Really basic recording console question

Cliff Kane · From: the late great golden state

Hey folks, I've got a really basic question regarding what is okay to plug directly into a console. I don't know any about this, but I've aquired an old Tascam mixing board and a Fostex 1/4" tape machine, and would like to play with it (I'm not even sure if I'm going to keep it--got it in a trade), but I don't want to damge anything. I know people use direct boxes (why?)--which I don't have--and mics--which I don't have yet, but I'm wondering what the rules are on pluging straight into the console from the guitar, the external speaker jack on the amp, or the "monitor out" jack on my old Gibson Falcon amp. What about the output of a cassette recorder? This Tascam console has both 1/4" and XLR inputs.
I know this is a very basic and general question, but I'd like an idea of what is alright to do and what can damage something.

Thanks for your help.

Ken Lang · From: Simi Valley, Ca

Cliff: Far as my experience, in the simplest form, you can plug anything into anything as long as they are musical stuff and not of the 120 volt kind. The worst you might experience is distortion from too hot a signal, ie a speaker out from an amp, rather then a line out. Start with the volumes low and work up. I'm sure others can explain better, but it's a start to your question.

John Lacey · From: Black Diamond, Alberta, Canada

Cliff, I would try plugging in direct from your volume pedal just to see what kind of a tone and volume level that you would get. If the volume's too low, you might need a direct box to pump it up. The external out from the amp might work fine to go directly into the board. Watch your meters or LED's for peaking levels and run them below say, 0 db. Another route to go would be to run into a multi-effect unit then into the board. This will give you an added signal boost.

Cliff Kane · From: the late great golden state

Thanks Ken and John--going from what you say, it doesn't sound like I can damage anything, even with an external speaker out from an amp. This is what I was wondereing about; thanks for your help!

Cliff

Donny Hinson · From: Glen Burnie, Md. U.S.A.

I'm no expert, but I would NEVER run the speaker output of an amp to anything but a speaker (or a good set of headphones)! The voltages present at the speaker are MANY times higher than anything that's designed to go into a regular "input" jack. Use the "preamp out" jack on the amp. If your amp doesn't have one, then get a cheap mixer, or use a direct box.

You can "screw up" with a piece of tube equipment, and get away with it. But, with solid state equipment, all it takes is short, or an overload for a fraction of a second, and it's GONE!

Been there, done that!

Cliff Kane · From: the late great golden state

Hey Donny--Yikes! That's the kind of stuff that I'm worried about--but I'm kind of ignorant about what is an exceptable "level" for a console's input. Any idea on what a safe reading from a volt meter across the tip and sleeve of a 1/4" guitar cord plug might be? I guess I'm gonna have to get me a mic, but it would be cool to know why and why not I can do things with this gear. Also, will a direct box make all signals coming out of it okay for a console's input, e.g., an "external speaker" jack going through a direct box will come out of the box at a safe level? I know these things have something to do with impedence, but I'm not really sure what that means.

Thanks,
Cliff

[This message was edited by Cliff Kane on 26 November 2000 at 10:11 PM.]

Rex Churcher · From: Honolulu, HI, US

The signal level from your steel is about 150mv, which is somewhere between "mike" level and "line' level, which is approx 1volt.A good match would be to feed from the line out on your amp into one of the line inputs on the Tascam. Adjust the sensitivity control,(top knob on the board) to get about -6db on the VU with the level control about 50%. If you have the model with the XLR mic jacks you have the top of the line. But . let me warn also, NEVER ever try any experimenting with the speaker output connections. The danger of shorting the output transistors is too great and VERY expensive to repair.

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basilh · From: United Kingdom

Cliff, MOST boards will take +4db on their LINE input (0db being .775v @ 600ohms)
it is also usual to have about 12db headroom on a desk input op-amp,so you see the output from a speaker even at low level could easily excede this figure.
Remember what Donny said and NEVER run a speaker output from an amp into anything other that a speaker (or speaial D.I.Box designed for speaker input..like the one peavey make)

