Unmasking Fender Silverface Amps - The Free Information Society (2)

7/30/2019 Unmasking Fender Silverface Amps - The Free Information Society (2)

http://slidepdf.com/reader/full/unmasking-fender-silverface-amps-the-free-information-society-2 1/10

Unmasking Fender Silverf ace Amps - The FreeInf ormation Society

by Frank Strou pe

***WAR NING -There are voltages inside of a tube g uitar amp that can KILL you . There are componen ts in theam p that hold live cu rrent long af ter the am plif ier is unplugged. If you are not f amiliar with workin g on vacuumtube equ ipment, you should con sult an ex perienced tech nician bef ore openin g any equipment contain ing vacuumtubes. T his article is f or inf ormational purposes only. T he Free Inf ormation Society will n ot be responsible f or anyin jury or dam age caused to you or your equipm ent.***

Early Silv erf ace Logo on Standard Silverf ace Grillcloth

So, you'v e heard all of your gu itar playing lif e, whether it be f or 2 years or 25, that you don't want a Silv erf aceFender amp.

I can't say today that th ey are the "best kept secret", because over th e past f ew years, the prices on them aresteadily clim bing...so obviou sly, the secret h as gotten ou t. That MusicMaster Bass am p or Silverf ace Cham p thatyou could have bou ght all day f or 50 bucks as recently as 2 years ago can run as h igh as 350-400 on ebay now.Though, hopef ully no one will bid on those that are th at high. Other silv erf ace am ps have similarly appreciated.But, they are still av ailable at killer prices, if f or no other reason, there are man y of them still available...m any asilverf aced am p was passed over in the 80's and 90's by som eone that HAD to hav e a tweed or blackf aced one.I recently purchased a 1972 Silverf ace Cham p f or 40 bu cks.

I am not an ex pert on am ps, Fender amps, or Silverf ace Fender am ps. Nor am I a tech . I am m erely someonethat loves old gear, appreciates Silv erf ace am ps, lov es to write, and loves h istory. So, here I am, writing aboutthe history of some old gear, the Silverf ace Fender. I also have a small am ount of knowledge of and experiencein working on tube am ps.

This is in tended to be an inf ormative article f or the uninf ormed, and is purposel y not terribly specif ic. I'm also notgoing to get too deeply into technical details of circuitry. I apologize in advance if I got a date wrong, a m odelwrong, etc. Its pretty hard to g et extremely accurate inf ormation on th e history of Fender amps...f or several

reasons...and someone will alway s criticize the specif ics.



I also apologize f or not hav ing a lot of photos of mint Silverf ace equi pment. Presently, I personall y own only twowell worn Silv erf ace road warriors, a 1971 Cham p, and a 1972 Bassm an 50 (AA371). Both had seen man ymiles by the time I got them, and I've added a f ew more to the Bassm an in the nearly 20 years th at I've own ed it.Actually, when I bought m y head, it was in a Blackf ace box ...which conf used me f or a long time until I realizedwhat had happened. I have a f ew other jpegs of other silverf ace equipment I know the owners of . I suppose Icould have ripped of f some photos f rom other websites, but th at's not my style. If you need to see th em, G ooglethe Fender Field Guide.

My 1972 Ch am p

What the heck is a Silver f ace?

Quite sim ply, a Silverf ace Fender Amp is an amplif ier made by the Fender Musical In struments Company f romlate 1967 to 1983. T hey are called " silverf ace" due to the brushed alum inum look of the f aceplate. Much moreon this later.

So, w hy don't I w ant one?

I suppose th at if you com pare Silverf ace equ ipment to its earlier tweed and blackf ace breth ren, the silverf aceam ps are in m any cases not that great, and that is the justif ication that has been used f or a couple of decades bySilverf ace critics. Do a quick look on ebay, elim inate the ridiculously high opening bids that no one else has bidon, (wh ich in case of the search I ju st did is well ov er half of them) and y ou'll f ind that in m ost cases you canex pect to pay about twice as m uch f or a Blackf ace than a Silverf ace, and at least three or f our times as much f ora tweed. (5 or 6 times as much in the case of a tweed Cham p vs a silverf ace one) Face it, tweeds are actuallymuseum artif acts, and if you f ind any genuine tweed Fen der f or under a grand, buy it and con sider yourself extremely lucky, and I'm not going to com pare Silverf ace equ ipment to tweed.

