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Diezel Schmidt Amp Review

Diezel Schmidt Amp Review

Blending vintage class-A British tones with modern feel in a heavy, rugged package

Download Example 1
Channel 3 - High Gain
Download Example 2
Overdriven with Reverb
Download Example 3
Clean with Reverb
Clips recorded with a 1978 Gibson Les Paul Custom. Clean clip recorded with a 2008 Fender American Strat with Lollar S Special pickups.
Diezel Amplification burst on the scene in 1994 with the mighty VH4 and VH4S amplifier heads, which caused a stir when Adam Jones of Tool embraced them as part of his triple-amp stage and recording rig. Since then, Diezel amps have found favor with players including Neil Schon, Metallica, Buckethead, and Weezer, to name a few. Diezel amps are known for their power and definition, along with their quick attack, extreme versatility and their ability to stand out in the mix. But the company’s most recent creation, the three-channel, 30-watt Schmidt, represents a deviation from its high-gain, fire-breathing brethren with a Class-A power section and more vintage-styled tone options.

Hefty Tone
If you’re in the market for amplifier that’s light in weight, it might be wise to pick up a Schmidt head before deciding to purchase one. The amp head itself weighs a little over 46 pounds, making it a bit hefty for loading in and out of gigs and studios. It’s only 13 pounds lighter than Diezel’s high-gain monster Herbert, and weighty enough to remind me of lugging around an old Ampeg SVT from the late ‘60s that I used to use from time to time. Regardless of weight, the amp head was quite handsome. Visually it has a lot in common with older Mesa/Boogie Mark series heads, with a tall, deep cabinet that’s still narrower than most full-size amplifier heads.

Simple is as Simple Does
The Schmidt is simple by Diezel standards. Three channels are controlled by two sets of equalization and tone-shaping controls, along with a lone set of gain and volume knobs that alter the third (or More Crunch) channel’s sound. The circuit itself is built around two totally independent preamps. The first channel is a straightforward clean channel, with controls for reverb, bass, midrange, treble, and volume. The second is for low to moderate high gain and features identical controls save for an additional knob for preamp gain. Finally, the third channel is built for ripping high gain tones. It shares the equalization section and reverb of the second channel, but has its own gain and master volume knobs to give the player the option to cut or boost the volume when the channel was engaged.

Each channel can be selected via a five-button footswitch, which also switches the effects loop and reverb effect. There are separate jacks for each channel, the reverb, and effects loop on the back panel of the amp if you prefer a simpler footswitch use channel switching on the fly less.

The Schmidt’s circuit is built around a quintet of 12AX7 preamp tubes and powered a Class A 30-watt output section, which is driven by a duet of EL34 power tubes. One of the coolest things about the Schmidt is that the power tube bias is cathode-based, meaning that a rebias is unnecessary when changing power tubes. What’s more, the Schmidt is capable of utilizing several different types of power amp tubes without the need for rewiring the circuit. If a player wants to trade out the presence-heavy midrange qualities of EL34 tubes for the glassy, cutting nature of 6L6s, it’s a matter of popping one set out and replacing them with another. The Schmidt will accept 5881, 6L6, 6V6, KT66, KT88, EL34, and 6550 power tube types.

The Best of Both Worlds
To tone-test the Schmidt, I connected the amp with a matching Diezel rear-loaded 2x12 cabinet, loaded with Hempcone 12-inch speakers. The cabinet itself features a pretty cool rear baffle design that enables quick conversion to a semi-open back design.

Grabbing a 2008 Fender American Stratocaster with Lollar Special S Series pickups, I plugged into the Schmidt and setup a basic clean tone with all equalization controls at noon and just a hint of reverb. The result was a tone that had the big, bold sound and feel of a healthy Vox AC30 mixed with Diezel’s trademark high-fidelity voicing. One of my favorite clean tones has been that of the first channel of my old Diezel VH4S head, and this little fiend topped it in terms of clarity, punch, and bite. The VH4S—and most Diezel amps, for that matter—had a very solid, firm low-end voicing that really didn’t have much “give” to it. The Schmidt had the same low-end massiveness as the rest of the Diezel family, but with a softer, more vintage vibe that seemed more like an integral part of amp’s tonal spectrum rather than a foundation. The EQ was exceptionally responsive. And increasing the treble control added the right amount of cut on the top end without hitting any ice pick frequencies. In terms of headroom, the Schmidt’s clean channel was second to none. This amp was very, very loud. And any player looking for maximum headroom with a warm, soft top end really will be at home with the Schmidt.

The Schmidt’s overdrive tones are also inspiring. I tried the second channel using a 1978 Gibson Les Paul Custom with Tom Anderson pickups. The Andersons have a very wide frequency range, which made them perfect for pushing the Schmidt’s second channel frequencies over the edge. Low and mid gain tones were classic Diezel, coupled with the softer low-end voicing you hear in the clean channel. With the EL34s in the power amp, the overdrive sounds had a very British quality about them, with punchy midrange, a round top end, plus the super-quick attack that is a hallmark of Diezel amps.

The Verdict
The Diezel Schmidt is a perfect blend of vintage, class-A British tone and modern hi-fi feel. The amount of clean headroom and punch is incredible, with overdrive tones that certainly live up to the reputation that Diezel has solidified with its past amplifier creations. And if you’re looking for the means the walk the line between those two worlds, the Schmidt should unquestionably be on your radar.
Buy if...
you’re looking to separate your tone from the pack with one of the most unique sounding combinations of vintage and modern sounds.
Skip if...
you prefer a lightweight amplifier, or one with more of a scooped high-gain voicing.

Street $4000 - Diezel -