For over a year I thought something was wrong with my guitar cab IRs when I played direct into my DAW. My setup is a bunch of pedals going into my audio interface like this:
IR Loader in DAW <-- USB Interface <-- High Gain Pedal <-- Boost Pedal <-- Tuner <-- Guitar
Yes, I play with no power amp, real or simulated, although I'm told a tube power amp is used to generate most guitar cab IRs, so maybe I get some tube sauce for free there.
Symptoms
- IRs sounded like they had too much room sound. As if they had a small ambient room reverb on them. Like how I'd imagine it would sound if you mic'd an amp from too far back. You do you, but for high gain I want my mic'd sound pretty dry.
- Sometimes my high gain tones sounded spitty and gross. I couldn't dial out the fizz and crackle without losing the whole top end. Sometimes it verged on unplayable.
- One week or one session things sounded great, the next week I thought I was crazy to like that sound. That's normal for me, where one day I think a tone is perfect and then next I dislike it, but this was nuts.
- I thought I was going crazy.
- I thought...maybe IRs are overhyped bullshit?
- I thought...maybe there is something wrong with my pedals?
- Then the other day I suddenly realized that I could not get the sound in my phones to sound like the sound that was recorded in the DAW. This should not be the case ever. I was supposed to be hearing 100% DAW playback sound from my interface, in both my phones and speakers - the same sound that is recorded in bits and bytes.
Cause
- The mixer knob on my audio interface had always let a tiny bit of direct sound into my phones/speakers, even when I had it turned all the way to "Playback". I knew this all along, but I didn't think about it, because I am a dumbass.
- The way I knew this was: with the guitar track record button turned off in the DAW, if I turned my phones up loud I'd hear a bit of high gain junk when I played. It sounded like an industrial guitar track. I figured, that's weird...but how much can it hurt?
- A lot. It can hurt a lot. It can make you think that IRs are stupid, when the entire rest of the world seems to like them a lot.
- This was especially apparent when I had my DAW session really quiet, which happens sometimes because I'm shit at gain staging, and I forget things. When that happens, I have to turn up my phones or speakers to compensate, and the proportion of direct sound to DAW playback sound would go up. It turns out that those were the really bad days.
Approaches
- Live with it. Gain stage my projects so that the proportion of fizzy direct sound is as small as it can be compared to the project level. Probably a good idea anyway? You tell me, but probably.
- Get a new audio interface and hope it didn't happen there. My current audio interface is very low end, and out of production, so I figured what are the chances this happens again? This probably would have been a good approach.
- Hack up my current audio interface with a soldering iron.
Solution
I chose approach I nearly always take: hack shit up with a soldering iron. I don't recommend this unless you know what you're doing, and are ready to replace your hardware if you break it. I came so close to breaking mine.
- I took the interface apart. Lots of screws holding in the mic/instrument combo jacks and MIDI connectors, nuts holding in the pots and 1/4" jacks, and a single riser board for the top set of pots. This part was easy and fun.
- I located the stereo B10K pot, and discovered it is a standard voltage divider. If you don't know what one of those is, you can stop now. I sorta know what a voltage divider is. That gave me incorrect levels of confidence.
- Turned it all the way up to "Playback" and found it was 1.6 ohms on one set of legs, and 10K on the other. Voltage divider? I decided it is. What else could it be, it's a mixer pot? Right? I'm probably wrong.
- Got the pot off the board. What a nightmare. I am terrible at desoldering parts that have more than a couple of legs. My solder sucker is half broken, the tip is all melted and fuzzy, I can never get solder wick to work, my hands are shaky, and I'm just terrible at this. I ended up literally destroying the pot with a pair of nippers and pulling the chunks of plastic off the board, leaving only the legs. I was able to get the legs out by applying heat and pulling with the needle nose pliers. I mostly didn't scrape any board traces by accident. Mostly.
- I soldered the 1.6ohm set of through holes to short them out using clipped off leads from an old resistor, and left the 10K stereo set open.
- Apparently I didn't cut any traces or chip any important surface mount resistors.
Results
- Now, when I have my DAW record button off, and my monitor level all the way up, and playback is stopped, and I hit the guitar strings, I hear literally nothing in the phones or speaker. You obviously want to watch your ears doing this, and make sure you turn in back down fast.
- My IR setup sounds the way I imagined it should - very dry, no fake "room sound" effect.
- My guitar tone sounds the way I imagine it should - no industrial guitar fizz, unless I put it there on purpose.
- I feel stupid, but I'm recovering slowly.
- I didn't get an excuse to buy a new audio interface, which is a bummer because I am am a monkey that likes shiny new things, but good because the fun wears off on those even quicker than most gear.