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Basil Henriques
Emmons D-10 1970
and
Emmons D-10 1970 "Anniversary"
1949 "Leilani"
1949 Dickerson
RICKENBACKER "Olde Uglie" Twin 8
"Fender 1000"

gary darr · From: Somewhere out in Texas

Cliff,as for the monitor out on your gibson amp being suitable,I think a quick way to check is run a cable from it to a extention speaker cabinet.if it does not have enough signal to power the speaker, chances are the signal is low line level which could be used as an outgoing signal for that board.I would however still exercise caution when bringing up levels just as a good rule of thumb.I have recorded some pretty descent tracks on my tascam four track coming straight of the volume pedal to a peavey board then into the four track.dont be afraid to experiment with different methods of recording,thats half the fun of it. Allso one note is just because the signal is compatable does'nt mean that it will be a good clean signal,let your ears be the judge. My $00.02 worth D:

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sho-bud,session 500,american standard strat,shecter tele,peavy classic 50

Cliff Kane · From: the late great golden state

Hey folks, thanks for more good advice--well, I sure won't be pluging any speaker outs into anything but a speaker!
Gary, that's a good idea to check the level coming out of the "monitor out" jack on the Gibson...I remember reading somewhere that this is a sort of line out to drive another amp (I heard that Ry Cooder does this with an old Gibson amp), but who knows? It's a great sounding amp, though. I'm gonna hook this stuff up and give it a go--if all seems to be working I guess I'll have to get a mic to take advantage of the great live echo chamber here (bathroom) and all the variety of percussion instruments we've got (pots and pans, baby toys...) Lo-Fi here I come!

Steve Stallings · From: Houston/Cypress, Texas

Oh my....you seem to be on that slippery slope which leads to serious G.A.S. (Gear Aquisition Syndrome). Lot's of good tracks have been recorded on the gear you now have.
Get yourself a sm 57, put it in front of the amp, and have a ball. Hmmm....what will you use as a mixdown deck? Get out the checkbook

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Steve Stallings
Bremond, Texas
Carter D10/Evans

Rick Barber · From: Morgan Hill, Calif. USA

Here are some general tips that may not always apply but here is my experience using modern equipment. Never plug a speaker output into anything but a speaker otherwise you will destroy your equipment and even your dwelling as someone already said. :

mixer inputs use lower level SIGNAL inputs , around 1 Volt for Line level and much lower for microphones or pickup outputs. Line level varies depending on whether its consumer equipment or pro equipment. Your manuals will tell you.

a line level signal will usually come out of your preamp or processor or from a tape deck monitor or your CD player deck or tape player deck that has line level outs etc...

the mic inputs will be for signals much lower maybe 30 to 50 dB lower so the mic inputs of a modern mixer have "low noise" preamps built in to build it up to linelevel internally. Modern mixers not only have low noise preamps on the mic inputs but also they are designed to handle a bit of overdrive incase your live source level climbs. People doing recording often use compressors or dynamics processors which automatically boosts the level when inputs are low and limits the level when it gets to high . That way you dont "DISTORT" (*#(*&@*)(*&(&@#R( . Example I use DBX equipment.

some mixers have balanced inputs accepting a mic cable (XLR connectors having three contacts). Balanced low impedance is good for running long lengths without picking up much noise or rolling off the highs. Example 100 foot microphone cable snakes are still sounding great because they use balanced cable which you hookup up to a balanced source on one end and a balanced load on the other end.

direct boxes are typically arranged so you can plug in a low level UNbalanced signal source from your pickup or level source as an input to the box then the output is taken as a balanced (xlr connectored mic cable ) which you can run over to a mic input. It is important not to offer more signal to the direct box than it will handle , otherwise it will distort on its own. Secondly you need to be able to adjust the gain of the mixer preamps so they dont distort.

So from a guitar (or steel) you can use a Y connector at the input , you plug in the Y into the directbox in then you hook unbalanced (guitar cables) one goes to your guitar , the other goes over to your guitar amp input. The output of the direct box then goes over to mixer.

Know the levels of all your ins and outs. Not sure then ask the vendor.

Also note that so called Powered Mixers have power amps and low impedance at the output so you hook those into speaker systems.
So be careful what you plug such a device into as it has a high power output to drive whatever impedance it says you can drive. Dont know what your mixer is .

My Mackie mixer has Line level outputs so I hook the outputs of my mixer to the inputs of a stereo power amp. That is because they are Line level outputs which have to be boosted up using a power amp then the power amp outs are hooked up to speakers.

Read the manuals for your gear to make sure you hook things up correctly. Many vendors have 1-800 numbers and application engineers.

Hope that gives you a bit of an overview.

