Rickenbacker B16A Supersonic amp info needed

[Tomm Williams]

Tonight I bit on a fully functioning/serviced B16A chassis, another one of those "too well priced to pass on" amps. This was apparently pulled from a 4-10 combo made around '64. I'm leaning towards restoring it to original but can't even find a photo. Does anyone know anything about these amps? This is the tremolo model which is apparently a little different from the standard B16.

[DeepEnd]

Where do you come up with these things anyway? Here's an expired Reverb.com listing of the combo version with plenty of pics: https://reverb.com/item/140965-rickenbacker-supersonic-b-16a-4x10-combo-amplifier-silver. No clue what the specs might be.

[Tomm Williams]

Thanks for the link, now I have an idea what it should look like. This was just another one of those "blind luck" finds not even looking for one.

[WRGKMC]

Be careful on your speaker impedance. It looks like the speakers are in parallel on that amp. If its got a Transformer like a fender it runs at 2 ohms with 4 x 8 ohms speakers in parallel. It may have a different transformer and uses 4X16 to give you 4 ohms or 4X32 ohm to give you 8 ohms. Check the number on the output transformer to be sure before you go connecting to some cab. I ran a super reverb I used to own on an 8 ohms cab for awhile and the tubes wound up getting weak and distorted in no time.

[Tomm Williams]

The seller informed me it has was pulled from a 4-10 combo with 8 and 16 ohm inputs. The fact that it has two different inputs makes me wonder if this wasn't actually a head unit which I've discovered were in fact made. I wouldn't expect to find separate inputs on a combo but I really don't know. Turning it back into a head might be a cool option.

[WRGKMC]

Fenders had two speaker jacks even though they were combos. You can see here where the internal speakers use the one jack.

 

You'd have to disconnect the internal speakers if you used external cabs because anything in parallel would drive the impedance down below two ohms and short the power transformer below its minimum.

 

If you know your head is 8 or 16 ohms then you could use 4 X 8 ohms speakers wired in series parallel to get eight, but that picture shows all the speakers in parallel, so I'd confirm what the transformer impedance actually is and not take someone else's word for it (unless its actually printed on the chassis and then its likely a safe bet)

 

 

[DeepEnd]

Yeah, it's not that uncommon to find speaker jacks on combos. One is normally for whatever the impedance of the internal speakers is and the other is for some other common impedance, say 4 Ohms and 8 Ohms. You'd unplug the internal speakers and plug the external cab into whichever was appropriate. As WRGKMC said, your best bet is to find out for sure what impedance the amp is designed for.

[WRGKMC]

There should be a number stamped or tag on the output transformer. We should be able to google that and know what's in there.

 

I'm hoping its the same as most amps. No way of telling however. This amp may have two different impedance outputs because it has separate coil taps, it may also use some switched jacks in the back that disconnect the internal combo speakers when you plug in, or it may not.

 

Rickenbacker amps are fairly rare. Not many have survived the years either. I have a pawn shop over my way that was selling a solid state head. I was going to buy it just because it was so unique. I come to find out it was non functional and it had some transistors removed by a tech were sitting inside.

 

My guess is the tech did some troubleshooting and couldn't find generic replacements, or maybe they were unreadable and he couldn't find a schematic. I'd probably be able to repair it because the circuits looked pretty simple, but given the price they wanted for it I decided not to take on a load of spaghetti getting stuck like that tech did.

 

This is where buying vintage gear can really kill you. When you buy something discontinued it may be the parts for that unit were unique and have been discontinued as well. You may find good generic parts and other times you may design a work around that will hold up. I used to do allot of amp and Hi Fi repair when I first started out. I cant count the times I'd have someone bring in an Old Dynaco, Fischer Grunding where the companies have either been bought out or gone out of business and none of the parts manufacturers even make those old parts and you'd use some creative tricks to get things percolating again. I actually built a good rep by being able to tackle jobs no one else would touch because they were either unprofitable or they just didn't understand how some of the stuff worked. Age eventually does catch up with all gear because nothing man made lasts forever.

 

Your amp does look like it has a common build however. I'd think you could get just about any parts you need for it. Some chassis shots go a long way. If I were to see the parts inside I could tell you what its closest too. All these amp manufactures pulled their designs from the old Military radio handbooks then threw in their mods. Few hired engineers who could reinvent the wheels and the designs that strayed too far form the beaten using specialized or oddball parts wound up being unrepairable after they were discontinued.

 

I would take a good look at the power caps and check and make sure they are less then 10 years old. New caps may not even last that long, but they are inexpensive. Having clean DC power is the key to having great tone. Coupling caps are a big deal on an amp that age too. They are what connect the gain stages and as they get old that stop passing a signal so your amp drops in gain and frequency response. Replacing the coupling caps with orange drops and new power caps and tubes you might have a kick ass amp there.