Personally, I would rather com pare Silverf ace equ ipment to wh at is available today. T ake the Silverf ace Cham p.It is a great sounding little am p, and y ou can u sually pick them up f or under $200. Where else are you going tof ind a tube rectif ied, sing le ended, h and wired, 6 watt (and a very strong 6 watt) am p f or $500, m uch less $200?Yes, silverf ace amps are hand wired. I have an Epiphon e Galaxie 10 that I was giv en f or Christmas. It is a 10



watt (maybe) sing le ended tube am p, with solid state rectif ier, prin ted circuit board (PCB), and cost $199...itisn't as bad as some PCB amps, because th e tu be sockets are attach ed to the steel chassis and not the boarditself . It is a pretty cool little amp, and I reall y liked it. Un til I A/B'd it again st my Cham p. I don't think it has been

plugged in since...th e Champ was lou der, and sound ed MUCH better. (I'm not knocking the Galaxie...I still think it is a great little amp, especially f or the price...I think that G ibson made a mistake discontinu ing it...it just n eededa little im provement)

I mentioned that the Ch amp is h and wired. Actually, it is pretty incredible, if you really thin k about it, that Fender was still hand wiring all of their tube am ps in 1982. For that matter, y ou can of ten pick up Bassman or Bandmaster heads f or under $300...where are you going to f ind a han d wired 50 watt head f or that? Where areyou gonna f ind one f or $1000?

And, silverf ace am ps are bu ilt like tanks. T he cases are heav y pine plank and/or marine plywood, withdovetailed corners, the transf ormers are hu ge, every thing is overkill.

1971 T win R everb

Som e background inf ormation

Leo Fender, who was in poor h ealth due to overwork, alon g with his partner, Don Randall, sold his beloved"Fender Electric Instru ment Company" to the Columbia Broad casting System (CBS) in late 1964, with CBStaking over in early 1965, and chan ging the name of the com pany to " Fender Mu sical Instrumen ts". Pretty muchf or the f irst 5 years, CBS d idn't make th at many changes to the am p circu its in production when they took over,and kept th e current cosm etic scheme, a black f aceplate with white lettering, black tolex (which Fender h adchanged to in 1964) and a bon e colored grillcloth with black and silver threads in it. But, there were a f ewchanges here an d there, some models were discontinu ed during that time...such as the Concert an d Pro in 1965and the Deluxe in 1966.

In late 1967, Fender chang ed the cosmetics of the f aceplate to a brush ed aluminum look with blue and black lettering, and the grillcloth was given a blue " sparkle". T here were a very f ew cosm etic changes m ade between1968 and 1980. For the n ext f ew years, many models received m ods to the current circuits, an d in some casestotally new circuits. Probably the big gest chan ge made by CBS was g oing f rom a true " bias pot" to a " balance

pot" on the class A/B am ps. A little more on that later.

(Unlike many others) I don 't prof ess to kn ow what CBS was doin g, why they went the direction they did withthe circuits. Most changes generally made a louder, cleaner sou nding am p, with m ore headroom. Of course,



during th is time, rock m usicians were seeking m ore and more distortion. Don Randall obviousl y didn 't agree withwhat was g oing on, as he resign ed his general man ager position in mid -1969.

Around 1970, th ere was a music store th at I wou ld stand in f ront of of ten, slobbering at th is silverf ace DualShowm an R everb with two cabs that they had in th e window. It just looked so massive. A f ew years later, whenI actually started playing the gu itar, th at am p was f orgotten ...my dream was of a Marshall f ull stack. By that time,no one was u sing Fender am ps, except f or Ted Nugent, and he was in a class by himself anyway. From

probably 1976 to the early '80's, I really don't even rem ember seeing a Fender am p in a music store, much lesson stage.

Between 1968 an d 1972, reverb and vibrato was added to several m odels, and master volume was added to af ew. By m id-1976, most Fender am ps 50 watts and over had a m aster volume. I guess it was a too little too lateattempt to draw some rock m usicians over. T hat Decem ber, the m ovie "Saturday Night Fev er" was released, the"disco" era began, and m ost musical instrument manuf acturers suf f ered to som e extent. Many closed their doorsin the late 1970's. Thou gh, I will say, during that time, I saw a f air number of DJ's using Fender colum n PAsystems, so they were selling at least some amps.

In 1980, Fen der went back to blackf ace cosmetics. The silverf ace models that continu ed throu gh this period arestill considered silverf ace amps, the new m odels in troduced throu gh this period are generally called "R ivera"Fender amps, an d begin a new era of Fender amps. By the end of 1983, all silverf ace am ps were discontinued.

