Neo Instruments Mini Vent for Organ

The sound of the Hammond
For me the Leslie speaker sound is a large part of what we think of as the classic Hammond sound. The inventor of the Hammond, Laurens Hammond, disliked immensely Don Leslie’s rotating speaker design and refused to sell it in Hammond dealerships. It soon became apparent that customers thought differently and it’s now hard to imagine a Hammond without the Leslie. Hammond even started to include built in Leslie speakers in their later models. The classic Leslie design consists of two rotating units. A rotating horn is fed by a compression driver and the rotating baffle by a 15″ speaker crossing over at 800hz. Amplification is either valve or solid state and whilst the valve model is seen as the classic sound Leslie managed to create something special with their solid state amplifiers.

The rotors spin in opposite directions and run at slow and fast speeds with the treble rotor getting up to speed before the bass rotor. It’s this slow chorus sound and the ramp up and down that gives us the classic Leslie sound.

There are a few problems when gigging with a Leslie – it’s big, heavy and needs micing up quite a bit of the time. So for years manufacturers have tried to come up with small solutions that emulate the Leslie and these have varied wildly in application – from actual rotating speakers to rack mount effects to stomp boxes. Some have been very good and some really awful but none have quite nailed it. Enter Neo Instruments.

The Ventilator
In 2009 Neo introduced the Ventilator. A modelled Leslie 122 in a box that looked very similar to the old Boss Chorus Ensemble. It offered complete control over speed, drive, mic distance and acceleration and could be controlled either by the footswitches or external devices such as the Leslie type switch. The reviews were unanimous – here was a Leslie emulator that was good enough to replace the Leslie on stage.  However the Ventilator had a high price tag which competed quite closely with a real Leslie or a Motion Sound equivalent.

Mini Vent
In 2013 Neo introduced the Mini Vent which had the same guts as the Ventilator but in a smaller, less configurable package. It’s available in two version – Organ and Guitar. The guitar version lets you disable the cabinet simulation and is optimised for a guitar level signal.

The unit is a small but very solid pedal which feels and looks as though it can take a fair bit of punishment. There are no controls on top, just two foot switches. The Mini Vent takes a mono signal in and has stereo out. This could be an issue if you have a keyboard with only one stereo out and running everything through the Vent. There is a push button on the back which switches between two user definable configurations. Unfortunately power is from a 12v wall wart, and not a very substantial one at that. LEDs above the switches indicate the mode and rotary speed.

So with no controls what can you do with it. Well the Mini Vent can be programmed using the foot switches. It involves a bit of tap dancing but you can configure the drive level and mic distance and save it to either the A or B preset. All other settings such as speed, balance and acceleration are fixed. Sounds limited? Well you can’t adjust these on a real Leslie. The only thing that’s missing is the option to plug in an external control to switch the speeds but there is an option, although not inexpensive (see end of review).

One word of warning when powering the unit up. There is an actual relay that controls the bypass and it can give a bit of a thump if your speakers are turned up. I always turn the Vent on before the amps.

The Mini Vent emulates the later three position Leslie switch whereby you can have Slow, Fast and Stop. Stop is not like bypass – the signal is still running through the amp and speakers. In order to engage stop both the Bypass and Slow/Fast switches have to be pressed. I struggle a bit with the switches – they don’t latch down and sometimes it’s a struggle to switch between speeds. I’ve found the best technique is to rest my foot on the switch and use it almost kill a sustain pedal.

The sound
So how does it sound? Out of the box it sounds superb with just about anything I put through it. The ramp up and down is frighteningly accurate and the amp/cab simulation is superb. It really does sound at it’s best when running in stereo although for live I run mono into a Roland KC550 and it sounds fantastic. The drive works as it should – more level in, more drive out and it gives that authentic Hammond/Leslie growl. If you’re using a variety of modules and keyboards then I suggest putting a volume pedal before the Vent so that you can control the drive. As with a real Leslie the Vent accentuates the high frequencies so you may want to dial these back a little on your sound generator. Also the Vent can be a little noisy – you get that Leslie swooshing sound when at rest. I get this with my Leslie as well so if you want accuracy the Vent has it!

The Mini Vent can take any very average Hammond sound and turn it into something quite special. I’ve put a variety of modules and clones through the unit and even my Hammond – the results are superb and you can hear the before and after in the sound files at the end of the review.

So what are the downsides? On the sound side – nothing. What I really miss, as mentioned previously, is a remote jack so that I can use a Leslie type switch. There is a solution available from Ashby Solutions at a cost of $70 that replaces the bypass switch with a jack socket. If you’re not in the USA then Ashby will only allow the switch to be fitted by Neo dealers/distributors. The only place I could find to do it was Neo themselves who gave a price of €60 plus shipping to carry out the mod. If you already own the Mini Vent then it’s worth doing but if you’re looking to buy then the price difference between the Mini Vent + mod versus the new Ventilator 2 is around €20. For that difference buy the Ventilator 2 with all of it’s additional controls.

Since the Ventilator was release a number of new hardware emulators have come onto the market – the most notable being the Gsi Burn. However as far as I’m concerned the Ventilator line absolutely nail the 122 sound and there is no need whatsoever for me to look at anything else. It’s a Leslie 122 that fits in your pocket.

Neo Instruments Mini Vent – 



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