1964 Airline 62-9013A

The Airline 62-9013A was Montgomery Wards answer to the Silvertone 1472. By “answer” I actually mean a total and shameless clone of the 1472. The Airline brand of amps were all like this - they copied the unique and often great engineering that Sears Roebuck had put into the Silvertone line. Silvertone (and Airline) were designed from the ground up - they did not in any way copy the Fender/Marshall/Vox circuits that were the mainstay of schematic design at the time. This resulted in amps that sound like no other brand - which has only recently been acknowledged and revered. These were considered “student” amps at the time. Although the circuit engineering and sound are very good, both companies cut major corners on construction quality in order to make amplifiers that literally anyone could afford. The use of cheap particle board cabinets, instead of the normal sturdy choices of pine or baltic birch plywood, is the biggest offender - which means many of these amps can have issues with the “wood”. Speaker choices were often Jensen’s or a knockoff of Jensen. Inside the amps are wired true point-to-point with the use of terminal strips. This amp is often called the “poor man’s Deluxe” due to the similar tube lineup and speaker/cab dimensions of the Fender 5E3 Deluxe. Silvertone and Airline amps have had a resurgence lately due to their well known usage by Jack White of The White Stripes, and Dan Auerbach of The Black Keys.

This amp came in to my shop in completely original condition. This one needed a full restoration including a cap job, new power/misc. resistors, cleaning, 3 prong AC cord conversion, and a new speaker. The customer wants to gig this amp so putting a modern high quality Weber brand speaker in it will help with reliability.

The amp was fully restored. A complete cap job was done including the electrolytic cap can, which was replaced with a custom circuit using axial leaded electrolytics and phenolic terminal strips for the filter section. The caps used were CE brand units with upgraded temperature ratings. This was done because the original multi-section cap had an unusual 1" diameter and there have been no replacements available for decades. If it had been the usual 1 3/8" diameter type can we could have gotten any number of new reproductions. The bypass capacitors were replaced with CE/Mod brand electrolytics with upgraded voltage/temperature ratings. All of the paper/foil and wax signal caps were replaced with Mallory brand 150 series and CE brand polyester film capacitors respectively. The old 1/2 Watt Carbon Comp power resistors were replaced with upgraded Reduced Mass 2 Watt Metal Film type units. This was done due to heat damage, noise, and drift of the original parts. The higher wattage resistors mean better reliability and a lower noise floor. A new 3 prong AC cord was installed to replace the old 2 prong unit and the death cap was removed. A brand new correctly sized 3AG 250V fuse was installed as the one in place was the wrong value.

I also put a couple of mods into the circuit of Channel 2 to help bring a bit more gain and fuller/brighter frequency response to the amp. Both channels have two inputs all of which are identical in tone - because of this I wanted Channel 2 to stand out and offer something unique. As this amp can be a bit dark with humbuckers I decided to tune CH. 2 for better results with these pickups. The V1b cathode was bypassed with a 1uf 50V cap (treble/upper mid boost). The CH. 2 volume control had a 500pf 500v Silver Mica treble bleed cap added to increase brightness, especially at lower volume levels. They really brought the amp to an elevated level of tone that wasn’t there to begin with.

The customer wanted the speaker changed to a model that was in line with what would have been in the amp originally but that was made with better parts and had a beefier wattage rating. A new Weber 12A125A 30 Watt 12” Alnico Speaker (Light Dope @ 3.2 Ohm) was installed to replace the original unit. This is Weber's take on the early 1960's Jensen P12Q - an extremely close and high quality reproduction.

All of the original tubes tested good and were kept in place. The final lineup was: V1/V2 = Westinghouse 12AX7A, V3 = RCA 6X4, V4/V5 = RCA 6V6GT Matched Pair, V6 = RCA 6AU6A. The 6V6GT's Cathode Bias was set to a conservative 79% Class AB Plate Dissipation with a B+ of 275VDC. With amps that have bias-modulated Tremolo like this one, the hotter you set the bias the weaker the effect will become - the phenomena plagues many old amps that were setup incorrectly over the years by techs that don’t understand this balancing act. The tube sockets were all cleaned with a De-Oxit treatment to prevent noise from corrosion. The pots were sprayed out and the amp was cleaned inside and out.