+4 to -10


New member
hey there,

i've got a setup of +4 mic pre to a +4 compressor to a +4 eq out to a -10 tape deck. could anyone suggest where the best place to cut my output is. i've been pumping +4 all the way to the eq and then cutting back at my eq output but i'm wondering if i really should be cutting my output right from the pre-amp.


I'd put the EQ before the compressor, and turn down the output at the compressor thereby solving two problems at once.
I would buy a +4 mixdown deck!!! :) Your sound will greatly improve by this move. You are missing out on about 14db of dynamic range. Gonna need to squeeze that mix quite a bit on the compressor just to keep things from getting out of hand. Output conversions are not really a great way to keep a good sound going throughout your signal chain. Is it a cassette deck you are mixing to? If so, I am sure that you can find a nice Tascam with +4 inputs for around $250 or less.

Also, you may already have a -10 output on one of those devices. I know that often, EQ's will have a +4 and a -10 output so that it can interact with a variety amplifiers and what not. Check your owners manual.

Ed Rei
Echo Star Studio www.echostarstudio.com
hey sonusman,

thanks for the input. yeah, i do have a 1/4" out which i'm sending to my deck. can't upgrade the deck as it is a tascam msr 16 1/2" which i invested a lot in. do you think there is anyway to hot rod this deck to make it +4?


While I am not the biggest analog dude around (actually, never considered it an option when I built Echo Star) I have a friend with the 1" Tascam 16 track machine. When I first met him, he was running -10 on the deck. He found the upgrade kit for his machine and is currently running +4 on it. Boy, what a difference that upgrade made to his recorder!!! I would visit Tascams website and look around to see if a -10 to +4 upgrade is available anywhere. If there is nothing on the website specifically about this, try sending their tech support an email asking if it can be done for your machine. If it can't, you may consider selling the machine and getting ADAT's. One should never have to live with -10 record levels for any professional application at all!!! :)

Good luck.

I have a bit of confusion with regards to the -10dB, +4 scenario. From what I understand, these are both just levels, but 2 different standards/calibration. +4 is certainly a hotter signal, but thats all. I could see an advantage to a +4 setup since this is usually always a balanced enviroment, and would help reduce RF intereference. But with short cable lengths and good quality cable, I can't see how this would relate to fidelity in a -10 system.

If however, one were patching signals of -10 to +4 I could see a problem in trying to make up the gain, which would result in degradation.

It really doesn't matter. As long as levels are hot without noise.......record. It's just a wiring scheme really. I have a studio with balanced and unbalanced, -10 and +4 stuff. The only problem is that some good gear is only +4, but the better gear is +4 or -10. Get good levels, no noise and record!!!
Have it your way guys, record -10..... :) If you don't think there is a difference, well, good luck....... :)

finally got a response from tascam. spoke with a tech out there and he claims that there are two units i need to get an la-80 and an la-81. BUT... he claims that converting to +4 will only add more noise to my setup. he said the only reason to go +4 is if i'm stringing cable over 20 feet. any comments?
What he may mean, is that when you clamp on a unit that is going to do this conversion. There will be hardware involved, namely tranformers, which will add noise. Also if there is some physical interface, your up against some resistance, which could cause some miniscule problem. Unbalanced has already been proven to be quieter. It's a great topic. Wish someone would come up with a good, realistic and especially - technical clarification. -10 is a japanese standard.. consumer, pro-sumer. dB remains the same. Headroom is status-quo, in context. You pro's out there, please, shed some light.

Just from the fact that the +4 format is a hotter signal than the -10 system means that upon digitization, each amplitude increment is represented by a larger voltage increment.
Since any D/A converter is limited by its voltage sensitivity, providing more voltage allows more accuracy in the conversion.
i.e. more headroom.
Does this make sense or am I all wet?
Electronic noise floor to max record/playback level. With +4 levels, you are getting an extra 14db of dynamic range before distortion. Forget all of those obscure things any of you all may be reading. There is a reason that Pro-Recording standard has been +4 for eons. Did any of you know that 3M made a machine that recorded/played back at +13 once? Required special tape. Regular 2" tape would melt on the heads!!! LOL Can't remember who it was that made a machine that was standard at +6. Anyway, more headroom, more dynamic range, better signal to noise ratio. Blah Blah Blah.

Oh, by the way, the Japers also embraced the minidisc system. And invented Kareoke. And Teac (who is the parent company of Tascam. They bought them out years ago so they could have Pro quality gear available) has a vested interest in keeping the waters muddied. They don't want to go the route of retooling the whole thing to accomdate a different scheme.

If you have a digital system with -10 +4 options on the A/D,D/A converters, try them both. Try to tell me that there isn't a significant difference.

Also, there were -10 balanced components. Plenty of +4 unbalanced also.

About introducing noise to your recorder. Emeric is sort of right. If the conversion kit is a step up transformer kit, then the transformers will add distrotion. That could constitute noise I suppose. But as far as adding noise as like in rushing noise (sounds like a waterfall) I don't think that is going to happen. Yes, any noise that is present will be that much louder, but, by contrast, so will the audio signal, so you will retain, if not improve your sound to noise ratio.

Bottom line, if the conversion kit is replacing the OP amps on the recorder, go for it. You WILL be happy that you did.

I will not respond any more here. (Unless something really crazy is said, like Slash is a better guitar player than EVH :) )

thanks for all of the input on this topic. i did not get much information out of the tech at tascam but come to think of it he DID say that the two units i needed (for input and output) were rack mountable. i'm going to assume that that means it is a step-up - step-down process. (though i was really looking for a it that would actually replace the inputs on the machine) i could see now what he meant by adding noise (he was very vague and sounded like he just had some bad clams for lunch)but i can also see about how the added headroom will improve sound quality. the ayes seem to have it with this one. now i just have to find out how much this is going to be. thanks again

Thanks Ed,

I do have +4 and -10 options on my gear, but I am limited by the number of outputs on my mixer (+4 outputs) Assuming there is a difference.. :) do some instruments benefit more than others? I can only use 4 balanced outs.. should I send the kick snare and left and right oveheads out of those and leave the toms in -10 land? Will mixing -10 and +4 pose any problems? I can send my monitor mix back in +4. I could track everthing else in +4 - guitars, bass, vocals etc.. I guess I better just try it and shut up now... :)


[This message has been edited by Emeric (edited 10-17-1999).]