I love old tube amps. If you dig them as much as I do, this blog is for you. Guitar, Hi Fi, recording gear, nothing beats the warmth and character of this antiquated technology. Shared here are tips to keep your much loved old amps in good shape, and tips how to improve your new gear. Have a comment or suggestion? Leave it here! Thanks for reading!
Hi all. About 2 weeks ago my favorite little amp was stolen from me. The photos here are from about 5 years ago and it's more beat up now. I also replaced the knobs and the pilot light which it sky blue, smooth glass.
Any info would be much appreciated. I've filed a report with the NYPD......
This amp was gifted to me by a dear friend in Vermont. I just got it running tonight. It's a somewhat rare PANaramic amp built by Magnatone.
These are the "after" photos. I changed the badly stained grill cloth.... Before:
Gross!
This poor amp sat unused for probably more than 2 decades. It was a part of Indigo Studios vast collection of 400 amps. When it came to me it was DOA. Bad power transformer. So I figured I'd replace it and change the filter cap as well, ground it yadda yadda. The usual.
The part I used was from Triode Electronics, their Classic Tone line:
My concerns were: I don't feel like drilling any holes. Actually, that was my only concern. I just wanted an easy fix today. The original part, dated 1962, has all wires on one end with the end bell right up against the chassis. Fortunately the replacement part gives you plenty of room to run the wires on the other side of the transformer across and put it all through the chassis hole.
What we are replacing:
On the chassis, Magnatone generously gives you these nice, long, oval holes to fit many sizes of transformers, Good for me as the part I ordered was a bit too big.
With parts installed:
With the bigger transformer I get a B+ of 417VDC, perfect. I imagine the original is less, please correct me if you know. The replacement part is the same as a Deluxe Reverb only with upright bells. My main amp is modeled after a Tweed Deluxe and I use the Deluxe Reverb part for extra juice. I've used that amp for a decade now and haven't had any issues. Good tubes last a long, long time.
In this particular amp I was happy to find it was loaded with Telefunken 12AX7 tubes, the smooth plate variety. There was a missing 12AU7 vibrato oscillator which I replaced with a nice RCA. The power tubes were Sylvania, still good, and I dropped in a Westinghouse 5V4 for the rectifier.
I used a C.E. Manufacturing 525V Quad Cap for the can. Makes for a tidy job and worth the expense.
It still retains the original Oxford speaker:
Still good! No need to replace or re-cone.
Other shots:
I know very little about the PANaramic line. These were built to match Robert Pancottis' PanCordian. Yes, it's an amp for the accordian, once an immensely popular instrument like the Hawaiian lap steel. It's similar to their Troubadour model 213 but with a different preamp layout and an odd "stereo" input. It's a mono amp folks, one speaker, one phase inverter, one transformer.
Here's a bit about Magnatone and their wild market:
So how does it sound? I ain't gonna lie. I have a thing for Magnatone amps. You can buy one of these for about a grand, sometimes a bit more, sometimes less. It's still a lot of amp for your money. I would gladly pay that much for one. It's lush yet very clear and that true pitch vibrato? Better than Fenders lovely Brown panel era, better than Vox and their true pitch vibrato as well, which is also quite lovely. It's the sound of Bo Diddley, Johnny Cash's guitar sound on "Walk the Line". I believe Magnatone was the first to get this sound. Straight it's just a great tube amp. More 'creamy' than 'crunchy'. More refined I would say.
I don't know yet if it's a keeper, I have a small place and too many amps right now! I don't like things to compete with each other. But if you read my post about the Magantone A-646, that's the best sounding amp I own. So now that's a keeper. Tracked with it all weekend using a Les Paul. Heaven! Better than a tweed Fender that amp is.
Here's a bit of my roommate playing his electric oud through my PANaramic:
And Bo Diddley in my favorite track:
Johnny Cash:
These are beautiful sounding amps. I also like the fact that all the tubes are quite common and easily sourced. The bigger Magnatone amps are a chore to restore though well worth it. These cute little ones for me, they are where it's at. Cute and compact and easy to enjoy.
Just finished this one, a very rare Magnatone A-646 amp from about 1951. This one us a real gem and is visually striking as well.
I bought this amp by mistake on Reverb this winter. I put an offer on a Varsity that I wanted as a backup to my main one and the owner declined. It wasn't a bad price and I love those early Varsity amps and it was pretty enough that I was willing to pay his price anyway. This one came up in my feed and I was curious so I put an offer on it. The owner said he would think about it. First amp wound up coming through at my price so I bought it then.......so did this one!
