Tascam 312B Project

[sweetbeats]

Haha...no...I just have a lot of random sh1t laying around. Actually the switch in my hand there is in my personal spares for the Tascam M-__. It’s from an M-308 I parted out years ago. I have a super-janky M-312 in the shop that I think is going to suffer the same fate.

I’ll send you a PM.

 

[bachelorb]

Haha...no...I just have a lot of random sh1t laying around. Actually the switch in my hand there is in my personal spares for the Tascam M-__. It’s from an M-308 I parted out years ago. I have a super-janky M-312 in the shop that I think is going to suffer the same fate.

I’ll send you a PM.

I'll send one back.....except......

sweetbeats has exceeded their stored private messages quota and cannot accept further messages until they clear some space.

......and clean those voicemails off your phone too......

 

[sweetbeats]

Whoops...yeah it looks like it’s time to clean house a little...I cleared some messages off. Try again.

 

[miroslav]

Sweets...check your PMs...

 

[bachelorb]

alright..... The last few days have been putting the mixer back together and starting to run it through its paces, and working a bit on its desk...... along with household chores I was supposed to do long ago..... (....man these man caves are awesome!!!!).

I thought I'd mention the desk a little bit. Being a solo act, I was having a hard time trying to figure out where I could record, and check the levels and do the adjustments etc..in my new <gasp... I hate to use the word..... > "studio" layout...... then along came this $2 beauty..... on rollers!!!!.


...well a little implosion exercise and surgical work with the circular and oscillating saw and I ended up with this:



It actually will have more rack space than what I have now..... kinda a "going mobile" on steroids. Here is the finished version (I still have to install the rack...maybe tomorrow since the temp is supposed to be 48F with 40 mph winds.....)



The beauty about this is all I have to do is unplug the monitor outputs and everything else will be contained in the desk. I can wheel it over to my recording area and get levels and adjust as needed.

I'm thinking about adding a trailer hitch and starting a new "going mobile" thread

Brad

 

[bachelorb]

Working on the desk today, and I started wondering how other people set their recording levels when they are by themselves. I, perhaps narrow-mindedly, made my board mobile.... but how do y’all do it when you can’t move the mixer?

 

[sweetbeats]

I get a helper.

 

[sweetbeats]

Even somebody with no tech experience can follow the “I’m gonna thump the kick drum...you slowly turn this knob until that red light flickers, then back the knob back off a little.”

 

[bachelorb]

Even somebody with no tech experience can follow the “I’m gonna thump the kick drum...you slowly turn this knob until that red light flickers, then back the knob back off a little.”

.....shoot..... I was thinking with all you techies, there would be cameras and servos involved........ I am a little underwhelmed.....

 

[skywaveTDR]

Wow I never took one apart that far as it usually is not needed. I did own a M320 for a while when I did a Radio Program for a Church.
Kind of seems to me that unless you are capable to repair anything in the mixer that taking something apart to this level is asking for trouble.
Why did the front panel have to come off as Windex can clean most panels off without taking all that apart?

 

[sweetbeats]

Wow I never took one apart that far as it usually is not needed. I did own a M320 for a while when I did a Radio Program for a Church.
Kind of seems to me that unless you are capable to repair anything in the mixer that taking something apart to this level is asking for trouble.
Why did the front panel have to come off as Windex can clean most panels off without taking all that apart?

