Two Silvertone Amps + Boss CE-3 = Stereo!

Boss CE-3 Chorus

I love stereo! That’s why I got pretty excited when I looked at my Boss CE-3 chorus pedal and realized I could connect a pair of amps to the CE-3′s dual outputs and play my guitar in stereo. So I decided pick up two inexpensive Silvertone 1421′s (aka: Sears 10XL) off eBay. These are great little tube amps from the late 60′s and early 70′s. The 10-watt 1421 uses two 12AX7 tubes—one for pre-amp and the other for tremolo—and a single 7189 as the output tube. The 7189 tube is the industrial version of the venerable EL84, a tube found in so many British valve amps. The 12AX7/EL84 tube combination is unique to the 1421 amp within the entire Silvertone line, and compares it nicely by design to the original Vox AC4 Combo of the early 60′s.

Silvertone 1421 Original
Silvertone 1421 Original

This first amp is a beautiful 1971 model, completely original and in excellent condition. The Sears model number is 257.14211100. It probably sat in someone’s closet for the better part of 30+ years and was hardly played. Except for a power switch stuck in the “on” position, the old two-conductor power cord, and a little bit of hum, this combo is totally functional and sounds great. It even has its original protective vinyl cover (I’ve never seen a cover for these before) and its original tremolo foot switch. The original grill cloth is in great condition, which is truly rare for this model, even though it does have one cigarette-sized hole in the fabric. The speaker is an 8-inch Oxford Alnico magnet speaker that rings clear at low volume, but breaks up nicely when cranked (along with the tubes in overdrive). All in all, this little combo is a real sweet find! After I fix the power switch and replace the cord, I plan to keep this guy all original. I can live with a little hum for now.

Silverton 1421 Grill Cloth Replaced
Silverton 1421 Grill Cloth Replaced

The other amp is a 1970 model 1421. Also Sears model number 257.14211100. It’s in pretty good condition too, and is almost completely dead quiet (no hum) when running. But the original grill cloth was replaced and the tremolo is not working. Somebody already replaced the notorious power switch and the 2-prong power cord before I bought it. Unlike it’s twin, this 1421 has an 8-inch CTS speaker with ceramic magnet. I plan to mod this amp as my next project. I will need to work on the tremolo circuit, then replace the caps, ditch the ugly brown fabric, and build a new baffle board to hold a bigger 10-inch Alnico Blue speaker (think: Celestion). After those mods are complete, this 1421 should sound more British than American.

Then, plug these two into my CE-3 stereo chorus pedal and have fun!

A full Tone Gems review of the Silvertone 1421 will be in the near future.

Oak Crest Talent Show 1961

We enjoy receiving blog comments and emails from readers who are as passionate about music and guitars as we are here at Tone Gems. Recently, Ray Clearwater – who incidentally publishes 25 Years of Sears Musical Instruments on CD – shared a old photograph of his 1961 Junior High talent show.

Brand New 1984 DOD FX50 Overdrive


Just arrived! A 1984 DOD FX50 Overdrive Preamp in like-new condition, in the original factory box. There are plenty of these pedals out there, but this one has been barely used and came along with the original manual, papers, and schematic diagram. Plus, I got a great deal! Can’t wait to try this out and report back on the tone.

Brand New 1967 Teisco EP-7, Checkmate Amp

Drop dead, new old stock guitar, amp and accessories.

A guitar time capsule discovery. While out trolling the flea marts, pawn and antique shops today, Jon and I ran into this absolutely beautiful 1967 Tesico EP-7. It came with its original matching Checkmate 12 amp, guitar strap and cables. It was entire ’67 Teisco electric guitar starter package, minus the original gig bag (but the seller might have had that hanging around, too). Even though the set was 45 years old, the guitar and amp were as new as the day they came out of the Teisco factory. Someone must have received the set back in ’67 and then locked it on a closet. The nitrocellulose finish was perfectly glossy, the chrome was gleaming, and the rosewood fingerboard and brass frets appeared to never have been played before today. We did hear some hum coming from the solid-state Checkmate 12, but that may have been caused by the super-cheap unshielded guitar cable we were using. The EP-7 sounded just “OK” through it’s little solid-state amp. But when we plugged it into a ’47 Harmony tube amp, those two single coil pickups really began to shine. We were impressed by this little guy. It was the find of the day, and maybe the year.

Another Silvertone Christmas

Another Christmas; another Silvertone surprise!

Last year it was the snazzy electric Silvertone 1445 that showed up under the tree. This year it’s the diminutive 1956 model Silvertone 605 parlor guitar. It must have been misplaced in the back of Santa’s sleigh for some 55 years?

The 605 is a small body, short scale, acoustic flattop with a solid birch top, birch sides and back. These sturdy little guitars were made in Chicago, Illinois for Sears by the Harmony Musical Instrument Company. They were popular with the rhythm and blues crowd and they made great slide guitars. This one is in very good original condition with just a few minor surface scratches here and there. The size is perfect for traveling, so it will be a fun guitar to knock around and take anywhere.

