US-428 is a 4 x 2 interface. Wrong direction for you AFAIC.
I'd hold off getting dithered about why recordings are turning out as such until you get the machines calibrated.
What one for +6 tape? Understand that you can use
any calibration tape for calibrating to any tape type. "+6" means "I am a tape that distorts to 3% when exposed to 355 nanowebers of magnetic flux over a meter of tape." 355nWb/m is equivalent to "+6" at 1kHz.
Get your head around this for a sec...Calibration is all about "what does '0' on the VU meter mean, and let's get all channels/tracks operating the same."
The standard for "+6" tape is to set "0" to mean
250nWb/m of flux level...250nWb/m equates to "+3"...why do we want to set "0" to mean "+3" when you are using "+6" tape?? Because the "standard" is to have your meters tell you that at "0" you have 3dB's of headroom before you start saturating the tape to 3% distortion. Keep in mind that your program material doesn't typically sustain at 'X' nWb/m...its typically complex and all over the place, okay? But we are talking about a "calibration reference standard". So, okay...hopefully you now understand why the standard calibration tape for operating "+6" tape is a 250nWb/m test tape. No compensating has to be done. You reproduce the level set tone and anjust the trimmers so the meter reads "0".
Okay...let's say you don't mind, or rather LIKE the sound you get off of tape when its pushed to 355nWb/m...well if you calibrated the machine for "0" at 250nWb/m then you are going to want the VU's hovering at +3 instead of 0 when tracking. Does that make sense? And it works the other way too...let's say the machine is setup for "0" at 250nWb/m but you want clean-clean-clean coming off of tape and the program material has high periodic sustained transient peaks...then maybe you're going to set your levels so that the meters are hovering around
-3 to keep those peaks out of distortion. The downside is that now you're going to hear more tape noise during the amplitude valleys but you'll avoid saturating the tape on the peaks. Your
material and your
ears are the ultimate judge in HOW you setup your machine and WHAT kind of tape you use and HOW you use the tape.
NOW...let's say most of what you do is in the former category (i.e. you like what you are getting off of tape when you are pushing your nominal levels to +3...this is not normal BTW because remember that the meters are
averaging meters...they show the "average" level which means your transient peaks especially on stuff like percussive sources is likely to be WAY above +3 when the meter reads "+3", and you risk clipping the record amps and such...overhead is goooooood...but I digress...) and let's say you'd rather not have to deal with looking at +3 all the time and to have that room on the meters to see what is going to tape...IOW you want "0" to really mean 355nWb/m. Do you need to get a 355nWb/m test tape? Well goodness sake
no. During calibration instead of setting the levels to "0" on the VU meters when the test tape is reproducing the level set tone (typically 1kHz) you would set the meters to reflect
-3dB's. Think about that...if the 250nWb/m level set tone drives the meters to -3, then what are the meters saying if they are at 0?? Well they are saying "hey you're hitting me with the equivalent of 355nWb/m." (i.e. +6). Same test tape, any ol' operating level you choose.
This also means you can use a 185nWb/m test tape (which was the standard for +3 tape...zero the deck to +0 to get that 3dB's of headroom before 3% distortion) and set the deck up for any operating level...just changes the offset you use during calibration.
My recommendation is that you get a 250nWb/m tape. Its likely where you want to start and it is just easiest not to have to mess with offsets in the beginning. Tascam designed both the 38 and the TSR-8 for 250nWb/m operation...i.e. +6 tape with 3dB's of headroom before 3% distortion. Its what the amp electronics were designed for. Then later you can take it anywhere you want if there is something you are trying to achieve that you aren't getting with that setup.
Both the 38 and the TSR-8 are also designed around the IEC equalization standard, so if you are in the position to choose your MRL tape then that's what I'd get...250nWb/m, IEC eq, 15ips.
Subject for another day but you can ALSO use any equalization standard tape to cal to a different standard (i.e. you can use an IEC tape to set the deck up for NAB equalization and vice versa). You can ALSO use tapes of different
speeds to cal at a given speed (i.e. you can use a 15ips MRL to cal a 7.5ips machine).
There are limitations here though, and I will tell you that of these three areas (flux level, equalization standard, and transport speed, trying to use an MRL of a certain speed to cal a transport at a different speed is the most sizeable PITA, and ultimately it comes down to how many tones are on the tape...if using a 15ips tape to cal a 7.5ips transport everything is halved...1kHz tone will reproduce at 500Hz etc. So if the 15ips tape only goes up to 16kHz then the highest tone you will be able to reproduce is 8kHz which, depending on the machine, may not be adequate for fine-set azimuth and/or checking your HF response in order to diagnose the health of the heads, etc.
Yup. That was more than you wanted to know.
Look at these tapes on the linked catalog pages...same standards (i.e. 250nWb/m, IEC 15ips), but one has more frequencies:
31J229 $220
341-673-482-103 $145
There is another guy who attempted to record some stuff the weekend before and wasn't very successful. Wonder why... Oh well. I'm starting to wonder if my TSR-8 and 38 are calibrated for two different tapes. I was hitting the tape pretty hard on the TSR-8, yet when I brought it home and played it back on the 38, the meters didn't move around as much as I expected. I really need to get a MRL tape and just get it over with. Which one would I need to get for +6 tapes?