TASCAM M-320B VU Meter Routing Modification

[DieterS]

Hello TASCAM Users! I just joined the forum as I recently acquired a TASCAM 38 reel to reel and a M320B console. I like that there are 8 VU meters (in addition to the L R Main out VUs) on this unit but the routing seems odd or non-intuitive to me and as such, I normally only see the master L R meters in action. I would like to see 8 channels of source (mic or line in) assigned to the VU's. I'm wondering if anyone is like minded on this and if anyone has performed circuit mods to this end? I would be interested in learning about your experience and how it turned out. Thanks! (Same thread posted in TASCAM User Forum)

 

[miroslav]

Not familiar with the M320B...but those 8 VU meters are most likely meant for reading the return signal from the tape deck.

To monitor the input, just allow the signal to pass through the tape deck with the deck set to either Input or Simul-Sync (monitoring off the record head) and that will feed the VU meters on the mixer...and there's your input signal....assuming you have the tape deck and mixer hooked up correctly.

Also...doesn't the tape deck have meters too for input signal...?

 

[RFR]

From looking on line at the console, it would appear that the meters only are for the busses. It's a 4 buss board with switching for the meters. Although there are 8 meters, only 4 at a time are active.

So it would seem.

Sweetbeats? You out there?

 

[DieterS]

From looking on line at the console, it would appear that the meters only are for the busses. It's a 4 buss board with switching for the meters. Although there are 8 meters, only 4 at a time are active.

Right, and this is the crux of my issue. What's the point of having 8 meters if only 4 are active. I would like to reassign the VU's to the inputs with circuit modification and hoping someone has successfully beat me to it. I'm not an audio engineer but I thought gain stage control was one of the key attributes of successful analog recording. I would like more than an OL led to monitor input levels and I like to see what's going into the board as well as what's coming out. Maybe I'm thinking about this all wrong but that's the basis of my question.

 

[miroslav]

Again...your TASCAM 38 has meters for monitoring input signals...just use them.

 

[RFR]

I'm sure there is a way to get what you want, and it would make it more useful.

I have an M520. This has 8 meters for the 8 busses. But on the meterbridge, it has in and out jacks and I can switch the meters between internal and external use. Comes in handy.

Im sure something like that could be rigged for your desk, although I don't know how, or who does.

All that being said, as Miro says, just use the meters on the TSR 8. They are more accurate. As long as you're using the buss and no more than 4 tape inputs at a time you have use of the consoles metering also.

For myself I never use the internal meters for tracking, because I never use the buss. I go direct out from the 1st 16 channels of the board into the MSR16. The direct outs bypass the board's meters.

The levels to tape, are in my opinion, more important than the board levels.

I've found pushing these old boards a bit on mixdown gives a nice warm saturation to mixes.

Anyway enough babble. Good luck with your quest. Despite it's limitations, its a nice good sounding board.

 

[miroslav]

First thing you need are the schematics. You might be able to figure it out without them, but trying to read traces on a PCB is a PITA.
Then you need to find out what kind of signal is needed for the meters...basically, what's the current circuit on the group buss side like...are there any components before the meter that buffer the signal going to them or is it a straight split off the group out signal...?
Then you need to figure out how to create that same circuit path with whatever components are included...for each of your channels.

Not impossible...but certainly easier to just use the 38's input meters.

There are mixers that only give you two main stereo meters...and it's really not an issue because usually you are feeding the inputs with signal from some other gear which probably has metering. So...if you get the signal right, and match your reference levels...there's not any need to see that same signal on another set of meters.
For mixing...the signals have already been recorded...the meters on the deck have confirmed their levels...so all you really need to watch are the two stereo out meters.

That said...I like meters too...they're like s security blanket seeing them moving, and getting that additional confirmation about the signals...though personally, I prefer segmented peak meters for individual signals. VU meters are good for main bus metering. That's one thing I liked about my TASCAM 3500...it had segmented peak meters on the channels and two VU meters for the stereo output.
The Trident I just got only has 24 + 2 VU meters...and I think the 24 meters also only function on the group buss, which is for the tape returns...but I still haven't hooked it all up yet, so I'm not 100% sure. Anyway, I have my tape deck meters for input monitoring, so no big deal, it's just that I could see the segmented peak meters from across the room...the VU meters, forget about it.

 

[DieterS]

Hey RFR and miroslav, thanks for your feedback. I do have a full set of schematics but wanted to hear others experiences before I set out on my own. After looking again, it does now make complete sense to just use the 38 meters as the D-Out's are in front of the Ch-on button which is where I was originally thinking the meters ought to go. So thanks for saving me from an extended exercise in futility and for the extra pointers!

 

[RFR]

No problem. We all learn something. (Hopefully)

In practice you'll find you won't need them or miss them.

On my 520, which has a lot of similarities, the only meters I really use are 7 and 8 which correspond to buss 7&8.
Since the 520 doesn't have a dedicated one fader "stereo out" to feed a mixdown deck, I'll use a buss. Sometimes I'll mixdown to multiple machines, and then 4&5, 5&6, and 7&8 are active with board metering.

In practice since I never use the busses other than for mixdown, the only meters moving are 7&8. I do use those alot cause I want to make sure I'm not clipping my output buss..

While I could use the buss to send my signal to tape and have metering available, I choose not to. I'd rather have the cleaner path of an individual channel going to direct out.


For tracking I'll get a sound I like, making sure that the clip light doesn't come on. The main guage is the meters on the deck.

In the rare case I want to setup say a drum buss to two tracks of tape, then I'll send them through a buss, and have metering. But with 16 track that's mostly not needed.

While I have 4 more meters switchable from aux out to monitor out, don't use those either. For monitor out, I'd have to crank my control room speakers to deafening levels just to see any range of motion on the VUs. For aux out, once again I'm relying on the input meters of the outboard gear. Clipping a digital reverb doesn't sound nice.

So, in closing this long winded story, my metering on the console pretty much consists of 7&8 being used as master out, but the "real" metering I am going off of, is the input of the recording device being fed by the board.