No...I really can’t think of a legitimate reason for any of the times I’ve completely disassembled stuff I’ve taken apart...M-308, 388, M-520, M-512...but I did it because it afforded me the ability to comprehensively deep clean the unit. And that’s something I enjoy doing. It’s hard to really clean well around all the pots and with dress panel clear of the pots you can really wash it, and even wax/polish it if you want. I did this on my Tascam prototype console because the paint was a little oxidized. I think the same with a 388 I refurbished. You can make it minty. But I’m the kind of guy that washes the pot nuts and cleans the threads on the pots when doing a refurb. Sometimes if you want to really service the pots and push switches you have to get each card free...so, as far as repairs go, no, I can’t think of a reason I would have ever *needed* to pull something all apart, but the times I have I’ve enjoyed the process, learned a lot, and ended up with a nice looking unit at the end. The big caveat is taking it apart opens the door to possible damage...messing with stuff that doesn’t take well to being disconnected and reconnected...you can create cold solder joints when you pull apart some of this 3-4 decades old stuff that is made up of phenolic resin boards, so I always enter a refurb project with the assumption I’ll have repairs to do related to the refurb process, but fortunately it’s been rare that actually ends up being the case, and when it does happen it’s actually a revelation of something I might likely have had to battle with down the road even if I hadn’t pulled it apart...the disassembly affords the opportunity to catch stuff that needs preventive repair or maintenance, and to me that adds value to the refurb. If I’m going to refurbish something and re-sell it, my goal is to pass on something to somebody they can count on...I don’t like worrying about the reliability of my gear. I certainly don’t want somebody else to feel that way about something I sold them. Brad may have a completely different set of reasons, but those are some of my thoughts.

 

[bachelorb]

Wow I never took one apart that far as it usually is not needed. I did own a M320 for a while when I did a Radio Program for a Church.
Kind of seems to me that unless you are capable to repair anything in the mixer that taking something apart to this level is asking for trouble.
Why did the front panel have to come off as Windex can clean most panels off without taking all that apart?

.....yeah..... whats that old saying....... Experience comes from bad judgment, and good judgment comes from experience...... I am becoming experienced...

I thought since I was going to own this for a while, I'd clean everything..... welll.... after turning the 312 into the equivalent of an electronic jellyfish, I realized how this might not be a good idea.... The whole experience cost me one meter switch and a whole lot of aggravation. I think when I get this urge again, I'll do it in sections ( disclaimer:.....at this point, I do not ever think I will get this urge again........)

 

[bachelorb]

Alright..... I am starting to think about getting the 312 cabling set up for recording. This is going to be a little different beast than the M-106 and I am just trying to get a feel for starting the layout. I was going back over some old posts and ran across this one when I had the M-08 as my mixer and everyone was helping me figure it out.

The mixer you have can be made to work.

For me though, this is my preferred set up with any rack mount cassette.

Get twice the mixer channels than you have tape tracks.

For a 4 track, 8. For an 8 track 16.

With this setup you can have channels 1 thru 4 set up for tracking. Channels 5 thru 8 are for monitoring what's already been recorded.
Come mixdown time, your tracking channels (1 thru 4) can now be used for effects returns, additional sources such as audio from a midi source, etc.

Personally, I'd prefer a 16 channel mixer. There are bunches of good affordable ones that will fit in a standard 19 inch rack space.
Besides, should you want to go 8 track, you're already set up.

Anyway, I'll shut up. I've already caused you enough trouble.

Is this a pretty good baseline to start with?

Thanks as always,

Brad

 

[sweetbeats]

Well, yes, for a mixer like the M-08.

The biggest differences with the M-312 is you have 4 mix busses plus a stereo buss that are independent and can be monitored via multiple means (vs just the stereo buss on the M-08 or 2+2 mix busses on the M-106 that can only be monitored either/or), and you have a monitor mixer designed for accommodating 8 dedicated tape returns and this submixer can be accessed in the monitor buss and also inline on channels 1~8. The M-08 has nothing like this, and while the M-106 has the inline monitoring on each of its 6 channels (the LINE source switch by the green AUX knob on each channel), there is no separate monitor mixer or dedicated tape returns.

So the advice to get a mixer with twice as many channels as tape tracks is good advice if it is a mixer with basic topology, like an 8x2 mixer with no inline monitoring. This can work perfectly well if that basic mixer has direct outs because, let’s say you have a 4-track recorder and an 8x2 mixer, channels 1~4 are your sources, their direct outs feed your recorder inputs, and your recorder outputs go to channels 5~8. Your stereo buss is free to be used for monitoring, and you have enough inputs to monitor and/or track as many recorder tracks as you have, and enough channels leftover to monitor any or all recorder tracks for overdubs and/or mixdown. Simple but elegant. It works.