This one arrived first. It was noisy, had some really poor tech work done to it so I got it going. I wasn't all that impressed with it though and even after re-capping the power supply it had a considerable amount of hum. I even added another filter stage. I knew there were other solutions, maybe filament, maybe ground loop but I shelved it. If it's mine I tend to just put it away and forget about it.
So today I did a better re-cap, with a nice expensive C.E. can, an additional filter stage and while it got better and was certainly tidier, still hummed at an unacceptable level. So I disconnected the center tap of the 6.3v filament and added a hum balance: 2x 100 ohm resistors, one on each side of the filament, the other sides both going to the cathode bias resistor on the 6V6 tube. Looks like this:
When I brought this up on my Variac I thought "dammit! I killed my amp! Time for more troubleshooting!" I just wanted to be done with it. But reality is, the amp is just so quiet now! Hum free with only a little bit of noise when it's turned all the way up.
This amp I believe is the precursor to the Varsity Deluxe I reviewed here. Similar circuit, 40's style box, single 6V6 and 5Y3 but driven by the darker more euphonic 6SL7 tube rather than the snappier 12Ax7. It has a single 8" Alnico 5 Jensen speaker.
More pics:
How does it sound? Like the early version of the Tweed Fender Princeton. It's a similar circuit, but this plays cleaner and more articulate. It has a big sound for such a small box, warm but not fuzzy. Ideal Wes Montgomery or Charlie Christian sound. I'm a big fan of the Magnatone amplifier, especially the early ones. They are a bargain. I may sell this one but not for cheap! I like it a little too much.
The only drawback is the 6SL7 tube can be microphonic. If you turn both the volume and tone all the way up it may sing a song. The 12AX7 is a better tube for guitar amps. You could simply use a 6SL7 to 12AX7 adapter available on EBay, or you can just roll a little bit of the tone control back and enjoy that big warm sound.
If you like something different, give one of these a try! They are lovely little amps!
JB
8/29. After tracking with a Les Paul all weekend I've decided this is my best sounding amp. Bigger tone than a tweed Champ, smoother top, goes to tape beautifully! It's a keeper! Do look out for one of these. I did some reading about the hum and one tech mentions he struggled with his as well. he resorted to installing a big ass choke and extra filter stage. That should do the trick but try the hum balance first along with adding one filter stage. Quite happy with the results here. JB
I love Magnatone amps. Just a great, warm sound all around. I've worked on dozens of Varsity amps, but not the Varsity Deluxe. Completely different circuit, more like an early tweed Princeton. I do own a Magnatone Model A646 that is similar to this amp circuit wise except it uses a 6SL7 rather than a 12AX7 for the preamp. This amp loses the Hawaiian theme, a move from the 40's to the 50's. Classic Jet Age style.
Typical single 6V6 tube with a 5Y3 rectifier and 12AX7 preamp. 5 watts, 8" speaker....
Grounded it, re-capped the power supply, fired it up for the first time in probably more than 2 decades (pulled from an old studio that had 100 amplifiers in various states of neglect 17 years ago!).
Sounded like crap.......
A little secret. The ceramic caps in these can sound terrible. Just change them. These amps aren't worth much so why have 'originality anxiety'? I replaced them with some Mallory 150 caps and the amp came to life. It sounds fantastic. Punchy, good volume, lots of warmth and harmonics. Great jazz tone with mild breakup. The earlier Varsity amps had great signal caps. If they are still working I leave them alone. The later ones use those lovely Ajax blue pill caps that Fender used. But these? Pure crap. Trash them and enjoy your amp! These can hold their own with any other small amp from the era. Transformers are excellent and the speaker is a nice little Jensen. Worth re-coning if it's fried.
Not much to say about this little amp, I believe it to be made in the 40's, probably before it was called "Varsity". These are one of my all time favorite recording and yes, performing amps. I have a later mother of red toilet seat ones. Just lovely sounding. Not super gainy tweed Champ nasty, just a good sweet overdrive.
This one arrived DOA. Belongs to my friends in 75 Dollar Bill: (click invisible link below!)
Probably about 4 watts max. They have the classic 3 tube setup: 5Y3 rectifier, 6V6 power tube and a nice 6SJ7 pentode for the preamp.
The problem? Just dead caps. This amp is close to 70 years old. Caps die. Tubes were all NOS, I sold them to the band a few months ago and now this little amp simply rips. Has a new Jensen alnico speaker with barely enough room in the cabinet for the tubes to fit! But it works so.... And it sounds great. Not usually a fan of those new Jensens but in a darker sounding amp like one of these, they work really well.
Go try one, maybe buy one! These are a bargain. Not a "Champ Killer" or anything like that, they have their own thing going on. Perfect bedroom amp!
