Tube Amp Archive

I have one of the xytronics irons (picked it up for about $50 at howard electronics supply or something like that, with whom I am not affiliated) and love it. It can do up to about 800 degrees, I think. The website sells all the tips as well. For the price, there is no way to beat it. I like it bett...

NickC, I am just north of Syracuse about 5 or 10 min. Nice to have someone in the area.

Thanks for the responses, guys. I checked and it turns out I had 470R mixer resistors as opposed to 470k (poor schematic resolution). That fixed the gain pots. The problem with the noise and such was that I didn't have any connection to ground for the unused channel (looks like the original used swi...

I have recently renewed my interest in amp building after a string of guitar builds and wanted to do a submini version of the plexi. I have it set up on my breadboard right now and it sounds great. However, there are two questions that I still have about this amp in general. 1) If I turn either inpu...

One thing I just tried last night that i quite like (in terms of using an unused ax7 side) is to do different input gain stages that can be switched to do one or the or both in parallel. I made an express preamp where I can switch the first gain stage between normal and a plexi or put them in parall...

The strange thing is that this used to work perfectly. It wasn't until about 6 months after I finished that this problem started. And sometimes, after playing for several minutes, it goes away. I know the caps aren't bad (at least they) and the resistors aren't bad. I tried a new tube when the probl...

After more than a year of moving several times and several thousand miles, I have settled back down to where I can do amp stuff again. I pulled out my first build that I finished some time ago, and the output was very low and very harsh/distorted/nasty. I traced the signal path with an audio probe a...

A relay is just a switch. The cool thing about them is that you can switch them on and off just by connecting or lifting the power ground. This makes it really useful for footpedal switching. A relay won't do anything that a normal switch won't.

I have used magazine paper before. I mostly have used it for smaller circuits, but I did the whole preamp/PI board using it on my first (and so far only) build. It gave me better results than PnP in most cases. Just make sure to get all your edges hot as well, as I find those traces to be the most s...

If you want it all passive, you could do a switched jack just before the PI. If you want a volume control that won't affect your preamp signal when you have no external source, you will have to have a separate box or something to adjust the volume prior the power amp in jack. I did this type of thin...

That could also make an awesome tube microphone transformer. Of course, building mics and building amps are different beasts.

I really like the projectguitar forum. I have built several guitars and the people there are very helpful. There is nothing like playing a guitar you built through pedals you built into an amp you built. Right now I do most of my playing through a neck-thru I built with active EMG's. I agree with th...

I don't own a strat, but have played several. The one thing that I dislike about most strats is the neck feel is all wrong for me. I played one strat that I liked and it was an American something-or-other. I have played a G&L I believe and didn't notice a huge difference tonally, though the playabil...

Why do I want to look at DC for the heaters? Well I am on my 3rd build. After hours of cleaning up the lead dress, rewiringing and resoldering all the solder joints, elevating the heaters, dividing voltages, and providing a virtual ground reference via qnty 2 100R resistors I AM UNABLE TO GET RID O...

I did DC heaters on my first (and only so far) build and it works great. I had to put about 3300uF worth of smoothing caps to make sure there was no hum, but with 5 gain stages, you have to be a little more careful. It was easy enough to do.