Later Silverf ace Log o

Blackf ace vs. Silverf ace

So what's dif f erent between the am ps of the blackf ace era, and the silv erf ace era. As I h ave alread y mentioned, probably the most im portant change was goin g f rom a bias ad justment pot on th e blackf ace amps, to a pot thatallowed one to balance the bias between the two tubes...or pairs of tu bes on th e larger am ps. This was done tohelp elimin ate hum, m ostly f rom poor circuit d esign and sloppy manuf acturing processes. Probably the bigg estreason was to allow f or usin g pairs of unmatched tubes. By the late 1960s, th e quality of tubes f rom Am ericanmanuf acturers had dropped greatl y, mostly due to poor qu ality con trol. The balance pot com pensated f or that,thus eliminating the n eed f or going thru countless tubes to g et matched ones. T he problem with the balance pot isthat attempting to reset the bias af ter replacing tubes becam e a major undertaking.

Another change f or the silverf ace amps was that voltag es increased pretty m uch throu ghout the circu its. Not aterrible th ing in itself , but keepin g in mind that Fender was obviou sly looking to keep the amps clean, other changes had to be m ade in the circuits to com pensate...usuall in weird f eedback and negativ e f eedback



loops...wh ich took more of the beau ty f rom the tube tone.

And the above caused other problem s...a major on e being oscillation. To com pensate f or that, many circuits had"snubber capacitors" , small valu e capacitors ru n across the power tubes to f ilter ou t some high f requencies.Many people f eel that th ese kill the " sparkle" that was com mon to the blackf ace am ps.

And, there were other changes. Fend er got away f rom using Mallory capacitors to using "chocolate d rop"capacitors, which many f eel just don 't sound as good. By th e late '70's, th ey had chan ged to u sing ultralinear output transf ormers, which increased ou tput wattag e, but also increased voltages in other places in the am p.They started putting m aster volume pots on som e models in 1972, an y by the end of the decade, pretty much alllarger models had a m aster volu me, some with push-pull pots, " pull f or gain" . Also, Fender changed brands of speakers that they used over the years, ev en Leo did. By th e '70s, exceptin g the f ew models th at had JBLspeakers, CBS Fender used som e pretty crappy speakers. It is extremel y common to f ind silverf ace equipm entwith speakers that were replaced with non-stan dard ones 25 years ag o.

1976 Dual Showman Reverb

So how do they sound?

I can't sit here an d truth f ully say that silverf ace amps sound as good as blackf ace, though the 6 and 12 watters pretty much do. The bigger am ps don't sound bad, many of them just don't sou nd great, especially whencompared to their blackf ace ancestors, which I've already said cost twice as m uch. I have heard f or many years,"don't get the ones with master volu me", "don't g et the ones with u ltralinear" , "don't get this" , "don't getthat"....mostl y "don't get silverf ace". Most of these people with the warnin gs, when asked, actually had n ever

person ally owned a silv erf ace Fender. "I know better."

But, talk to som eone that has owned one...especially som eone that had heard all of the warnings bef orehand...as



of ten as not, they will tell you h ow surprised they were to discover how good a silverf ace really soun ds. I have person ally been told by more th an one person, that af ter swappin g the speakers, their large silv erf ace sou ndedgreat, an d they couldn't believ e that they bou ght all of the bad inf o they had been given over the years.

The small am ps have that tube tone, regardless of what you've heard. T hey all (if working correctly) pretty m uchare clean up to "5" or "6"...and everything af ter that is compression an d distortion. T he larger amps h ave a lot of clean headroom ...which is obviou sly what Fend er was shooting f or. If there is nothing in you r sound chain

between guitar and am p but a cord, and y ou like pure tube tone...y ou won't go wrong with an y of these am ps.

Later Model Mu sicMaster Bass Am p

The small amps

I guess th at the best tone f ound in silverf aced am ps are in th e small on es...bu t isn't that tru e f or most am ps? TheCham p, VibroCham p, Bron co, (6 watts) Prin ceton and Princeton Reverb (12 watts) retain ed tube rectif icationthroughout th e '70's. T here were a f ew small ch anges m ade in them, but both retain basically th e blackf ace circuitthroughout th e silverf ace era. T he MusicMaster Bass am p (12 watts) was introduced in 1970 as a 12 watt bass

practice amp. IMO, it is totally worthless as a bass am p, but is a little guitar tone monster. All th ree hav e a similartone, IMO, with the Champ sportin g the most distortion . Though both th e Princeton and the MMB are class A/B6V6 amps, they share very f ew other similarities in their circuitry. T he VibroCham p is the most desired of the

bunch, and usually f etches the most cash, but to be totally honest, I have nev er played th rough one, and I reallydon't rem ember hearin g anyone else doin g so...I'm personally not a big f an of vibrato/trem olo in am ps.