The Silvertone 600 Series of parlor guitars were sold through the Sears Catalog continuously from 1948 through 1970 (that’s 22 years of production). In fact, a 1961 model of this guitar was played by Audrey Hepburn in the movie Breakfast at Tiffany’s. This 1956 model originally retailed in the Sears and Roebuck catalog for $10.95. Here is a cut from the 1956 Sears Catalog.

For more information about the Silvertone 600 Series and the 605, see Silvertoneworld.com and the Harmony Database.

Tags: 605, Audrey Hepburn, Birch Blues Box, Blind Willie Johnson, Breakfast at Tiffany’s, Catalog, Django Reinhardt, H-605, Harmony, Leadbelly, Moon River, Robert Johnson, Sears, Silvertone, Slide Guitar

Kay Vanguard 704 with Vibrato

Kay 704 Vanguard Vibrato

“A Briefcase Full of Blues” – The World’s First All Solid-State Guitar Amp

Quick Info

Summary: 1965 5-watt solid-state combo amp with built-in vibrato effect; 8-inch Alnico speaker; seven Germanium transistors and five Germanium diodes. Point-to-point hand soldered. Perfect little amp for practice or recording.

Pros: Vintage 60′s tone. Extremely compact and portable design. Vintage Germanium transistors and diodes. Simple chassis layout.

Cons: Cheap, lightweight construction and paper-thin fabric covering (but hey, it’s lasted this long already).

Surprises: This old school amp designed more like a tube amp than a solid-state amp. The 8-inch Oxford Alnico speaker sounds great! Awesome vintage vibrato circuit.

Value: Street prices vary by condition and demand, but the price of these continues to rise.

Similar Amps: Kay 700, 705 and 706 of similar vintage. It’s possible, but not certain, that there may be some similar Kay-built amps with a Truetone (Western Auto) label.

Introducing the Kay Vanguard Series

In 1962, the Kay Musical Instrument Company of Chicago introduced the Vanguard line of guitars and amps. That new line included the Kay Vanguard Amplifier with Vibrato, Model 704 (Model No. K-704). The Vanguard 704, along with other Vanguard amp models 700, 705 and 706, were the world’s first mass-produced all-transistor (solid-state) guitar amplifiers. While some transitional hybrid amplifier circuits had previously existed, which paired solid-state electronics with traditional vacuum tubes, Kay was the first company to offer a full line of exclusively solid-state amps to market in ’62. The Vanguard 704 was part of that line and was frequently seen offered with the Kay Vanguard solid-body electric guitar.

A marketing advertisement from 1965 says that the K-704 was built with seven transistors and five diodes.

A Compact Design

In contrast to the heavy, boxy, amplifiers of the 1950′s, the engineers at Kay set out to create a new series of amps styled for the Modern Space Age. The new Vanguard Series was designed to be compact, lightweight, sleek in appearance. Finished in a rad two-tone pattern, the tapered vertical design had a top mounted control panel, and a cabinet barely deep enough to house the speaker and chassis. The new look was unique for a guitar amp of the day and remains unique today. However, the lightweight cabinet materials made it more prone to excessive wear and tear. Therefore, not many of these amps have survived.

The Controls

The Vanguard 704 features three instrument inputs into a single channel; a volume control and a tone control. The power switch is built into the tone control knob. The vibrato controls include speed, strength, and a jack for a foot switch. A sturdy brass handle is ready to go places.

Old Germanium, New technology, Old Circuit Design

What really makes the Vanguard 704 interesting today is its 1960′s Class A amplifier design and chassis layout. Since solid state technology was still relatively new at the time, the Kay engineers built the preamp, vibrato and the output circuits similar to the old tube circuits, except using Germanium transistors and diodes substituted for vacuum tubes. Because of this design the K-704 sounds akin to its tube cousins of the day. Based on traditional tube amp design of that period, the vacuum tubes were replaced in the hand-wired circuits with seven Germanium transistors and four diodes. The old Germanium transistors sound a little “looser” than the newer Silicon versions, which make them perfect for these low wattage amps. However, Germanium never could handle the heat and raw power of higher watt amps. But Germanium still has a following and is used in low voltage applications, like custom built effects pedals.

According to the pots, it’s a 1965 model. Completely original. A 5-watt wonder. It’s circuits and layout are traditional for the period, but seven germanium transistors and four diodes in place of the traditional vacuum tubes. A single front-loaded 8″ Oxford Alnico speaker. Not a whole lot of lower mid-range. But then again, no low end speaker flab either. The tone kinda reminds me of Led Zep. Mild overdrive at full volume from my Gretsch 5120 humbuckers. Growling, howling overdrive from my Silvertone 1445 with Teisco single coils.

Vibrato, CCR, and The Midnight Special

The vintage Germanium powered vibrato circuit stirs up a deep swirly tremolo that simply sounds awesome. The Kay Vanguard with Vibrato is perfect for nailing that stirring, swelling, sound that Creedence Clearwater Revival played on songs like The Midnight Special and Run Through the Jungle, and other great CCR recordings.

If you are a fan of that vintage 60′s and 70′s tremolo, then this effect alone was worth the price of this unit.

