Vintage Tube Amp

Up for sale, a 1962 Gibson GA-79RV in excellent condition and in perfect working order, complete with the original footswitch. A true stereo affair, the GA-79RV features a V front cabinet with two 20 watt channels pushing individual 10 Jensen ceramic magnet speakers. The quad of 6BQ5 (EL84) power tubes deliver a healthy 40 watts of all tube power when run in mono, and these tubes have a crystalline top end and heavenly overdrive, delivering a distinctly Vox-esque sizzle and roar when diming out the circuit. The cleans are snappy and clear too, with appropriate headroom before the circuit cascades into touch-sensitive bite and crunch. Exclusive to Channel 1, the tube-driven Reverb is lush and splashy, and given the stereo operation, the GA-79RV also offers the unique opportunity to mix the effected signal of Channel 1 with the dry signal of Channel 2, with a distinctive cabinet design that fills a room with dimensional tube tone. The circuit has been freshly and professionally serviced, with original transformers and a recap of the power supply with F&T capacitors. The tidy tag board circuit features a bevy of original carbon comp resistors and molded signal caps, and the CentraLab pots have visible date codes from the 38th week of’61. The vertically mounted reverb tank has a date stamp from the 2nd week of’62. The tube complement includes a modern quartet of Sovtek EL84 power tubes, with all vintage valves from the likes of RCA and GE in the preamp. The chrome-plated faceplate has plenty of shine, with all of the original black silkscreened text intact as well as all of the knobs. The speakers have been replaced with a modern pair of Jensen C10Q ceramic magnet 10 drivers. The original footswitch is included too and hard-wired, allowing easy activation of the Reverb, and fitting in its original metal bracket for transport central to the lower back panel. The original textured dark gray tolex and wheat grillcloth are extremely clean, and particularly notable, the entire original plastic Gibson badge is intact central to the face of the amp (a true rarity).

This particular tube tests very strong, although it’s not the most balanced tube. Often square-getter Mullards are associated with mC1 production codes, and the halo-getter tubes with f91 and later codes. Oddly though, this particular tube has an f91 code AND a square-getter. The f91 code on this tube is Extremely faint, and is almost impossible to see with a naked eye even under good light (and even more difficult to photograph, but I think I managed to barely capture it with a back-light enough to sort-of see it’s faint outline). The print on the tube is very fragile and will easily rub off, some has already rubbed off, special care was taken not to rub off any more while testing. The tube’s test results are displayed in the photos (New 12AX7 Spec 100% = 1,600 Gm). See the photos for physical / cosmetic condition. Part of the design is a little springy shock absorber the keeps the tube safely centered in the box and from rattling around. Notes Regarding Tube Tests. All tubes are tested on an Amplitrex AT-1000 tester in the automatic Fixed Bias Mode (for the most conservative results). Test Results are for a general reference only, and are not a guarantee of performance, nor a guarantee of how they will test on your tester. No real world (audio) performance measurements are taken.