Before you buy anything go to Barnes and Nobel Bookstore maybe and buy a small book on recording setups or live sound setups. The internet in general has many sites with all this info. The manufacturers of mixers typically have lots of this info too.

My advice is do a little research before you plug and play. You'll sound better and you will be operating your gear in a safe manner.

Rick Barber

Rick Barber · From: Morgan Hill, Calif. USA

When I said hook up from direct box output to Mic Input I mean the Mic Input connection at your Mixer input panel.

Rick Barber

Vernon Hester · From: Cayce,SC USA, R.I.P.

Most audio boards operate with a mike input level of about -60db. If you read the specs of most pro-mikes you are looking at and avg -55db at 150 ohms. Broadcast line levels are +8db ref to 0db =1 millwatt at 600 ohms which is hot compare to high imp cassette players,etc, Guitars run from 40 millvolts to
262 millvolts my C6th neck strumming all 10 strings with a Bill Lawrence 705 pickup avg about 242 millvolts.the E neck with a 710 is about 172 millvolts.you can make a simple pad and plug into the mike channel e-mail me and I will send you the info.
Vern

Al Marcus · From: Cedar Springs,MI USA (deceased)

Hi Rex, how you doing in Hawaii? The last time I saw you was in 1977 in St.Louis. Good to see you on the Forum.....al

Cliff Kane · From: the late great golden state

Right-on...thanks, guys, for more helpful info! Rick, your "general tips" are really a helpful overview. Now I've got more of a grounding, a more balanced view on it. I'll be doing more reading and looking for a used sm57 and D.I. box. I got this gear for next to nothing: it's old, and I guess it's considered to be obsolete as it's analog, but it seems to be in decent shape. Besides I like the idea of cutting up pieces of tape, tape compression, all of that low-tech stuff. I've been told that there are a few good books about the old Beatle sessions: one by George Martin called "All You Need Are Ears", and one that details how they made their recordings. Anyone read these books? Seeing how my favorote records and studio sounds were made in the old days, this should be a fun endevor. Thanks again for the great responses.

Cliff

[This message was edited by Cliff Kane on 29 November 2000 at 08:52 PM.]

Terry Downs · From: Wylie, TX US

Cliff,
If you did take a risk and connect the speaker output to a console AND you have a level low enough to record, you wouldn't like the sound of it anyway. A speaker (not a horn) cannot reproduce high frequencies well. The speaker output signal will contain much more highs that your speaker can produce.

Back in the late 70s, Peavey introduced an EDI (Electronic Direct Interface) box that connected into the speaker output of an amplifer and provided a balanced line XLR connector output. It consisted of an attenuator, a 2 pole low pass filter, and a transformer to provide the balanced output. It was handy since many older amps had no recording output. One of the drawbacks with the EDI was that the low pass filter was arbitrarily set at a nominal breakpoint. It could not match up with a variety of speakers. It was close enough for most. It was a good innovation, but direct connections to amplifiers have always been less than desireable. The speaker can never be simulated exactly. That is why the use of a microphone on the speaker is still the perferred way in professional settings. I can see the advantages of a direct connection for home recording to achieve isolation however.

Regarding the posts about the speaker output line damage, a big mistake was made when speaker cabinets began using 1/4" phone jacks. A phone jack will short the tip to sleeve when it is plugged in. If you connect a speaker cord to the output of the amp and plug the other end into the speaker cabinet last, you will short the output momentarily as you insert the plug. If there is no signal (just quiescent noise) coming out of the amplifer, you won't do any damage. I have seen people plug in speaker cords to speaker cabinets (like stage monitors) many times with high signal levels present. I have even seen arcing on the plug as it was inserted. It is rare that this momentary short will damage an amp since the cord itself will have an ohm or so of impedance. But, I recommend playing it safe with the speaker outputs.

A side commentary, I think 1/4" phone plugs suck for all applications and should be outlawed. They were cool for telephone switchboards in the 1940s, but why the music industry has not grown out of the phone jack is beyond me. Good speaker connectors have emerged such as the Speakon, and are very pouplar. Phone plugs don't make good connection, they can easily be jerked out, and they short as you plug them in. They also set you up for a condition of giving you a amplifier input that you can touch and send a terrible hum into your amp. We evolved with XLRs for microphones. The XLR fixes all those problems problems above. Why in Y2K are we still using them. I will post a topic on this and see what we get.

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Terry Downs
http://nightshift.net
terry@nightshift.net

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