am not an electronics wiz, I am a CNC machinist and somewhat technically oriented. Until recently I worked on Starship at SpaceX and I'm about to start a new job making F1 engines. I come from a long line of nerds.

I am originally from Binghamton, NY, home of https://www.mcintoshlabs.com/. Maybe you've heard of it? My grandfather always had a half dozen tube amps in various states of disassembly all over his house, and his friends were all radio repairmen. I don't claim to learn by osmosis, but I think it was always inevitable that I would make a guitar amp someday. Did I mention I play guitar... poorly?

I totally agree that the '63 Vibroverb is probably not for beginners. I'm down for trying something more my size before I start on that amp, and some folks have suggested pedals. Some of the pedals I've seen the kits for don't seem less intricate than an amp... they just seem less lethal. The thing is... I don't really want a pedal, except maybe a tuner pedal. If you're reading this and you know of an amp kit available to ship that is better for a beginner, I am all ears and I totally respect that.

[Stuff4bikes]

I am a nobody rookie myself.......

Just a little advice.....start with something  a little more simple, single ended would be a good start......
Everyone is different but adding that PI and second output tube is not as simple as it may seem.
Get your feet wet on a fender champ, add a tone knob for excitement, excellent practice amp also.

I almost certainly would have done that, except for the Vibroverb is the only amp kit on the entire internet I could find that had a solid ship date and wasn't price gouged. Can you link to an amp that you think would be a better first-time-go option, that's in stock somewhere and can ship to Los Angeles?

I have never done a kit amp.....most of my builds are turret boards from this site and transformers I have from old radios, record players, reel to reels......I have used some new hammond transformers also. Buy a champ turret board, components of your liking
New or used some wire and caps/resistors and follow the instructions from this site and have fun.

[XYZGnomon]

I just ordered this: https://reverb.com/item/22720319-stewmac-57-mini-tweed-5w-amp-kit

I'll build this first! I appreciate the suggestions!

[Stuff4bikes]

That should work....

[ShoemanGB]

A tweed champ is a great first try. Did that myself.  I'm curious about the F1 engine job.  What manufacturer?  The technology in that sport is fascinating.

[d95err]

I would build the amp without mods and then get something like a Two Notes Torpedo Captor, to enable you to use headphones or line out to your stereo, computer or other device, for more silent playing.

[pdf64]

Personally I dislike tweed type builds / repairs / mods; everything seems cramped together and difficult to work on.
Hence I don’t recommend them as a first build.
A 60s black panel Champ or Vibrochamp may be a much more pleasant experience. The latter may even eliminate the point of building a Vibroverb.

[Keppy]

Some of the pedals I've seen the kits for don't seem less intricate than an amp... they just seem less lethal.

I recently built my first amp from a kit after years of building and designing pedals from scratch. Since I've built many pedals that are far more complicated than a tube amp, I underestimated the amp project.


The reason is that with pedals, I always etch a PCB, which cuts down on wiring. For amps, it's endless wiring. Stripping, forming, cutting... and each operation is a chance to make a mistake. I went SLOOOOOOOW. Stared at the wiring pictures a lot. It took me 6 days to finish, using all of my free time. No pedal ever took me that long to build.


And I didn't even run into any lead dress issues, which seem to trip up a lot of people. Lead dress rarely matters with pedals.


Given the same complexity of circuit, amps are much harder IMO.