[Tomm Williams]

According to the seller, this amp was recently serviced at a shop back east. As he received it, the OT was replaced as the original had blown. Apparently this was not uncommon in these amps ? ( or so I've read). I contacted another source who has one of these amps. He informed me the separate inputs are original as I think you guys guessed. UPS is delivering it within the next few hours so I'm looking forward to firing it up.

I believe I'm going to turn it into a 2-10 combo with Ragin Cajuns. Jeff Earl at J Design Cabs lives about an hour away and gave me a very reasonable quote.

 

Here are a couple of the pics the seller posted, price was sub-$300 delivered.

 

[onelife]

I'm hoping its the same as most amps. No way of telling however. This amp may have two different impedance outputs because it has separate coil taps' date=' it may also use some switched jacks in the back that disconnect the internal combo speakers when you plug in, or it may not...[/quote']

 

[WRGKMC]

That explains it then. You had me scratching my head there for awhile. The transformer was changed out so they likely used a Fender or Hammond transformer as a replacement which has 4~8 ohms instead of the stock transformer that was either 2 ohms or had higher impedance speaker to bring it up to 4 or 8 ohms. Few amps use 16 or 32 ohms speaker in parallel to give you 8 ohms.

 

The one large blue cap on the far left is new as are the smaller black ones. The rest are original 60's stock caps. You only change those as needed.

 

Cant read the values but this does look allot like a Fender circuit. Its even got the dual cap there. My Bassman has one I just replaced not long ago on my last maintenance. I'd be surprised if this amp didn't sound allot like a Fender. Both manufacturers specialized in making single coil pickup guitars and their amps were likely built to make those guitars sound good. Rics have pickups that sound closer to a warm P90 then a Strat or tele. The amp may have a little more treble/mid boost then a Fender but I'm only guessing here. You'll have to let us know.

 

 

There are two of those large caps standing next to the power transformer and over on the right in the first photo. Those aluminum jobs may be stock and very old or NOS. Replacements usually have the plastic coating on the outsides. If you get any hum at all, I'd target those for replacement immediately. They should only cost about $10 each and because this amp uses single caps instead of pairs like Fenders which provided some backup protection when one gets weak.

 

 

Otherwise that's a good looking amp.

 

I see it being just as good as any Fender would be from the build. I'd likely get 4 X 25W alnico speakers for it instead of higher wattage ceramics. The Alnicos would probably give it amp a tight clean jangle and the kind of string touch you'd expect to hear from a Rickenbacker. I bought 4 X 10" Jensen Alnicos for my Fender Bassman and what a difference it made over ceramics. Less mud and more touch to the strings.

[Tomm Williams]

I did see a pair of 64 10" Jensens for sale

 

Hmmmm

[DeepEnd]

I did see a pair of 64 10" Jensens for sale

 

Hmmmm

Nothing wrong with Ragin Cajuns--I'm a big Eminence fan--but a vintage amp really ought to have appropriate speakers. Those Jensens should do the trick nicely.

[Tomm Williams]

Only thing making me wonder is I already have vintage Jensens in about 7-8 amps. Maybe time for something else ?

[WRGKMC]

Oh well then,

 

At least you can use them to try it out then decide from there. Speaker choice as to be made when you know the range of the amps tone stack and its breakup gain levels. You can use those Jensens and secede if you need something with more bass, treble or mids so you can run thoe EQ's at 50% and get great tones. If you find you're having to max the EQ settings out at one extreme or the other you know either the speakers or the cab is a poor match.

 

 

Trying to think of some other choices without having actually heard the amp. The first thing that pops in my mind are Fane speakers, the ones they used in Music Man 4X10 cabs. Music man is another amp that sounds close to Fenders (Leo built the company) The Fanes in those 4X10 combos were killer sounding for blues tones. Johnny Winter used them in his Music Man amps and got some excellent Blues/Rock tones out of them.

 

I think they are actually making Reissues of those amps again but thay have some specially designed Neo speakers so I have no idea how thy would sound.

[Tomm Williams]

OK just got done giving it a quick plug-n-play and here's my first thoughts. I plugged it into the 12" from my Supro 1624 via 1/4" cable and a F-F adaptor, strikes me as very Fender/Vox-ish and highly touch sensitive. I didn't play it much as I didn't have a really stable place to position it so my test run was pretty quick. I pulled and inspected the pre tubes and found a Sylvania 12au7 along with 3- 12ax7's and one marked "7025 USA". The markings were largely gone on the ax7's but one said "Tungram Valve ecc83", two others had fewer marking but clearly said "Made In West Germany" on the lower portion. They also appeared to have said "The.....(something?) across the middle. Regardless, from the condition of the pins, they all appear well into the vintage realm. The 6L6's were GT's which I'm not a real fan of so I'll do some shopping later. The tremolo was a real treat, it sounded quite different from what I'm used to. Can't really describe it but it was cool. Yeah I'm thinking it might be sacrilegious to put anything but some vintage Jensens in here since that's what it came with. Perhaps the best $280 I've ever spent.

