Fender Twin Reverb Silverface 1969

Fender Silverface Twin Reverb
1969
Serial No. A20769

The Fender Twin Reverb is one of the most popular and desirable amp in the Fender tube amp line. It is re-issued by Fender and remains a current product in the Fender amp product line-up, attesting to its popularity. It has an awesome clean sound that is well-complimented by its built-in reverb and tremolo effects. It is pedal friendly and it is easy to get desired sounds using outboard effects.

I did a very rough comparison noodling through my '69 Twin Reverb and my '73 Fender Vibrolux Reverb (rated at 40 watts) using the same set of speakers. They both sound sweet and inspiring. I'd give that round to the Fender Twin though I think it is mostly because I liked the quality of the reverb of this particular Fender Twin better than the Vibrolux's. It maybe just a quirk in my particular amps and/or the "reverb tanks" used and may not hold true for other examples of these amps.

My '69 Twin Reverb has all original transformers. It has an original multi-voltage power transformer (selectable power voltage). I got this amp in a home-made head cabinet. I imagine that it would be cool to have a custom pine combo cab made for this amp. Hmmm...

According to the Fender code system, this amp was manufactured on the 25th week of 1969 (or June 1969). Just a month or two ahead of Woodstock that was held in mid-August 1969.

Teisco Model #62 Tube Amp

Teisco Model No. 62 Tube Amp
Made in Japan
Year circa '60s(?)





This is a one channel, Class-A (Single-Ended) all-tube guitar amp that puts out about 4W of power to one 6" speaker. There are four (7-pin) vacuum tubes specifically 2 x 6AV6 as preamp tubes, one 6AR5 power tube and one 6X4 rectifier tube.

This amp was marketed internationally under Teisco, Beltone, Northland, Takt and other brand names. There is a similar model with an additional 6AV6 tube and corresponding circuitry and controls for 'tremolo' effect. These 'tremolo' equipped models usually has 2 speakers.





It has 2 inputs, one volume and one tone control knobs, on-off switch and pilot lamp. I like the quality look and feel of the panel and its components.



The power transformer has a 110 and 220 Volt tap and a vintage knife-type SPST voltage selector switch.



There is very little information about teisco amps on the internet, I have not found any schematic so far.

I expect that the circuit would be very similar to vintage Gibson Kalamazoo Model One and Fender Champ 600 amps. The two 6AV6 preamp tubes in the Teisco would be equivalent to the two triodes (V1a and V1b) of the 12AX7 in the Kalamazoo Model One, shown below.


Schematic author is Miles O'neal of Austin, Texas and is originally from http://www.rru.com/~meo/Guitar/Amps/Kalamazoo/M1/schem.html

I added a phono plug and jack so that an external speaker can be conveniently plugged-in instead of the internal 6" speaker. I will fix the jack in a bracket to make it more secure and elegant looking.

Fender Reverb Unit (1966)

Fender Reverb Unit
USA
1966
Serial No. R10759

This is the legendary reverb unit from Fender that contains 3 vacuum tubes and 3 transformers. This is a 1966 model based on the serial number stamped on the chassis.

This unit works great and the reverb is the best I have heard so far. The reverb from this unit is even better than the already very nice built-in reverb in the also legendary Fender amps such as the Twin Reverb, Vibrolux Reverb, etc.

The amount and quality of reverb is controllable thru the "Dwell", "Mix" and "Tone" controls.




Tubes installed in this unit are all new: 1 x 12AX7 (JJ/Tesla), 1 x 12AT7 (JJ/Tesla) and 1 x 6K6GT (NOS Tungsol).




The cabinet is structurally sound and the front grill has no tear. The faceplate and the rusted handle shows the age of this unit. The backcover tolex has some tears in some areas.




This unit has been around for 40 years and is now ready to rock for another 40 years.

Yamaha SC-800

Yamaha SC-800
Serial No. 002139





The Yamaha SC-800 was made by Yamaha Japan from 1977 to 1980. The body is alder, the neck is hard maple and the fretboard is striped ebony.

