Monkbam Pro Audio Marketing Blog

This has little to do with pro audio marketing or design, but it does have a lot to do with better sound. I have always liked taking things apart and perhaps my favorite things to take apart are guitar amps. I fell in love with their relative simplicity after I had built two SSL G4000 compressors from Jakob’s Gyraf plans. These things aren’t even that bad, but it’s that bad when you have never really soldered anything successfully before. Building these compressors was a challenge that taught me a lot about the different components and what they did, and how to troubleshoot.

I went to taking apart microphones after this and successfully fixed a bunch of problems with an old SM2 I had, replaced some bad components in a couple of Schoeps 221bs, and fuddled around with the headbasket on a U87 when the locking tab was missing on the body and I rotated the head enough to snap a wire going to the capsule. So, it all worked out after a few beers on the kitchen table and patience.

When a friend brought his Fender Bassman 135 over to the studio and asked if I could fix it, I had never even seen the inside of one of these. The Bassman 135 was built in the 70’s and had the linear transformers that reduced distortion, among other things. It was not a loved model for a while, but people are starting to pay more for them now that they’re getting older and the stigma has given ground to vintagicity. Forget for a moment that this word I made up sounds and looks like some contagious disease only girls would get.

After opening up the amp, there was all this room and the components were HUGE! I really couldn’t help admiring how much room there was to work, kind of like looking under the hood of an old Land Rover compared to a Saab 9000. You could do things without moving 30 other components. It was cool, and the beginning of my appreciation for guitar amps.

I fixed the 135 and bought a Super Sonic shotly after. This is a new Fender amp, but it sounded good to my ears at the time. I played a couple years with this amp and still have it for live shows, but here’s what happened in the meantime: I bought a decrepit 1966 Fender Bassman head and it changed my life…sort of. I had always wanted one since I walked into a guitar store at 10 with my dad and he said, “I used to play through one of those.” I didn’t understand at the time that what Fender puts out now with all of the vintage copy models  is not at all equal to what the vintage models actually were. Even the multi-thousand dollar models that are billed as “clones” are not anything like the originals. People who pay those prices simply haven’t heard an original, as much as I hate to be joining this group of vintage nuts. It’s the same for microphones—new stuff is useful, but it does not have the sound. So what makes sound, and why is old stuff generally better?

Well, not all old is better. The well made old stuff is generally better than the well made new stuff and only recently (in the mic world at least) have people reverse engineered the old stuff enough to come close to the sound. That also means a $6K mic from Wunder Audio, so you pay for what you get. But, back to guitar amps for a moment. For guitar amps, the transformers were wound differently and the coupling capacitors were made differently and had mojo. Of course, there are many other differences too that a tech nut will point out, like the voltages are different in different circuits at different stages, less feedback was introduced into the output, and so on. I’m not here to get too nutty, but I would welcome comments from those that can get too nutty, because I’m interested in learning. I’m talking about listening to specifically coupling capacitors and which ones don’t sound like crap.

A list, then, from Best to Worst and why:

1) The Fender Blue ones (or Astrons/Spragues) that were found in the late 50’s to mid 60’s amps. They sound the best and I’ve replaced the entire circuit of that Bassman five times over with different brands when I was restoring it and there’s no comparison. Using these in the “new” 5E3 Deluxe I have that was handmade by a cool dude, the Blue caps just completely gave the high end a smooth finish and took away the gloss and shrillness that was there before. In the Bassman, it sounds full and the soundstage is bigger. The sound has a nice roundness to it, but not too bell-like and bright when it had the Orange Drops.

2) Jupiter Vintage style film/foil caps. These are new manufacture and I’m awaiting a shipment of them now. The reviews are great, comparing them to the old Fender Blues, so the first project I’ll try them on is a Fender 5f6a Bassman that was rebuilt from the 90’s reissue model back to the original 50’s circuit. It currently has some Mallorys in it, so I suspect the difference will be quite big.

UPDATE: Got them last night and put them in the Deluxe. It sounds good, and I’ll be doing some testing soon. They seem to sound as full as the old Blues, and there’s no question that they are definitely in the same ballpark. I’ll be writing a fuller review of the caps and company soon, hopefully. The full review coming as a new post, because these things are THAT good.

3) The Orange Drops (715P or 716P) Polypropylene. These aren’t bad for new capacitors, but they have a big low end and a bright high end. The midrange is slightly subdued. They can have a little too much on the top end and perhaps this is due to the scooped mids, kind of like a lot of R&B records. When I replaced the Orange Drops in the Deluxe with the Fender Blue caps, the difference was incredible. It went from a bit brash and spanky to the smooth grind I want from a Deluxe when I plug my Tele in.

4) The Mallory 150 series. These are made in a similar way to the Fender Blues in that they are foil wrapped, but they sound far away from what the original Fender ones sound like. These are known for their midrange and while they may be a good compliment to the Orange Drops within a circuit, I have come to hate these. I replaced the caps in my Super Sonic with the 150s and while the tone is okay and more detailed in the midrange, I can’t deal with the upper mids emphasis that these caps have. So, those will be changed sooner than later. I’ve got a bunch of these—who wants ‘em?

So, who else has opinions on good caps for guitar amps? I’d love to hear opinions on what you’ve tried and your comments on the differences in sound. It’s all subjective for the most part, except the stuff that is pretty darn obvious.