Overdrive based on the vintage Vox 4 and 7 series amplifiers
By Phil O'Keefe
The Beatles Revolver LP and the Paperback Writer / Rain single. The Rolling Stones Between The Buttons LP. Led Zeppelin II. What do all of these legendary recordings have in common? The ultra-rare and very hard to find VOX UL 7 and UL 4 series amplifiers. These UK-built hybrid amplifiers were made for a very short time, and most estimates suggest that probably fewer than one hundred of each model in the series were made. Of course, they're now pushing fifty years old, and with a recorded pedigree like that, they are also in fairly high demand, making your chances of ever finding one, much less affording it, very low indeed. Featuring a solid state preamp section that was inspired by the USA-built Thomas Organ VOX solid state amps such as the Super Beatle, the power amp sections were all tube, and used a variety of different tube types, depending on the model and rated power, with amps such as the 30W UL730 using EL84 power tubes, while more powerful models such as the 120W UL7120 and UL4120 used KT88 power tubes. It is the sound of these rare hybrid amps that the Lumpy's Tone Shop Lemon Drop and ZII attempt to recreate. Built in Altoona Pennsylvania by Tommy Castellucci, the proprietor of Lumpy's Tone Shop, all aspects of the construction are done in-house.
What You Need To Know
- Inspired by the ultra-rare VOX UL4 and UL7 series hybrid amplifiers (the 4 series amps were intended for bass and are essentially identical, except they lack the reverb, fuzz and tremolo circuits of the 7 series) which were popularized by the Beatles, Rolling Stones, and Led Zeppelin, the input stage of the Lemon Drop / ZII is based directly on the input of the amplifiers. The pedals use a silicon transistor for the first gain stage, pushing a FET into clipping to simulate a tube output stage like the ones used in the original VOX amplifiers. This "pseudo hybrid" design works quite well, and does a great job of emulating the sound of the amps.
- Lumpy's Tone Shop offers this pedal in two different versions - the Lemon Drop, and the ZII. Internally they're identical, and only the external graphics differentiate the two models. The Lemon Drop is finished in a powder coated yellow, with black lettering, while the ZII (the unit under review) features a silver-grey Hammertone powder coated finish, with black lettering. The font used for the labeling on the ZII will probably look quite familiar to Zeppelin fans. The black lettering and overall cosmetics of the pedal look very cool, although the labels can be a bit hard to read against the grey background, especially on a dark stage or dimly-lit studio.
- There are three controls on a standard Lemon Drop or ZII. The knobs are different, depending on which version you get. One cool little extra on the ZII version is that the vintage-style skirted knobs are numbered, and "go to 11."
- The Volume control sets the overall output level. There is plenty of level on tap, so you can easily boost levels above unity when needed. The setting will vary depending on where the Drive knob is set, but typically unity gain is somewhere between 3-5 on the ZII's volume knob, or in roughly the 10 o'clock range on a Lemon Drop.
- The Drive knob sets the amount of overdrive. Whether I was using single coil P-90s or humbuckers, I was always hearing a bit of grit, even with this knob at its lowest setting. If you want totally clean sounds, just roll off the guitar's volume a touch, and it cleans up completely, but still retains the unique treble bark and bite of the amps. At the other end of the dial, the sound is quite heavily overdriven - almost fuzzy, so you've got quite a bit of range to work with.
- The Tone control is a little unusual on this pedal compared to many overdrives, and very versatile. It adds treble as you turn it up past the midway point, and at higher settings also cuts bass. The opposite happens at the other end of the dial, giving you thicker, bassier tones. I generally preferred this control set to about 6 or 7, which seemed to be the closest setting for many classic Beatles-type tones.
- The internal construction is first rate. Perfboard mounted on two metal standoffs is used for the parts layout, and high quality components (including Switchcraft jacks, 1% metal film resistors and Sprague and Philips/BC Component capacitors) are used throughout the pedal. The interior is neat and clean, with expertly done hand-wiring and soldering. You won't find a cleaner, more well-constructed pedal anywhere.
- The input and output jacks on the review ZII are top-mounted, which means you can set it right next to another pedal without the jacks getting in the way. While I didn't have a Lemon Drop version available for the review, photos show them with side mounted jacks. You can order the pedals in either a 1590B sized enclosure with the jacks top mounted, or in a 125B sized enclosure with side mounted jacks, as depicted in the Lemon Drop photo below. Lumpy's Tone Shop also offers the purchaser a selection of 14 different powder coat colors for the Lemon Drop too.
- Switching is true bypass, and an orange LED illuminates when the pedal is active.
- Four clear rubber feet come pre-attached to the bottom of the pedal.
- The Lemon Drop / ZII can be powered by a 9V battery, or by an external 9V DC power supply. No adapter or battery is included with the pedal, although they do include a nice drawstring cloth bag for storage inside the box. The battery compartment is accessed by removing four screws and the bottom plate of the pedal. The power supply jack is located at the top of the pedal, and uses the industry-standard 2.1mm center-negative plug format.
- While versatile, the single tone control can make getting just the right balance of treble and bass a little bit tricky since it adds treble as you turn it past noon, and bass when you set it below noon. If you're willing to pay for it, and wait a little longer for a custom build, Lumpy's Tone Shop can build you a four knob Lemon Drop / ZII with a second EQ control.
- The Lemon Drop / ZII won't always get you all the way to Zep-land or Pepperland on its own; it lacks the onboard reverb and fuzz of the 7 series amps, and part of the recipe for those classic sounds includes contributions from the recording gear and acoustical environments of the studios they were recorded in, but those elements can be reproduced with other, fairly readily-available means in most home studios these days. The actual timbre of the 4 and 7 series amps, and the unique overdrive they're capable of creating, have been much harder to recreate - until now. The Lemon Drop and ZII make that issue a thing of the past.
I've got a whole lotta love for this pedal. Okay, I can hear the groans from here, but if the sound of that legendary riff rocks your world, then you'll definitely want to get your hands on a Lemon Drop / ZII. Add a bit of reverb and it nails that sound. Similarly, I was astonished with the number of mid-60s era Beatles tones I was able to coax out of the ZII when I ran a Gibson SG and an Epiphone Casino into it. The Lemon Drop / ZII is a must have for lovers of Beatles, Stones and Zep tones. Paperback Writer has long been a "holy grail" guitar tone for me, and one I've tried fairly unsuccessfully to replicate to my satisfaction for years, and short of a vintage VOX amp, nothing I've tried previously has been able to nail it, but the Lemon Drop / ZII does. That alone made it more than worth the very reasonable price. If you're a Beatles fan or Zephead, or just love those classic rock tones, you definitely need to check this pedal out. In a world of me-too pedal designs, it offers something that's different than any other pedal I've tried, and it is very, very cool. It is a real winner!
Lumpy's Tone Shop Lemon Drop ($129.00 plus shipping, available direct from the manufacturer)
Lumpy's Tone Shop ZII ($99.00 plus shipping "sale price", available direct from the manufacturer)
Lumpy's Tone Shop website
Phil O'Keefe is a multi-instrumentalist, recording engineer / producer and the Senior Editor of Harmony Central. He has engineered, produced and performed on countless recording sessions in a diverse range of styles, with artists such as Alien Ant Farm, Jules Day, Voodoo Glow Skulls, John McGill, Michael Knott and Alexa's Wish. He is a former featured monthly columnist for EQ magazine, and his articles and product reviews have also appeared in Keyboard, Electronic Musician and Guitar Player magazines.