It has Yamaha-made Single Coil Rail pickups in a standard strat configuration.
The neck pick-up is connected to a DPST toggle switch that can switch this pick-up ON and OFF. The middle and bridge pick-ups are each connected to DPDT switches. This allows the independent switching of the middle and the bridge pick-ups ON-OFF-ON, putting them in and out of phase.



I like the capability to turn off all pick-ups as it enables me to take a short break without needing to turn the amp off. It's like having a guitar cable with a circuit-breaker.

The hardware are all chrome-plated. The bridge is the fixed hardtail type with a tele-like string-thru-the-body arrangement for maximum sustain.







I like the fact that theYamaha SC-800 guitar has characteristics of both the strat and the tele.

The body is strat shaped and the pick-up positions are like those of a strat but the hardtail string-thru is like those of a tele. Having no trem mechanism means it has less cavities in the body than a strat and in this regard is more like a tele.

The flexible switching capabilities enable one to switch the pick-ups to any of the 5 strat positions. The neck and the bridge pick-ups can be switched like in a tele. Out-of-phase pick-up combinations are also possible for even more tonal variety!

Beautiful and possibly rare. They just don't make them like they used to!

Fender Vibrolux Reverb

FENDER VIBROLUX REVERB
SERIAL NO. 25861
1973













The Vibrolux Reverb is a particularly interesting model among the Fender Amps equipped with reverb. It is an excellent sounding amp with enough power (35~40W) and comes in a manageable size and weight package. This makes it very attractive to gigging guitar players. Its 2 x 10 speakers is also a plus factor as these disperses sound better than a 1 x 12 speaker does. A nice article that discusses these are here: http://www.tonequest.com/articles/article2.htm














This particular amp has been restored with:

--- All new Sprague Atom Electrolytic caps: 5 x 20uF/500V filter caps, 7 x 25uF/25V cathode bypass caps and 2 x 100uF/100V bias supply caps.

--- New Sprague Orange Drop cap: 1 x .047 uF/600V (to replace one that looked like it was gnawed on by a rat)

--- New set of JJ/Tesla Tubes: 4 x 12AX7, 2 x 12AT7 and 2 x 6L6GC

--- New Fender (EH) Tube: 1 x 5U4 rectifier tube

--- New Hammond Ouput Transformer replacement for VR

--- New Light Dependent Resistor (LDA) Optocoupler for the Tremolo

--- New Accutronics Reverb Pan: 4AB3C1B

--- New Filter Capacitor Cover

--- New Pilot Light Bulb













Now this amp works 100% with lush reverb and strong tremolo with no extraneous sounds. The amp is so quiet, I can not tell it is on if I do not look at the pilot light.

The sound from this amp connected to the 2 x 10" ceramic (50W capacity each) Eminence speakers in my Seymour Duncan 84-50 is beautiful and inspiring. The amp has more than enough power to shake your pants, the floor and ceiling - it makes your hair stand. You not only hear sounds, you feel sound waves through your body.

This amps original cabinet is beyond repair so that would be the one remaining issue to complete the amps restoration.

The Tonequest article recommends the 'blackface mod'. Now that I had this amp working and sounding so good as it is, I am inclined to keep the amp with no modifications. I listened to youtube videos of several SF and BF Vibrolux Reverbs and I feel that I like the sound of the SF more than the BF Vibrolux Reverbs.

The blackfacing mod and the reversal is relatively easy to do, I just might do it one day, just to confirm my preference. Now if I just can unplug my guitar and turn this amp off long enough to cool the tubes ....

The Harmony Central review, note that some reviews were for the new Custom Vibrolux Reverb: http://reviews.harmony-central.com/reviews/Guitar+Amp/product/Fender/Vibrolux+Reverb/10/1

Seymour Duncan 84-50 Tube Amp

SEYMOUR DUNCAN 84-50 TUBE AMP
US MADE
1992


















This is my first real guitar amp. It is a very nice 2-channel all-tube amp inspired by the VOX AC30.

It is equipped with 3 x 12ax7 and 4 x EL84 vacuum tubes and has an output rated at 50W. This amp has 2 x 10" 50W each ceramic Eminence speakers. It has a long-pan spring reverb with solid-state driver and recovery stages.

