You know your analog amps. You’ve grappled with digital models. But let’s investigate an approach that isn’t strictly analog or digital, but a marriage of the two technologies.
Amps and models sittin’ in a tree. Most amp modelers mimic both the core amp sound (through varying combinations of distortion, compression, and EQ) and the character of the speaker, cabinet, and mic (via an EQ setting based on the modeled components, or, more often, an impulse response recorded through the modeled speaker and cabinet). While we can argue endlessly about the accuracy of amplifier models, it’s hard to deny that good speaker/cab impulse responses are shockingly realistic. So let’s see what happens when we combine a line-out signal from an analog amp with modeled speakers, cabs, and mics.
How to destroy an expensive amp. Easy! Just disconnect your speaker and try recording from the speaker-out jack. If you’re blessed with luck and a good nose, the aroma of frying electronics will prompt you to abort before you do permanent damage. If not, better switch your wallet off standby.
Analog amps must always be connected to a speaker—or to a component that dupes the amp into thinking it’s connected to one. Load boxes and speaker attenuators do this very trick. These devices usually have both speaker-out and line-out jacks. You use the former to connect back to your speaker/cab, often at an attenuated level to achieve loud-amp tones at listenable volume. Meanwhile, the line-out conveys your amp’s pre-speaker sound at a level suitable for recording inputs. (If your amp has a dedicated line out, great—no load box needed, provided you’re still connected to a speaker. But most vintage and vintage-style amps don’t.)
Load-box terminology can be confusing, but a recent Tone Tips column by PG’s Peter Thorn (The Lowdown on Load Boxes, Attenuators, and Reamps, May 2015) deftly decodes the lingo. For our purposes, you need a box with a line-out jack and no built-in speaker emulation (or emulation you can switch off). We’ll mimic the speaker in software.
So dry, you’ll cry. For these recordings I used a Swart Night Light attenuator/load box (Photo 1). (It’s a nice device at a good price, but it has many rivals with near-identical functionality.) I plugged into a homemade germanium overdrive and a small Divided by 13 CJ11 combo, running the direct signal into Logic Pro, my DAW of first resort.
The result (Ex. 1) sounds dreadful. All that death-ray treble and nose-punching presence? They’re precisely the frequencies that guitar speakers typically filter out.
Next, I inserted Amp Designer, Logic’s amp-modeling plug-in. Amp Designer doesn’t let you use speaker models without an amp model, so I dialed up the transparent preamp setting, a neutral sound devoid of guitar-amp coloration. I added speaker emulation, and suddenly this sounded an awful lot like a miked amp (Ex. 2). I chose a model derived from an ancient Fender 10" speaker (Photo 2) and added a touch of humble home-studio reverb.
Compare that to Ex. 3, the same recording through a modeled mid-’60s Marshall 4x12 (Photo 3), this time with expensive-sounding plate reverb. Can you see how this method might provide vast sonic variation without relinquishing your core amp color?