But it starts to get large when working with an 8 or 16-track recorder. Yes...there exist very big mixing desks, but for a project or home studio space is often a factor. Plus, what if you have more sources than recorder tracks? Then you either need more mixer channels than twice your recorder tracks, or you are repatching sources. Or what if you want to submix something onto 1 or 2 recorder tracks? Like drums for instance? Well now you've got to use that stereo buss for submixing and it quickly gets complicated when the talent needs a cue mix, and you as the engineer need an independent cue mix, but your stereo buss is being used for a submix. Nothing wrong at all with a more basic setup, but it lacks flexibility, and that’s where something like the M-312 is great.

SO...the M-312 will easily handle an 8-track recorder. It was designed for it. And, IMO, 12 mix channels is a nice number for an 8-track setup in most circumstances. The M-312 has a really nice feature set for a 12x4x2 mixer. And I think it’s pretty decent sounding. And as you have found they are affordable and can be worked on. Separate channel cards, individually nutted metal pots, and some like yours came with those nice vertical ALPS faders...all based around the 5532 opamp which, though it is vintage, still carries a pretty good amount of respect. I think you’ll be happy with the sound and will enjoy using it.

HTH

 

[bachelorb]

SO...the M-312 will easily handle an 8-track recorder. It was designed for it. And, IMO, 12 mix channels is a nice number for an 8-track setup in most circumstances. The M-312 has a really nice feature set for a 12x4x2 mixer. And I think it’s pretty decent sounding. And as you have found they are affordable and can be worked on. Separate channel cards, individually nutted metal pots, and some like yours came with those nice vertical ALPS faders...all based around the 5532 opamp which, though it is vintage, still carries a pretty good amount of respect. I think you’ll be happy with the sound and will enjoy using it.

HTH

Thanks, I was getting confused a little. Mainly because I wanted to see if I understood the concept a little before I referenced the manual.... I obviously did not..... but I'm getting closer.....

 

[bachelorb]

XLR Patchbay for line level signals

I have been looking at how to patch in the inputs now into the 312. Once again (especially now) I want to keep everything in front of me. The 312 has XLR mic inputs (and line inputs, but I'd rather not use em). The manual says I can use the 30dB pad switch and trim to make the mic input act as a line level input. This would help me space wise because I don't have room in the roller desk for another line level 1/4 inch phono patchbay and an xlr patchbay. I guess I have two questions on this:

1. Is this done a lot? and if not, why not??

....and.....

2. lets say for the sake of argument that the operator is dumber than a sack of hammers..... and lets say he hooks up a line level source to the XLR patchbay and he's forgot to turn off the phantom power....... will the operator feel the need to string together enough compound words to make a drill sergeant smile???? or will he live in blissful ignorance unaware of his neverending incompetence?????

(.....and yes I realize that was four questions..... )

 

[sweetbeats]

1. I avoid it. The feature is certainly there to use if needed, but I see it more as a “just in case” tool. A pad on a mic input could also potentially come in handy if you have a mic on a very loud source, and the mic has a relatively high output, so the pad isn’t just there so you can use the mic inputs as balanced line inputs. I recall, and I can’t remember specifics, a time I had a condenser mic on something loud...the P48 was on and I couldn’t turn the mic trim down enough to keep it from clipping...turned off the P48 and I didn’t have enough gain. Switched in the pad...perfect. But yes you can also use the pad to allow line level signals into the mic amp. But...I avoid it...because you are then sending your line level signal through a set of resistors (the pad...that’s all it does...routes the signal through a set of resistors), and then re-amping a now small signal through and amplifier to make it big again...lots of unnecessary circuitry to send your signal through. Avoid chasing after making everything balanced unless you are having a problem with noise interference...! And even then, try and abate the noise problem without balancing the signal. Balanced audio doesn’t sound better. In fact it *always* involves sending the signal through more circuitry, at least in the case of transformerless balance amps. Now if you are looking for color, then maybe transformer balancing is something to try, but otherwise understand balanced audio came from the telephone industry as a means to deal with RFI with those long cable runs (100s...1000s of miles). In most of our studios, project and home-based, we don’t usually have more than a couple dozen feet if that. Balanced audio was brought to the audio production world as a means of abating noise intereference, not because it sounds bitchin’. The bitchin’ part probably grew from the character a transformer can impart, so if you are looking for color then, again, that’s something to try. But not all transformers are created equal, and many are mediocre to garbage. Good audio transformers aren’t cheap.