A little f urther up the ch ain, there is th e Deluxe Reverb (22 watts). The Deluxe, which probably is my mostf avorite Fend er am p, was discontinu ed in 1966, and the Delux e R everb replaced it. Other than sporting a pair of very "hot" 6v6's, there are f ew similarities in the two, th e DR just doesn't sound quite as g ood as th e origin alDeluxe, but close. Bu t, I promise you , it blows away the '65 Deluxe R eissue, or a Hot Rod Delux e.

The bigger am ps

Next we g et to the 35-70 watt am ps, wh ich included the Pro R everb, Super R everb, Vibrolux Reverb, wh ichwere all combo amps, and the Bandm aster and Bandmaster R everb h eads. All of these am ps sported twin6L6GC power tubes, and were rated between 35 an d 50 watts. (70 watts by 1976 af ter the circuits were

chan ed to ultralinear All of these am s had one thin in common ...the were LOUD...an d enerall clean . The



all had a master volu me added by the late '70's.

The main problem with all of these am ps is clean headroom . By th e time the 6L6GC's start giving som e decentcompression and distortion , you are pretty much at window sh aking levels. T hough, an y of them would beexcellent if you are u sing stom p boxes or ef f ects processor.

1972 T win R everb

The big boys

Armed with a qu ad of 6L6G Cs, the T win Reverb and Super Six com bos, and the Showm an 15, the Du alShowm an, and the Dual Showm an R everb h eads, were an d are capable of earth sh aking, ear bleedin g cleanvolume levels. They were rated at 85-100 watts, and the u ltralinear ones were at 135 watts. If you are lookingf or distortion f rom th ese babies, unless you are playing a hug e outdoor venue, your audience will def initely

ex perience some hearin g loss...an d if you don't use ear protection, you will too. T he later version s do hav e amaster volum e, and is capable of some distortion, but if you use pedals, there's no n eed f or it, turn it to " 10" andcontrol th e volume with the reg ular volume pots. A Dual Showman Reverb, coupled with a pair of cabinets, is anim pressive display in deed. Som e people pull a pair of tu bes to get a more m anageable volum e f rom them, butthey are still very loud.

The ridiculous and the sublime

For whatever reason, Fender built som e models with a complemen t of six 6L6GCs, th e Super T win R everb andSuper T win R everb combos, both rated at 185 watts. Why someone would wan t a 185 watt com bo, I have no

idea, except f or may be heating a small home in th e winter, and maybe doing a show on the f lightline of an airport.I have never personally heard either, but I im agine that th ere is zero distortion gained f rom these am ps.



My 1972 Bassm an AA371 with blackf ace grillcloth on head and non-standard grillcloth on 2x12 cab

The Bassman

The Fender Bassman am p was f irst introduced in 1952 as am plif ication f or Fender's newl y invented PrecisionBass. It went through several chan ges throug h the '50's, with various circuits an d speaker conf igurations. By theend of the decade, it sported 4-10" speakers, solid state rectif ication, and aroun d 50 watts, and open -backed

cabinets. T o later standards, all of these amps m ade f airly poor bass am plif iers, but keep in mind that the electric bass was replacing the u pright bass...which was very percussive, and did not hav e the " boomin g" bass sound thatcame later. Sometim e in the early 60's gu itar players decided th at the Bassm an made an excellent guitar am p.The f inal version of the "tweed Bassman ", the 5F6-A, became very desirable, and people beg an copying thecircuit with some slig ht modif ications, and marketing these as g uitar am ps, most notably Jim Marshall of MarshallAm plif ication.

In the early '60's, Fender wen t to a head/cab con f iguration , f irst with tube rectif ication and 1x12" speaker, thensolid state rectif ication and 2x12" . The Blackf ace Bassm an am ps had three circuits, the AA864, which m anyconsider the best post-tweed circuit f or use as a gu itar am p, the AA165, the last Bassman with an actual bias

pot, then th e AB165.

The AB165 circuit continued through out the Silverf ace era, receiving a master volu me and ultralinear outpu ttransf ormer in the later m odels. Oth er circuits are AA568, AC568, AA270, AA371, an d probably oth ers.Fender changed to a 2x15" cab in 1968, an d the speaker brands varied as m entioned above. JBL's were of f eredas an option f or most of the '70's...a very much desired cabinet.