 

UPDATE..............the 7025 appears to be an RCA from what I'm finding out. It was in the V1. Found a pair of mid-60's Jensen C10Q's for a reasonable price so we'll see how it turns out !!

[Tomm Williams]

I might have stumbled across some info on the W.German tubes. According to one source, Telefunken 12ax7's were rebranded with the name " The Fisher". The word " The" is clearly legible as well as the " Made in West Germany". I think it's a safe bet this amp came with some pretty cool tubes.

[WRGKMC]

Yea, those tubes were pretty common back in the day. Telefunken were essentially Hi Fi tubes and not as durable as others. They can sound really good in a guitar amp for awhile, but they do tend to become microphonic in a combo because of the high vibration levels.

 

You can still buy NOS JAN 12AU7 Sylvania here https://www.tubedepot.com/products/jan-5963-12au7wa They aren't used in amps as often as the 12AX7 preamp or 12AT7's usually used for Inverters. The 12AU7 is a low output tube so whatever its driving needs a cleaner signal. Maybe its a tube used for that Vibrato you spoke of. It may also have been a substitute for a 12AT7 inverter. Unless you have a tube chart its hard to know what was originally in the amp. These tubes can be swapped as well as the 5751 which many players used for cutting down gain.

 

I'd be curious to know what they use for a rectifier. I didn't see a solid state rectifier bridge in the pictures and you didn't mention any 5AR, 5U4, 6CA4 tubes normally used as a diode so I can only assume the amp uses solid state diodes that were hard to see in the pics.

 

Too bad you cant find some Jensen P10R's for it. I bought mine for $50 each maybe 6 years ago but they've gone up in price since. The alnicos really add that extra touch tone you cant get from Ceramics, especially when you crank them up.

 

[Tomm Williams]

After having bought the C10qs (which is the original model this amp came with) and intending to build a 2-10", I started mulling the idea of turning it back into a 4-10 like it was. Of course it won't be an original cab but I think J Design Cabs could get real close. Given what seems to be the scarcity of these amps, I'm starting to think restoring it to near-original would be a worthy endeavor. Should I do that,I might consider a pair of those P10's to go with the C10's.

[Tomm Williams]

Any opinion on the P10R reissue ?

[onelife]

According to the schematic, posted earlier in this thread, the 12AU7 is used as the phase inverter and the rectifier is a 5AR4.

[onelife]

I put one in a SF Princeton Reverb and it changed from being a practice amp to a gig worthy tone machine.

 

There are some comments on this site that make the comparison…

https://www.jensentone.com/vintage_alnico/p10r

[Tomm Williams]

It must be my lucky day!!

 

I just found a guy with one of the original 4-10 extention cabs. It's empty but complete otherwise with all handles, corners, Ric name plate, everything. $250

I guess I'll be turning the amp back into a head to match the cab.

[WRGKMC]

Wow, that is a rare find. That makes about $500 plus your speakers.

 

If you already have two Ceramics coming, I'd likely stick with using two more of the same type instead of mixing and matching.

 

Sometimes mixes work and sometimes they don't. I have maybe 16 tens around the house in various cabs. I did allot of swapping around on my second 4X10 cab to get the best matches out of the bunch and I'm still not super happy with the sound. I'd have one set with a higher SPL so the second set wasn't as loud, I'd have other issues with abnormal peak resonances where the two sets had similar outputs at one frequency and at other frequencies you get a dip.

 

Like I said, I do have both types of Jensens. I think the Alnicos might over power the ceramics a bit at lower volumes and the ceramics will wind up pushing more clean bass at higher volumes.

 

With matching speakers your tone wont change much as you ramp your volume up. Even having another brand of ceramics with a similar SPL wont be so bed, but Ceramic and Alnico ramp up differently in volume. This might cause some oddball tonal changes depending on where you have the volume set. It may wind up being good. You just don't have a way of knowing unless you just try it.

 

If it works you're OK. If it doesn't then you're stuck with two sets that don't match and need to get a third so you have a quad.

[Tomm Williams]

Although this project seems to be falling in place pretty easily, I really don't know what the ceiling for ROI would be here. Maybe that doesn't really apply when the items in question are somewhat rare as these are.