“…this is a magic circuit…” – Joe Walsh on his Z-Master Signature Amplifier


Power Output30 Watts
Output Tubes2 – 5881
Preamp Tubes3 – 12AX7
Rectifier1 – 5AR4
ControlsVolume 1, Volume 2, Bass, Treble, Presence
Other4 Ohm External and Internal speaker outs
Configuration3×10 Ultra-lite Combo
Dimensions and Weight22″ W, 21 1/2″ H, 10 5/8″ D; 42 lbs.
Owner’s ManualDownload

General Information

In 2018, Joe Walsh approached Dr. Z to recreate his favorite amp of all time: a ’59 tweed Bandmaster 3×10. While touring in the early 70s with the James Gang, Joe gifted his original ’59 Bandmaster to particular wind-milling British guitarist who next recorded a classic 1971 album using the amp. 50 years later, Joe tasked Dr. Z with recapturing the magic of the “one that got away.”

Starting with a to-spec replica of the paper wound, model 1848 output transformer by Triad Magnetics (the manufacturer of the original transformers of the tweed era), Dr. Z made an exacting recreation of the Bandmaster and sent it off to Joe, who was ecstatic with the resulting amp. Later in the year, after Joe requested some tweaks and alternations, Dr. Z completed the first prototype of what would become Joe’s signature amp: the Z-Master.

Though rooted in the ’59 Bandmaster, Dr. Z and Joe designed the Z-Master to suit his playing style and his vast, unique collection of guitars, resulting in what he would authentically deem his “signature amp.” These particular adaptations include the independently voiced “Vol. 1” and “Vol. 2” controls that are internally blended, as to achieve a tonal balance to suit the specific nuance of both the player and their guitar of choice. On Joe’s request, Dr. Z also pumped up the power supply of the amp to welcome the bevy of effects on Joe’s pedal board, creating a sustaining clean tone full of detailed shimmer and percussive punch. The Z-Master is suited for the modern pedal effects player providing ample clean headroom early on the volume controls, or for the guitarist who simply wants to plug in and crank up, just swing the volume dials clockwise to unleash thick, tube overdrive and saturation from the alnico speakers.

The Z-Master has been road-tested through the 2018 concert calendar serving as Joe’s main amp on stages worldwide. The Z-Master pumps out 30 watts through its unique 3×10 speaker configuration. It uses three, 10” paper voice coil, alnico speakers in a parallel wiring configuration, specifically designed for this amp. This creates an intentional impedance mismatch between the speakers and output transformer, which is an integral part of the sonic recipe of the amp. As the first “signature series” amp in Dr. Z history, the Z-Master exhibits a wholly uncanny voice not unlike the man himself, Joe Walsh.


“As a fan of late ’50s Fender tweed amps I have to say that I was hopeful that this amp really would deliver the goods with the effort that Joe Walsh and Dr. Z put into it. I’m very happy to say that the amp is simply fantastic. It’ has the huge low end you’d expect from the circuit and large cab. The swirl of the 3 speakers is there as is the “bouncy” and lively big tweed sound. It’s clear that the work really went into this amp to make it very true to the magic of the ’57 Bandmaster. The ability to balance the warmth and attack of the amp by simply balancing the two volume controls is a very cool aspect of this amp. I leave the tone and presence controls at noon and simply dial in the amp with the volume controls. It’s also nice that the volume comes up in a linear way. You can play this amp in a bedroom or on a big stage. This Z-Master is an absolute gem!” – John Fox, Corvallis, OR

“I just took delivery of this Z-Master this past Friday and pulling it out of the double boxing, (outer box by Sweetwater and inner sturdy, classic Dr. Z shipping box), I was immediately impressed by the smaller size and lighter weight of this amp! Nice! From the first few notes I knew this was a different style offering from Dr. Z. This was the Tweed Tone I was hoping and expecting. Open, sparkling high”s and piano string, deep lows. All while sounding very sweet with the Tweed type sponginess. Very cool. At 30 watts it”s a nice, loud tweed clean tone with single coils up to near noon. After that more breakup and volume…of course. I have a Tweed Super replica (2-10″ 28 watts) and a Tweed Twin low power replica (2-12″ 40 watts), both great amps and this one sits right in the middle of those two. Just as it should. I sounds fabulous at low volumes and even better as you turn the dual volume knobs to the right. The speakers are a big part of this recipe and another departure for Dr. Z. Low efficiency, vintage sounding AlNiCo”s. I’ve tried several boost, overdrive and fuzz pedals, along with delays, reverbs, vibes, tremolo and compressor pedal all with great results. I’ve owned many different Dr. Z amps and like them all. This one is decidedly different. A special amp and looking forward to more time with it. Thanks Dr. Z and Joe for releasing this to the public and Sweetwater for offering it!” – Mark Tyson, Taylors, SC

Share This: