The latest rage in guitar equipment is amp modeling.  Not too long ago, I profiled some emulators I use in my studio column.  Computer technology is allowing manufacturers to digitally simulate the sounds and characteristics of many classic and expensive guitar amplifiers and then place these tones into one convenient amp or rack device.  The benefits are that the guitarist can carry one portable unit which emulates the tones of many heavy and sometimes expensive amps without spending a ton of money or exposing potentially rare equipment to the rigors of use.  Most modeling processors are optimized for recording directly to mixing boards so that amps don't need to be used.  Aside from the convenience issue of not having to carry an amp, recording or live performing directly to a mixer can significantly cut down on noise levels in the studio or onstage.

It seems as if most amplifier and effects companies are offering modeling devices of some sort.  The leaders of this technology are Roland, Line 6, and Johnson.  I have personally used a number of modeling products for different applications and feel that there are pros and cons to how they perform.  It is important to keep the whole concept of amp emulation and the laws of physics in perspective.  Nothing works as well for me as a tube amp cranked up and pushing air through real speakers.  Nevertheless, if I approach modeling products with the proper attitude and cognizance of their inherent limitations and benefits, then I find that I am not disappointed by unrealistic expectations.
 
 

I will give an example here of  keeping a realistic perspective on the performance of amp emulators.  I have a Line 6 POD Pro rackmount unit in my studio.  I think it is a fine unit and sounds really good.  It offers 16 basic amp models and various effects such as chorus, delay, tremolo, etc...to process the sound if desired.  Some of the amp models include tones based upon a Matchless Chieftain, Budda Twinmaster, 1965 Fender Twin, and Dumble Overdrive Special.  I have been fortunate to play all of these amps and most of the ones emulated by the POD.  In most cases, the POD will provide a reasonable simulation that is in the ballpark of the originals.  What the POD can't do is replicate the immediacy and feel of playing the originals in a room through speakers.  Even using their modeling amps with actual speakers such as the Flextone series, it's a stretch to expect a dead-on recreation because different amps have different speakers, and a modeling amp comes equipped with only one pair, which must be used for all of the emulations.  Furthermore, the signal monitored through headphones and/or a mixing board will sound relatively different than the original, unless we are speaking about how the original would sound miked and run through headphones or a mixing board......and this is where I think the emulators should be judged.

At other locations on this site, I have shown some audio and sound clips of a Dumble Overdrive Special amp that I've been lucky enough to play, as they are very rare and feature incredible tones.  Line 6 could protest this all they want, but I promise you that the Dumble setting on the POD does NOT sound like that amp does being played through a 4x12 Marshall cabinet at live volume.  However, even a real Dumble OD Special would sound different if miked and run through a mixing board.  We are now inserting microphones and boards into the tonal equation.  I think that the amp modeling companies are trying to simulate how the original amps would sound when they are miked.  In that regard, I think that the Line 6 does a very commendable job for the price.

There is another practical application for amp emulators that I have learned to appreciate over the last few years.  I live in an environment where noise levels are a concern.  Guitar amps can get pretty loud and I go to great lengths to makes sure that my neighbors are not disturbed at inappropriate hours of the day, or night as the case may be.  One never knows when inspiration will strike, and it is necessary to feel free to create whenever the muse calls without being limited by concerns of disrupting the people living next door or even in the same house with you.  The POD allows me to record or rehearse in my studio late in the evening or early in the morning without other people hearing it.  I can be blasting away in my headphones at 3 AM  while everyone else is asleep.  If I would prefer a track to be recorded with an actual tube amp, I can always lay the scratch track down with the emulator and go back at a more reasonable time the next day and do overdubs with the desired gear.

The Line 6 Bass POD and Bass POD Pro are the first units geared to replicating established bass amps.  In some ways, I think my Pro unit has been an even more useful addition to my studio than the guitar POD.  Getting great bass tones to tape has never been easier than using the Bass POD.
 

Modeling Pedals:

Like guitars and amps, effects pedals have been around for a number of years.  Some have even attained vintage status.  Pedals come in a variety of shapes, sizes, and sounds.  There are analog and digital pedals.  Some units even use tubes!  While most of today's pedals are influenced by earlier designs or, in some cases, direct copies of effects from years gone by; there are a few which use current advances in technology to present  new concepts in processing.  Ironically, Line 6's new modeling pedals use the company's modern emulation technology to recreate beloved boxes from the past.  Just like their modeling amps and PODs, the mission is to conveniently place a number of replicated products into one unit.  There are a lot of manufacturers simulating amps, but very few modeling classic stomp boxes.
 
 

Even though Line 6 is using digital circuitry to achieve this magic, it is important to note for the purists out there that these pedals seem to be very serious products with a heavy-duty build quality and true bypass.  There may be some players who will instantly dismiss these units, especially if they are biased against the PODs and other products in the Line 6 stable.  I encourage people to look at these modelers a little differently than the amp emulators because, from what I've experienced thus far, you can run these effects into your amp of choice (tube or solid-state) and achieve some very useful and decidedly musical tones.

I first became aware of the above pictured DL-4 Delay Modeler when speaking to a guitarist touring with a legendary musician.  He had nothing but wonderful things to say about this device.  Since he plays through a lot of boutique gear and is a very strong player, I put a lot of stock in what he had to say.  Upon acquiring one of the delay units, I confirmed that this pedal is definitely a professional piece of gear capable of providing about any kind of delay texture imaginable.  Everything is quiet and I like the fact that the user can program three presets for quick accessing.  Perhaps the most useful function of all is the Tap Tempo button, which allows the user to sync delay times up with the drummer live on stage, or in the studio.  There is also a 14-second phrase sampler onboard providing hours of fun!  If only something like this was around when I started playing guitar!
 
 

I currently own lots of pedal effects of all types and ages.  I must say that I am impressed thus far with the new Line 6 DM-4 Distortion Modeler.  My experience with it to this point has been studio use.  I anticipate taking it out to a live performance in the near future.  This box features patches based on such notable units as the Ibanez TS-808 Tubescreamer, Chandler Tube Driver, ProCo Rat, Arbiter Fuzz Face, and Tychobrae Octavia among others.  The user can program four convenient presets accessed by the true bypass footswitches.

As with any effect, I find that there are some settings that I like better than others.  The DM-4 is able to produce some very harsh and saturated sounds that don't always fit into my playing style; but it is nice to know that they are available in addition to the very warm and analog-like tones offered by this box.  While I am still using other distortion and overdrive pedals for the bulk of my live shows, I have yet to see any other box packed with such versatility as the DM-4.  It is truly an excellent box.

Another emulator worth mentioning is the Line 6 MM-4 Modulation Modeler.  The MM-4 models choruses, phasers, and tremolo units.  I don't currently own one of these, but did find them to be of the same quality and value of the other modeler pedals by Line 6.
 

The Bottom Line:

First of all, I have not intended for this article to be an endorsement of Line 6 products at the exclusion of other brands.  There are a number of other manufacturers making similar products of comparable quality.  My personal experience has led me to purchase the aforementioned emulators, and I feel that Line 6 stands at the forefront of modeling technology at this moment.  I am also impressed with Roland's implementation of virtual modeling into a number of their products.  That said, there are also some companies whose products suffer by comparison.

My personal opinion is that modelers in general are not developed enough yet to completely make good old tube amps and vintage effects completely obsolete.  As I said earlier, if you can keep it all in perspective and understand that modelers do offer some very practical benefits despite their deficiencies, then they can represent a remarkable value in processing power and sheer flexibility.

The main drawback I notice about modelers has to do with "feel".  There is a certain feel to playing a tube guitar amp that just hasn't been recreated completely by digital technology today.  The emulation products are improving dramatically, so perhaps there will be a day in the near future when digital devices will faithfully replicate desirable amps and effects.

I would heartily recommend today's relatively affordable modeling products for beginning guitarists.  These units offer so many sounds that they can teach an inexperienced player about what is out there while only requiring the purchase of one box or amp.  If a player plugs into a modeling amp and dials in the Fender Twin simulation, he may find that he likes the way it sounds so much that he goes out and finds a real Fender Twin.  If these units had been available when I was starting to play the guitar, things would have been a lot different!

I still plan on using my emulators in studio situations for the foreseeable future because I think they feature some great tones that can be accessed without the struggle of hauling heavy equipment around or disturbing the neighbors.
 

Jason