Features

  • Compact, ready-to-go “suitcase” design.
  • Two-tone fabric over wood construction.
  • Five watts output.
  • 7 Germanium transistors.
  • 4 Germanium diodes.
  • 8-inch Oxford “Heavy Duty” Speaker with Alnico magnet.
  • One channel.
  • Three inputs.
  • Vibrato speed and depth controls; foot switch.
  • Volume and tone controls.

Specifications – Kay 704

KAY 704 – VANGUARD with VIBRATO
Model Number 704A
Serial Number 9366
Manufacture Date 1965
Type 8″ Combo Amp
Output (Peak or RMS) 5 Watts, Peak
Pre-Amp Transistors 2N2613, 2N408 and 2N591 Ge PNP BJT, RCA USA
Vibrato Transistors 2 ea. 2N408 Ge PNP BJT, RCA USA
Power Transistors 2 ea. 2N545 Ge PNP BJT, Motorola USA
Speaker Configuration 1 x 8″ Rear Loaded
Speaker Oxford 8ES-9 Alnico Magnet
Speaker Code 465-510 (10th month of 1965)
Baffle Board 1/4″ Plywood
Impedance 8 Ohm
On-Board Effects Solid-State Vibrato
Footswitch Yes
Controls Volume & Tone
Inputs 3 Instrument Inputs
Channels 1
Cabinet Construction 3/8″ Plywood
Cabinet Covering/Color Fabric
Dimensions (WxHxD) 14″x17″x6″
Weight 8 lbs.
Power 120V AC

Schematic Diagram and Parts List for the Kay 704A

Original factory schematic diagram as photographed from inside the 704 chassis.


Original factory Bill of Materials (or, “parts list”) as photographed from inside the 704 chassis. Notice that transistors Q1, Q2, Q3 and Q4 are all Germanium transistors made in the USA by RCA and Motorola, as well as diode D1.

Additional Resources

Links to additional information.

Photos: See more photos here.

Comments

weldon January 1, 2014 at 12:04 am

i had a 704 kay amp and kent guitar in the 60s they were new—–i had to pawn them to move away–i found a kent guitar and now looking for the amp-can you help thanks weldon bent

REPLY

alex January 1, 2014 at 9:13 am

Weldon,
Thanks for stopping by the website. 704 amps are hard to come by these days. Not many survived the 1960′s. Ebay is probably your best bet, as I see a few show up there each year. Craigslist another option. Good luck!
~alex

REPLY

big gee February 1, 2015 at 1:56 pm

I have one of these 704 Kay in great condition for sale make an offer

REPLY

Tom J April 7, 2015 at 4:28 pm

I have a Heater II reverb amp type 58 with the tag that says “Manufactured by beautiful girls in Milton, Wis.
under controlled atmosphere conditions”.
Can you help me get a schematic ?

REPLY

alex July 26, 2015 at 9:58 pm

Hi Tom.
That reverb unit was made by OC Electronics and was used in many amplifiers sold by Sears, Wards, etc. in the late 60′s early 70′s. I don’t know if a schematic is available, but you might try Schematic Heaven.

REPLY

25 Years of Vintage Silvertone on CD


Here is a must-have for all vintage Silvertone fans. It’s a CD containing 25 years of Silvertone guitars, amps, and other musical instruments offered from the original Sears catalogs. The pages cover Silvertone products for each year from 1950 through 1975. The CD was created by Ray Clearwater of Morro Bay, California, and can be purchased on eBay or directly from Ray for $12.95, plus $2.00 shipping.

There are a total of 126 catalog pages all scanned at high resolution and saved as color JPEG’s. Also included are some articles compiled by Ray about Silvertone, Danelectro and music from the 50′s and 60′s. Ray says that this CD is a labor of his own appreciation and childhood memories. He adds, “It was my feeling that as I really enjoyed going back and looking through the guitar pages that I dreamed about as a kid, it might also be of at least some sentimental value to others as well.”

Here is the link to the eBay page: SILVERTONE – DANELECTRO – KAY – HARMONY – SEARS CATALOG PAGES 1950 TO 1975 ON CD. You can also contact Ray by email at ohcisco2001@yahoo.com.

Here is a catalog page from 1964. This page is a real winner in itself! The black hollow-body is a sought-after classic, owned and played by Chris Isaac. The red one is a favorite of Dan Auerbach of the Black Keys. Both were built for Sears by Harmony in Chicago, Illinois.

The pages have been carefully scanned and contain invaluable information, specs and original prices of old Silvertone guitars and amps built by Danelectro, Harmony, Kay, Teisco, and others from the 50′s, 60′s and 70′s. It is definitely worth the $12.95 plus shipping.

Univox UB-250 Bass Amp Video


The UB-250 is a late 60′s solid-state piggy-back (aka mini-stack) bass amp built by Univox in Westbury, New York. These were continuously made through the mid-1970′s, but this is the original design and build from 1969. Although it’s not the loudest of bass amps, it is a vintage cool analog alternative for any beginning bass student.

Sorry for the poor video and audio quality. We really need to work on improving our videos!