15ips Archive: "Mixing"
About this time last year, I promised myself: No new equipment. I did fine, even with my compulsive window shopping habits, but I started to hit some frustrating limits with the equipment I’d chosen. Most of what I own is “good and cheap”, as cheap as used 1980s professional audio equipment can be, and while I have the basics covered pretty well I felt really limited in options during mixdown and especially while recording vocals. The only compressors I had were the dbx 166xl, which is a high quality, inexpensive compressor for percussive material but it’s absolutely terrible for vocals.
I have a very intimate understanding of my equipment (heh) and once I found out about the different types of compressors I realized what I needed. I set my sights high and I considered investing in “the lower high end” equipment but I just don’t have the money for it. So, I began a search for the missing link in my home studio, at a price that wouldn’t hurt my caboose.
I heard about the ART Pro VLA II maybe a couple of years ago and I initially dismissed it – I have an ART MPA Gold mic preamp that I’ve never been too happy with. I was a little shocked to read raving reviews in Tape Op last November, saying that it was a really good deal for the price. I decided I’d take a second look, and I’m really glad I did.
When researching modifications and upgrades (i.e. changing stuff) I started at this GearSlutz thread, which has a series of audio clips recorded through various configurations of stock and modified parts. It was pretty informative… I really liked the sound of the Mullard tubes. I decided to go all in, and I bought the ART from Musician’s Friend and bought a pair of Mullard ecc81/12AT7 tubes from eBay. The good thing about audio equipment is that if you don’t like something and can’t return it, you can always sell it to someone else…
I got the ART and the tubes on the same day. I tried the unit with its stock tubes (Ruby Tubes 12AT7) and I actually really liked the sound – it was smooth and accurate. It didn’t sound “cheap”, which is an instant win… in my opinion it beats a lot of products in this price range in regard to overall quality and the ‘musciality’ of its output. I quickly (carefully) opened the unit and installed the Mullard tubes, and tried it again. Wow!! This is not a silver bullet… but this is a fantastic combo, and the VLA is the right product for what I want. I feel an instant response when I twist the knobs, and it sounds really, really good when I really crank up the compression and add lots of post-compression gain through the Mullard tubes. So for… $360 total? This thing is an ace.
I realized that the Pro VLA II could also be used effectively as a low pass filter – with Mullard tubes it gently burns off high frequency detail over 16k. This can be compounded or affected in other ways by adding input and output transformers, just as the original poster in the GearSlutz thread did. The Cinemag transformers have a pretty severe HF roll-off beginning at 10k (!) (here’s the spec sheet) but it might be useful sometimes? I like the sound but I don’t want it all the time. I’m considering adding transformers and adding a toggle switch, to either use the transformers or bypass them, but I’ll leave good enough be for now. I just wanna make music, anyway…
Hey folks, I wanted to give a quick run-down of some techniques I’ve learned these past few months.
I’m spending a lot more time actually recording and mixing these days since my equipment is finally all up and running. Most of the time.
dbx Noise Reduction
Tascam owners, I’m looking at you. dbx noise reduction is a godsend for those of us using narrow format multitracks such as Tascam’s half-inch eight tracks (38, 48, 58, TSR8) and the 388. There are some caveats, though, and also some times when it’s best to bypass noise reduction on a particular track.
How dbx Noise Reduction works
dbx Noise Reduction relies on a compressor and expander to do its thing. The incoming signal – the signal which you want to print to tape – is encoded using compression and some EQ futzing. Common sense in using compressors also applies to using noise reduction: A quick jump in level will cause undesirable gasping/pumping and create undesirable artifacts.
I try to keep peaks at or below -3 dBu when using noise reduction. This allows noise reduction to work at its best. Pushing levels beyond -3 dBu will cause undesirable gasping/pumping sounds and may add extra high frequency hiss.
To NR or not NR
If you’re unsure about whether to use noise reduction, do a sample take and monitor on the playback head. While the take is running, switch NR on and off and compare the two. You’ll need to adjust the level of the signal before it hits the tape; get the peaks close to 0 or +1 dBu without NR and close to -3 dBu with NR. Folks using two-head decks like the TSR8, the MSR series, and the 388 will have to do a few test takes because these decks lack a separate playback head.
Do NOT use noise reduction with hand percussion!! Shakers, tambourines, claves, etc are notorious for creating transients and will always cause dbx encoding errors before the signal even gets to tape. You’ll notice “thuds” and “pops” on playback. With NR off, try to get the signal to peak around -6 dBu and let the tape’s natural transient-squashing abilities smooth them out for you. The tiny extra bit of hiss will dither the harshness of the instrument and make for a more pleasing sound, anyway.
Seriously, don’t compress bounce mixes. Compressing individual source tracks is OK, but don’t compress the whole bounce. Think about how it’s going to sound when those tracks get compressed AGAIN, because they will be compressed again in mixdown and AGAIN in mastering, if you take your mix to a mastering engineer. I learned this after a lot of heartache and after blaming my equipment for the thin, lifeless sound I was getting. Just don’t. Leave that shit turned off.
Monitoring The Bounce
Sort of like how I suggested you try a track with and with noise reduction: When bouncing your tracks down, monitor the new bounced tracks on the repro head and see how they sound. If you adjust the mix at all, you can hear the result instantly.
Don’t Erase The Source Tracks
I hate listening to a mix and realizing that the shaker/bass guitar/Yoko Ono is too loud. If you don’t erase your source tracks you can go back and do the mix over. You’ll need a second recorder to bounce your mix to (I use a half-track 1/4″ deck). Do your mix, shuttle the tape ahead thirty seconds or so, and record the bounced mix onto fresh tape.
Cut, Don’t Boost
Cutting frequencies, instead of amplifying them, creates a more natural-sounding effect. I resisted this advice at first but I’m really glad I came around.
Hi-Pass Filter Everything*
You really don’t need anything below 200 Hz except on bass guitar, piano, and percussion (hence the asterisk). EQ this stuff out, especially before sending it to a compressor. Lower-frequency signals will add extra level to your tracks and make compressing difficult, and unless you have a sub-woofer you’re not going to hear all of the low-frequency buildup over each successive track and bounce. Just cut it out at each step.
I’m leaving this part open for now, and I’ll add to this post later if anything comes up.