It has an effects loop and footswitch channel switching. An additional capabilty that is unique to this model is the quadra-verb channel and boost switch capability using an optional 4-button programmable footswitch.

I love the clean channel of this amp. At a specific setting recommended in the manual it has a fat and smooth overdriven sound. A Les Paul type guitar can drive this amp into a very nice overdriven sound without using any outboard effects. This amp is also pedal-friendly and it is very easy to get nice singing distortion sound using outboard effects.

Though marketed as a 2-channel amp, I view this amp as a very nice one-channel amp (clean channel) with a fooswitchable cascaded overdrive stage. The first 12AX7 is the preamp, the second 12AX7 is the OD cascade stage. The 3rd 12AX7 is the Phase Inverter tube.

















The internal construction is excellent and techies would be happy working on this amp.

It has one well-laid out thick double-sided pcb with most parts on it easily accessible. All wiring connections to the pcb (except one, the on/off switch connection) has push-type connectors and the pcb could be easily taken out completely for servicing. With regards to this issue, this amp is considerably better than even my Fender amps, vintage and pcb reissues and much better than similar VOX inspired amps like the Peavey Classic 30/50 and Delta Blues.




















The 4 power tubes are directly installed in the chassis, only the 3 pre-amp tubes are installed in the pcb. The above Peavey amps have their preamp and power tubes directly mounted on the pcb. Considering all the heat the 4 power tubes generate while the amp is "ON", this is another important advantage.

This particular amp model was purportedly designed by Randall Smith of Mesa Engineering for Seymour Duncan. This would explain why the original power tubes in the Seymour Duncan 8450 is a quad of Mesa Engg branded tubes (as also stated in the manual).

Amp Manual

Jester Oahu JU-28 Tube Amp

JESTER OAHU JU-28
Serial No. 0096















Jester Oahu JU-28 amps were hand-made by Jester Enterprises from 1998 to 2000 and are based on old Valco/Supro amp designs. This particular amp has 2 x 6v6GTs, 2 x 12ax7s and a 5Y3 tube rectifier. It has an Eminence 50W 10-inch ceramic speaker.

It is a class A push-pull design rated at 16.5 watts output.

The amp has 2 channels with 2 inputs each. It has an extension speaker out and a line-out with a level adjustment pot accessible under the chassis.

The amp's circuitry is very much like that of the 5E3 Fender Tweed Deluxe circuit. In the Gibson amp line, the closest equivalent are the Gibson GA-6 Lancer and Gibson GA-14 Titan amps. It has 2 VOLUME controls, one for each channel and a common TONE control.

The amp is hand-wired and the transformers are hand-built. The amp is beautiful inside and out. Oliver Archut, the amp maker used aircraft-grade thick aluminum chassis and the nuts and bolts used to attach the transformers to the chassis also appear like they were used in an airplane.

The lead dress and the grounding is very well executed and an amp tech would have no problems maintaining this amp.

The amp is quiet with no input and sounds excellent when played. A similar amp, an Oahu JU26 (also 6v6s power tubes, but in head unit form) can be seen and heard on "youtube". Search for keyword: oahu ju26

The cabinet is made of pine and nice plywood materials (no fiberboard here) and appears to be sturdy and thick. The gray/white tolex has a very nice deep texture and appears to be waterproof and easy to clean if that becomes necessary.













The amp has a 220V original power transformer so I am able to plug the amp directly to house power outlet without the need of a step-down transformer. Considering that only about 300 of these were made and ~50% were produced for Japan (100V) , Germany and Switzerland market (220V) and the other ~50% for the US market (110V), it is fortunate indeed to get a 220V model for use in the Philippines. This unit was obviously made for the German/Swiss market (220V power supply).













One customer who ordered units from Jester is Keith Richards (10 units in '96 and 20 units more in '06). Looking closely, the amp can be seen in some of the newer youtube videos of the Rolling Stones.

The majority of the 300 or so Oahu amps units made use EL84 power tubes according to the Jester site. This maybe why Jester did not bother printing labels for their 6V6 amps. The amp label inside this amp show EL84 power tubes though it actually use 6V6s.

