Cave Passive Pedals Grunt


Cave Passive Pedals



It has the ability for you to choose either “Clean” for frequency boost or “Dirty” for an outrageous 60's sounding overdriven bass amplifier.

Should work fine before or after other "Powered" pedals.

review by Mark Deayton

Recently I came across the some interesting eBay listings for guitar and bass effects pedals that operated without batteries, or for that matter, external power either. The seller, an Australian company called Cave Passive Pedals, describe their range of pedals as totally passive - no power source required.

I frequent several guitar and bass related online forums on a daily basis, and at two popular Australian-based forums interesting discussions began to develop about these pedals, so I decided to contact Cave Passive Pedals myself and find out more about their products. At that point in time there were no audio samples available on the Cave Passive website (unlike now, where there are numerous sound files demonstrating how these pedals perform), so I asked if it would be possible to hear audio samples. I explained that I was aware of the pedals generating a lot of discussion among the potential audience for this type of product, but in the absence of audio samples many guitarists remained sceptical.

I immediately received an email reply from Heath Cave himself, who provided some background on himself and his business, explaining that he is "a professional musician and electronics engineer so I combined the two as I found a definite need for good sounding pedals without the hassle of a power source". Heath said he would mail me an audio CD with sound samples. The day the audio CD arrived, Heath emailed me to let me know that he had also posted me a "Grunt" pedal for me to review.

The samples on the CD that have since been uploaded to the Cave website were enough to tell me that the Grunt pedal was not a gimmick, so I was looking forward to test driving one in the flesh.

The Grunt pedal arrived in a very nice hand made MDF box with a sliding lid, which Heath explained was normally used for the deluxe pedals in the range. The box itself gives the product the type of boutique look that appeals to pedal geeks, and would be a useful marketing tool.

The Grunt pedal for bass is a boost/overdrive effect in a small aluminium Hammond kit box, finished in thick glossy white duco. Initial impression is that the pedal is solid enough for professional use and looks the part as well. The Grunt is a very simple pedal, with a two position selector pot in addition to the footswitch and input/output sockets. I did sneak a look inside and saw that the main circuitry is fully enclosed in silicone, presumably to make reverse engineering difficult, but would also mean that troubleshooting and repair (if needed) might be just as difficult.

The two positions on the selector knob are labelled "Clean" and "Dirty", so you need to choose the setting you want before stomping on the footswitch to engage the effect. It really is a simple pedal, that performs in a slightly different way depending on how hot the signal level is that you are feeding it with.

For review purposes I tested the Grunt pedal on several different basses with the volume control on each bass set at maximum, and with my bass rig's preamp (Alembic F-1X) tone controls set flat. The basses I used were a Nash PB63 Precision with vintage spec Lollar pickup, a Nash 51P with a high output Duncan single coil, a Musicman Stingray with the standard active humbucker, and a Gibson SG Reissue with the beefy TB Plus humbucker.

Results with the Grunt pedal varied quite a bit from bass to bass, but not in an unsatisfactory way at all.

Let's start with the Nash Precision, which has a pickup output that I'd class as "standard" in terms of passive basses. With this bass, the Grunt pedal operated exactly as advertised - virtually identical to the audio samples on the Cave website. With the selector on the "Clean" setting, kicking in the foot switch gives a warm and full boost to the signal, with overtones of an old school tube amp. With a Precision, Jazz or most other passive basses equipped with standard output pickups you could use this setting as either a boost for solos, or leave it on all the time to give your tone some warmth through a solid state amp.

Switch to the "Dirty" setting, and you get a slightly fuzzy, overdriven sound reminiscent of a lot of records you listened to when you were a kid in the 1960s. On the Precision the Dirty setting is the same volume as the "Clean" boost (ie. there is no volume drop that I could detect at all), but the Dirty setting isn't as full and warm as the Clean boost, so at first listening it does sound thinner (bear in mind that this review was conducted at living room volume, not gig volume).

