5f6-a-decimator-and-lentz-002 The ISP Decimator pedal does absolutely nothing to affect your guitars natural tone while engaged. So then why would you want to use a pedal that does not affect your guitar’s tone you may ask (that’s what pedals are for). The answer is simple- Noise Reduction! The Decimator pedal is not a noise gate it is a low level downward expander so noise is not just “clipped off” or muted when you stop playing like a typical gate, it is reduced while you are playing as well. This makes a huge difference in the quality of the overall sound of your rig. In this sense your tone is sort of affected by allowing the clarity and sustain of your notes and chords shine through. The technology of the Decimator is patented and state of the art in real time noise reduction. Because of this advanced technology the system is immediately responsive to very short-term staccato notes (think Dick Dale friendly) so there are no tracking issues. The advanced technology also provides a very slow, smooth, “ripple free” control of long sustained notes resulting in a very natural, unaltered tone.

On the Bench: The ISP Decimator looks to be very well built and is aesthetically pleasing. The sweep of the Threshold knob is smooth and the LED is bright to see on a dark stage. Switching is silent and you can use a 9v battery or 9v negative tip supply.

In the Shop: The test guitar that was used guitar was a Scott Lentz T-type guitar with traditional single coil pickups. No stacks or humbucking design type. The body is swamp ash with a one piece maple neck.

The test amp was a 5F6-A Bassman clone using Mercury Magnetics transformers, Sozo caps, carbon comp resistors, a Larry Rodgers tweed covered pine cabinet and 4- Weber VST, 10A125 speakers. Current production Sovtek 12AX7LPS’s and Tung Sol 5881’s were used and the GZ34 was an N.O.S. General Electric. The amp was hand built by me here at 300Guitars.


The Lentz T-type was plugged into the Normal channel of the amp with the Volume at 12 o’clock, Treble 2 o’clock, Bass 9 o’clock, Middle 2 o’clock and Presence at 2 o’clock. The Decimator was first in the chain of pedals which were in order: ISP Decimator, Analogman Juicer, RMC Picture Wha, Blackstone 2SV3 Overdrive, Demeter Tremulator, Analogman Chorus, Maxon Analog Delay and Boss Tuner.


Without the Decimator engaged and the Lentz T on the bridge pickup the guitar and amp sounded great. There was a little background hum as to be expected with a straight single coil pickup. With the Blackstone engaged on the Red channel the tone was great. Thick and fat with nice clarity but along with the gain of the Red channel came the noise. The typical single coil noise you get with an overdrive pedal. The noise was more apparent on long sustained notes as they decayed and faded out and on lighter played passages where you want to work the dynamics of the amp and pedal. Now with this starting point the Blackstone was switched off. The Decimator was then switched on and the Threshold set just at the point when the noise was gone which was about -45db. All background noise was gone and the sound of the guitar was surprisingly the same just without noise! As fast as I could chicken pick the Lentz T the Decimator would keep up and hard hit chugging rhythm chords sounded clear and defined. At this point it was time to try the Blackstone with the Decimator. With the Blackstone engaged and not playing a note the rig was dead quiet. It was almost as if the amp was on standby. I hit an open “A” chord and there was the sound of the Lentz T and the 5F6-A pure and unaffected because of the reduced noise. All you heard was the pure “keraaang” of tone. Single notes sang and sustained and the tone actually sounded more pure because of the reduction of the noise. This was great! I could use a single coil guitar without the noise and not affecting the tone.

On the Gig: For clean playing in a very noisy venue with dimmers and other electrical issues the Decimator helped to keep the noise to a minimum. With the Blackstone engaged the noise was still suppressed and there was a very noticeable difference with and without the Decimator. In a sort of more “normal” type of venue where there were no dimmers or electrical issues the Decimator helped keep the noise very much under control and it was hardly noticeable especially when the band was in full gear. On slow blues and ballads it also helped keep things quiet and the single coil pickups on the Lentz T sounded richer because of the lack of noise.

Final Analysis: The Decimator is simple to use (one knob) but cleans up the noise, hiss and any buzz or hum in your signal. In the noisiest clubs you can use your vintage type single coil pickups with minimal hum and noise. Guitars with humbucking pickups are literally silent. ISP recommends that you put the Decimator as the last pedal in your chain but I had better results with it being first in the chain.  List price is $149.00 and retail for about $125.00 from such places as Musician’s Friend. Let your tone shine through by destroying noise with the ISP Decimator.