I consider having this unit with 6V6s a definite plus as this is the only amp I have that uses this type of power tube. I have bigger EL84 and 6L6 powered amps and welcome the tonal variety this amp offers.

Gut Shots:



















The 50's Valco Oahu Amp Inspiration

1964 Blackface Fender Showman Amp Head

FENDER SHOWMAN BLACKFACE TUBE AMP HEAD
1964 PRE-CBS
Serial No. A01784
















This is the top-of-the-line Fender amp at the time of its production. It puts out 85 Watts of all-tube power courtesy of a quad of 6L6GC power tubes.

This particular amp has its original Power Transformer, Choke and Output Transformer.













Power Transformer: 125P134AX/606-403 (manufactured 3rd week of 1964)

The "X" designation means that the Power Transformer has multi-voltage taps for International use. This is a plus factor in the Philippines where the local power is 220V.

Choke: 125C1A/606-420 (20th week of 1964)

Output Transformer: 125A30A/606-436 (36th week of 1964)

Filter, Bypass and Bias Supply Caps: all are newly installed Sprague Atoms.

Tubes are new JJ/Tesla: 3 x 12ax7, 1 x 12at7 and 1 matched quad of 6L6GC.

1969 Silverface Fender Bassman Tube Amp Head

Fender Bassman Tube Amp Head
1969
Serial No. A48572
















The 50 Watts Fender Bassman tube amp head has two independent channels and use 4 x 12AX7 and 2 x 6L6GC.

This particular amp is quite unique having the word "EXPORT" in the amp name on the faceplate. Most Fender amps for international market (installed with multi-voltage transformers) does not have the word "EXPORT" on the faceplate.

I've come across one from the internet:

http://www.stinkfoot.se/andreas/amps/amps.htm

This particular amp sounds great and is quiet (no hum, crackle or hiss); one of the great sounding classic Fender Amp. Its got the sparkling Fender clean sound with a full and tight bass. The big output transformer in the Bassman and the short and direct signal path contributes to its signature clean sound.

Dumble used the Bassman as the basic platform for the 50 Watts ODS amp. The ODS50 use all of the three transformers from the Bassman. A small 6-Volt transformer was added to supply power for the switching relay circuit.

There are a few owners of this amp who converted their amp to a Dumble ODS50 clone (there are examples of this on youtube). Major components from the Bassman such as the transformers, chassis, tubes, pots and switches and some other components can be used for the conversion.

Many owners leave their Bassman unmodified and enjoy them as they are; a great amp with the classic Fender clean amp sound!

Washburn Bass King Jr. VBA-15 Amp

Washburn Bass King Jr VBA-15 Amp
MIJ
100V

This is a Solid-State amp that puts out 15 Watts to a 1 x 10" speaker. There is not much info about this amp, but it is obviously a well-designed and sturdily built small practice bass amp, made in Japan for the Japanese market. Though it has a fully covered back, this amp can also be used as a guitar amp by tweaking the tone and presence knobs.

This amp appears to be well-built and the nickel-plated hardware, (faux but beautiful nonetheless) tweed cover and chickenhead knobs indicates to me that this not an economy model practice amp. It is obviously a copy of the Fender tweed cabinet design.

This is an excellent practice bass and guitar amp as it is light and portable and has an earphone jack for late night practice.

Fender Pro Jr Tube Amp

Fender Pro Jr Tube Amp
Made in USA
220V (export model)
Jensen P10R Speaker

























Pro Jrs have 2 x 12ax7 and 2 x EL84 tubes putting out 15 Watts of pure valve power to a 1 x 10" speaker. One volume and one tone control, nothing could be simpler. You can set the amp to your favorite setting and forget about it. You then control your sound using the controls in your guitar.

The tweed cabinet is beautiful and sturdy and the amp is light and portable, a very nice grab and go amp.

This is one loud 15 Watt all tube amp and many have used Pro Jrs for gigging, unmiked or miked for bigger venues.

The Pro Jr has earned a lot of praise from owners and users:http://www.fenderforum.com/forum.html?db=&topic_number=233659&lastpost=2008-09-2910:16:13