Each of the other 3 basses I used while I test drove the Grunt pedal have higher output pickups than the Precision, so the Grunt pedal performed differently with them - in a good way. With a stronger signal going to the Grunt's input jack, the Grunt's output was transformed into a pretty good approximation of an overdriven Ampeg SVT, which is the bass tone that a lot of bass players have inside their brain as the sound they desire. Don't get me wrong, this pedal certainly doesn't have the nuances and flexibility (or price tag) of say, a Sansamp Bass Driver pedal or a Line 6 VT Bass pedal - both of which can carbon copy an overdriven SVT - but the Grunt is pretty close, especially if you are giving it a hotter signal from your bass (or other pedals in your signal chain). With the Gibson SG Reissue, Musicman Stingray and the single coil '51 Fender style bass the tone while on the "Clean" setting was classic creamy Ampeg tube amp, and when the Grunt's knob was flicked to the right the "Dirty" setting resulted in the instantly recognisable crunchy overdriven SVT sound that will make many bass players, both young and old, salivate.

With the higher output basses the "Dirty" sound was fuller than it had been with the Precision, but was never harsh or biting. Both the Clean and Dirty tones are very useable, whether for a solo boost or left on all the time, depending on the style of music and your preference for getting dirty.

The Cave Passive Grunt pedal is well suited for bassists who play classic rock, blues, grunge, punk and, I dare say, even metal. At well less than half the price of a Sansamp BDDI, VT-Bass or other similar sounding overdrives and having a smaller footprint too, the Grunt represents great value, and the fact that no battery or external power source is required means that it's a very portable and quick to set up piece of gear to enhance your live or recorded tone.

The idea of powerless effects pedals is a good one, especially for musicians who regularly find themselves on small stages where running power to effects is cumbersome, or for bands playing a multi band night where fast changeovers between acts is the name of the game. A pedal such as the Cave Passive Grunt would also be an asset on a pedal board where real estate is at a premium, given that no power lead is required and the pedal itself has a small footprint.

There is a downside to passive pedals though - there is no LED to show when the footswitch is on. Many gigging musicians tend to rely on LEDs on pedal boards to know which effects are engaged, especially when multiple effects are being used at the same time. The lack of an LED would certainly be inconvenient for some guitarists and bass players, however this is the only negative I can find with the Grunt pedal.

All in all, the Cave Passive Grunt pedal is a nice looking, quality built overdrive pedal in a sturdy road-worthy enclosure, with boost/overdrive tones that are extremely usable for gigging and recording purposes. If you are looking for the classic sound of an overdriven tube bass amp, the Grunt can do this for you, although you will need to be content with having just two settings at your disposal, and be able to survive without an LED to indicate when the foot switch is on. Of course, you won't ever have to buy batteries again nor need to connect the Grunt to your pedal board power supply, and it takes up no room at all on the board. On balance, the pros outweighs any cons with this pedal, especially at the very reasonable retail price.

review by Shayne Spencer, bass guitarist of "Powerlines"

As a bass guitar player it is important that I find the right sound. Using the “GRUNT” pedal from the CAVE PASSIVE PEDALS range, I am able to use a powerful bass sound with the “Dirty” and “Clean” boosts given by the pedal. The fact that it is “Passive” is what sold it for me, as I have had trouble with wires and batteries in the past. I found the “GRUNT” pedal does NOT weaken the signal or drop in volume. I use an Epiphone Thunderbird and Fender Jazz bass through a simple bass amp and while using both these guitar this pedal does not change between them, always giving the boost and rich overdrive sound.

Another great pedal from their range is the “FURRY TONGUE” which really helps boost the bass sound and I am able to get an amazing amount of power in the low end out of it. I can also get a huge scope of different sounds and tones out of this pedal.

The fact that these pedals can be used together is also a bonus and gives the sound a very powerful boost without dropping the volume at all.

These pedals are great, they are passive, compact, well presented, and very user-friendly.

Definitely great examples of intuitive design and value.

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