In 1968, Fen der introduced the Super Bassm an, a 100 watt Bassman , later called th e Bassman 100. In 1972,the Bassm an 10 was introd uced, a 50 watt 4x10" com bo with master volu me...the circuit of the Bassman 10 wastotally dif f erent f rom any other of the 50 watt Bassm an models, an d f inally, in 1982, the last new Bassman in theSilverf ace era was added, though with Blackf ace cosm etics, the Bassman 20...an 18 watt 1x15 com bo, sportin g2 6V6 power tubes. Person ally, I h ave never seen one of these, bu t would love to try one.

I decided to put the Bassm an in a section by itself , because the dif f erent circu its are so conf using. In 1972, if youwalked into a store and bought a Bassman 50, y ou could have gotten any one of at least 5 totally dif f erentcircuits, m ost of them sounding somewhat dif f erent, y et all were called " Bassman 50". Most of the changes in thecircuits were dif f erent f eedback an d inverse f eedback loops, and changes in the ph ase inverter circuit, obviousl yto limit distortion f or a cleaner sound. Not a bad thing f or a bass am p, but not so great f or guitar.

So, how do you know wh ich circu it an amp is? T he Fender f actory was notoriou s f or just slapping the f irst



available tube chart in a head...and su pposedly it is extremely com mon f or the tube chart to be the wrong one.The only real way to tell is to actually look at the circu it and compare it to v arious Bassman schematics. ***Seethe warn ing above***

The Bassm an heads were m ostly overlooked by gu itarists throughout the 1970's, it just wasn't as v ersatile asmost of the other am ps out there. Even af ter a master volume was added, the Bassm an didn't h ave the cru nchydistortion desired by rockers. T hen comes along Stevie R ay Vaug hn. SRV was always in search f or the perf ect

tone. When he mentioned in a f ew interviews th at he used a Blackf ace Bassman head in his setu p, suddenl y theBassman head became popular with gu itarists. Of course, bein g much cleaner th an the Blackf ace, the Silverf aceBassman was much less desirable.

So, how do Silverf ace Bassm an amps sound ? With th e exception of the early AB165, they have ton s of cleanheadroom . My AA371 f inally starts getting some distortion at window vibrating levels, but it is a nice distortion.Of all of the Bassman 50 amps, it is su pposed to be the most clean. If you use pedals or processors, the inh erentcleanness is f ine...letting your ef f ects do th e work, ju st adding som e tu be warmth to the process. T he AB165distorts much earlier than the other m odels, and is by f ar the most desired of all of the circuits. Also, it is"blackf aced" easier than the other Silverf ace models.

Blackf acing Silver f ace Fender s

If you have shopped or researched Silverf ace am ps at all, y ou probably h ave come across th e term"blackf acing". Simply, blackf acing is modif ying to som e extent the circuits in a Silverf ace amp to the specs of those in a Blackf ace. It may involv e simply ch anging the values of capacitors and/or resistors, or actual chan gingof the circuit itself . The only true " blackf acing" involves scrapping the entire circuit and rewiring the amp to theAA 864 or AA165 circuits, in the case of Bassman am ps. Generally, there is very little blackf acing that can bedone to the later Silv erf ace am ps, those with ultralinear output transf ormers, the voltages are just too high . Shortof replacin g the OTs, anyway.

Be aware, that there are people out there selling amps claimed to have been blackf aced, that very little chan geshave been made to. G enerally , to blackf ace a Silverf ace am p, the bias circuit is rewired to a bias pot instead of a

balance pot, the phase inverter circuit is rewired, f eedback circuits are eliminated, an d inverse f eed back circuitsare changed to resem ble those of the Blackf ace am ps. Usually , there are extensive changes m ade to the circuit toaccom plish true blackf acing, in many cases, ev en changing f rom solid state rectif ication to tube rectif ication.

If you are truly in terested in blackf acing a Silv erf ace am p, a Google search will f ind you nu merous sites withinf ormation an d instructions on blackf acing.



In con clusion....

Having said all of the above, Silverf ace Fend er Am ps are actually all pieces of junk, and should be sent to m e f or proper disposal, to prevent harm to the environm ent. Please notif y me in care of The Free Inf ormation Society,and I will tell you where to send it...at you r ex pense, of course.

Excerpted f rom U nmasking F ender S ilver f ace Amps - T he F ree I n f ormation S ociet http://www.f reeinfosociety.com/article.php?id=275

R EADABILITY — An Arc90 Laboratory Experiment http://lab.arc90.com/experiments/readability

Documents

Unmasking Fender Silverface Amps - The Free Information Society (2)