Dr. Z Amplification

Z-PLUS

“Being a true class A design… it has that inherent quality of adding a layer of second-order harmonics to the sound, and you can hear it in the complexity and dimension this amp delivers. ” – Guitar Player Magazine

Specifications

Power Output	7/15 Watts (half power mode)
Output Tubes	2 – 6V6 (Class A, cathode biased)
Preamp Tubes	4 – 12AX7, 1 – 12AT7
Rectifier	1 – 5AR4
Controls	Volume, Treble, Mid, Bass, Cut, Master Volume, Reverb
Other	4, 8, 16 Ohm Effects loop Variable Boost Footswitch Parallel, Single-Ended Design
Configurations	Head, 1×12 Studio Combo, 1×12 Ultra Lite Combo
Dimensions & Weight	Head: 19” W, 9 3/4” H, 9 1/2” D; 32 lbs. 1×12 Studio Combo: 19 ¼” W, 19 ½” H, 10 ½ ” D; 38 lbs. 1×12 LT Combo: 22 1/2” W, 20 1/8” H, 10” D; 40 lbs.
Owner’s Manual	Download

General Information

When Joe Walsh approached Dr. Z for a new amp to use on the latest Eagles’ tour, he harkened back to the legendary recordings with the James Gang, where Joe was using small, single ended Tweed combos. Never one to be satisfied with rehashing old designs, Dr. Z and Joe Walsh upped the ante by looking to hi-fi audio amplifiers; from this the Z-PLUS was born.

The Z-PLUS is a parallel, single-end amplifier in true Class A configuration, which yields a rich clean tone that smoothly overdrives into gritty, harmonic-laden distortion. Single-ended, Class A operation produces full even-order harmonics which are typically cancelled in traditional push-pull, Class A/B tube amp designs. The result is sparkling and satisfying tone with the full range of 2nd and 4th order harmonics with clarity akin to an full bodied, acoustic guitar. While typically class A designs are limited by lower clean headroom, the Z-PLUS utilizes two 6V6 power tubes in parallel which increases clean headroom, per Joe Walsh’s request.

For the best of both worlds, the inclusion of a half-power switch drops the second 6V6 out of operation, rewarding you with touch responsive drive, dynamic compression, and lowered headroom. All of the typical Dr. Z features are included: full EQ with master volume and cut, hi and lo sensitivity inputs, an effects loop, a rich reverb circuit, and our variable boost footswitch. The output transformer is a special design for this amp, constructed with the highest grade M-6 stacked laminates, coupled with our custom all-aluminum chassis, and built like a tank to UL-60065 specifications. The Z-PLUS is available in our standard Ultra-Lite 1×12 combo or smaller studio-lite combo with either a ceramic Z12 Eminence designed speaker, or an upgraded Celestion Alnico Blue.

Joe Walsh on the Z-PLUS

“I recorded ‘Funk 49’ with a Telecaster straight into a blackface Champ with an 8″ speaker and one output tube, and that’s why it sounds like it does,” says Joe Walsh about what he was seeking when he asked Dr. Z founder Mike Zaite to design a new amp for him. “That sound mystifies most guitarists. Single-ended amps can be magic in the studio, but they don’t work at all for live performance. I call up Z sometimes and we talk amps, so I said to him, ‘How do we get a Champ sound at stage volume?’ As usual, Z goes, ‘I don’t think you can do that, but let me think about it.’ Then, he calls me in the middle of the night and says, ‘I’m in the shop, and I’ve got a couple of ideas. I’ll get back to you.’ The result was two output tubes wired in parallel, which keeps the amp single-ended, but it’s way over twice as loud. No push-pull, no phase-splitter, no biasing issues—none of that. It’s a high-powered Champ offering a world of new sounds with any pickup. You should hear ‘Funk 49’ through it. Thanks, Z. U da man!”