2. If the operator applies phantom power to a line level input, he or she will likely be coming here asking for help with the source device that now has no output. I’d be keeping them separate.

What stuff you got with balance line outs that you want to keep balanced? I know I just ran off at the thumbs in #1 there, but I’m curious...I was only speaking of my ideology...which I guess I’m a hypocrite because unbeknownst to the homerecording.com world as of late I am exerting a decent amount of energy trying to work through finishing what Teac started and adding 12 balanced line outs and 12 balanced line inputs to the Tascam M-__...and I’ll never use them if I’m tracking with the 58...if I’m tracking with the MM-1000, well, I might use them there, except that there’s probably a significantly audible difference in fidelity when bypassing the transformers. ANYway...

 

[bachelorb]

What stuff you got with balance line outs that you want to keep balanced?

Its not so much balanced as it is having a line level input vs a mic level input. I went through a bunch of tests today to figure out what I need of each. My guitars (save one) worked well with a line level input. The Barcus Berry Maple Bar guitar pickup didn't seem to leave to much headroom for recording (when I say headroom, the trim was most of the way up and so was the fader). My dynamic mic had the same problem. I seemed to have more room when I hooked into the xlr mic connector.

On the M-106, they were all phono plugs with a switch for mic-atten-line. The 312 doesn't seem to work that way. If I am hooking up a mic, it seems to need to go to the XLR which can be switched to line level, but the phono "line in" plug doesn't seem to be able to be switched to mic level.

so if I'm understanding this right, I need to dedicate a certain number of channels as line level inputs, and others as mic level inputs with the knowledge that the mic level inputs can become line level inputs if needed with the use of the 30dB pad switch...... but I'm not sure I'm understanding this right.......

 

[sweetbeats]

The XLR inputs are mic inputs. Period. They can, if necessary, accept line level signals with the pad switched in, but the XLR inputs are mic inputs with a mic head amp and everything. The 1/4" TS jacks are your line inputs. This is more the standard arrangement; separate inputs for separate types of inputs, vs. the M-106 arrangement which is relatively unorthodox.

In a typical studio where the scene is changing all the time, you would have a snake from the control room to the tracking room with a fan or jack box permanently connected to the mixer. After each session instruments and mics would be disconnected and the mixer "zeroed". Next session comes in and plugs up to the snake, new ink goes on the scribble strip, levels are set and away you go. Your situation is more of a permanent install, so just like you're doing you want to be mindful of how you have stuff connected to retain maximum functionality with minimal need to re-patch.

And, yes, if you are wanting to connect your sources and leave them connected, then you would have certain channels for mic sources and certain channels for line level sources. And let me suggest you use channels 9-12 for line level inputs.

Are you sticking with a 4-track tape machine for now?

Do you have more line level sources than 4?

 

[bachelorb]

Are you sticking with a 4-track tape machine for now?

Do you have more line level sources than 4?

I am sticking with the 4-track and right now I don't have more than four line level sources. Realistically, the most I could use at one time would be three line level sources.....Thats not to say that someday I might find a friend and we might get together and record something

I am looking for kind of a general ratio of mic input to line level inputs. Right now, I'm thinking of dedicating two channels to mics needing phantom power (since phantom power covers two channels at a time). maybe two (or more?) dedicated for dynamic mics. I guess I could have all 12 channels be line inputs and just switch off to the mic input with the line switch if I'm using that channel with a microphone right?

I'm just trying to feel my way through this....sometimes not even using the manual to impress everyone with my vast knowledge..... <insert the "I'm full of sh?t" smiley thingy here>

once I get it set in my mind, I want to draw up a diagram and run it by y'all....

Brad