DR40 Help

[benrichards00]

Hey all,

I'm fairly new to sound recording, so here goes.

Gear being used:

• TASCAM DR-40
  
  
• Alvoxcon Dual Wireless Lapel Mic(https://www.amazon.com/gp/product/B07TRN5JT1/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1)
  

With maximum input levels on both devices, the sound still comes out to about -40 dbs. That's obviously incredibly too quiet, and when I throw the file into Audacity and amplify it, the background noise is too garbled to reduce.

Any advice on how to proceed is appreciated.

 

[BazzBass]

those are knockoff no name el cheapos. Buy quality mics

 

[Geoffrey Kolbe]

I had the same problem with another make of 'cheapo' wireless lapel mic. My solution was to build a mic pre-amp to boost the signal into the transmitter, and then it worked fine.

You may well find that a better quality mic may give you more signal, but I would be surprised if it was that much more than the cheapo mic - which is why I built the pre-amp rather than admit I should have bought a Sennheiser EW 112P unit for ten times the price...

 

[tzdvl]

I looked at your link for the Alvoxcon mic, and I know what the problem is:
It looks to me like the wireless receiver has a single-ended output (a standard 1/4 inch mono plug, or TS, tip-sleeve).

The DR-40 is NOT designed for use with ANY single-ended mic or input source. It just won't work that way.

You MUST use a mic or receiver with a balanced XLR connector.

See this thread, and the links:
https://www.tascamforums.com/threads/tascam-dr-40x-clip-on-mic-suggestions.7748/#post-37021

 

[Geoffrey Kolbe]

That is an interesting observation, tzdvl, but I wonder if it is correct? In the manual, page 46, there is a picture of signal inputs via a 1/4 inch jack. The DR-40 is designed to take inputs via a 1/4 inch jack - which is not balanced. Can you comment?

 

[tzdvl]

The DR-40 is set up to use either XLR connectors or 1/4 inch plugs. But the input MUST be a balanced signal (+/- and ground, or “hot”, “cold” and ground).

If you look closely, the 1/4 inch plug shown in the manual has three sections: tip, ring and sleeve, like the plug on a pair of stereo headphones. That allows a balanced input using a 1/4 inch plug.

The output of the receiver of the Alvoxcon wireless mic is a MONO 1/4 inch plug (tip and sleeve), like a regular guitar cable. The output is single-ended (+ and ground), NOT balanced.

If you plug a regular mono 1/4 inch plug into the input of the DR-40 it will short the “ring” contact of the input to ground. You will be able to record sound, but the level will be 6dB lower than normal (you will "waste" 1/2 of the input voltage, and the level will be very low).

If you try to use a mono-to-stereo plug adaptor (to convert a mono tip-sleeve plug to a stereo tip-ring-sleeve plug), the input signal will be connected to both the hot and cold contacts in the DR-40, and the hot and cold signals will cancel each other out. If you get any recording at all, it will be noise.

The DR-40 is designed to work with a balanced hot-cold-ground input signal. Compatible microphones or mixers will usually have professional type XLR connectors, or if they have 1/4 inch plugs they will be tip-ring-sleeve “stereo” plugs.

Some other brands of digital recorders DO allow the use of mono, single-ended plugs, but they have enough gain to compensate for the much lower input level. The DR-40 was not designed that way, and does not have enough gain to compensate.

 

[Geoffrey Kolbe]

Thanks for that information tzdvl. You learn something new every day!

 

[BazzBass]

If you plug a regular mono 1/4 inch plug into the input of the DR-40 it will short the “ring” contact of the input to ground. You will be able to record sound, but the level will be 6dB lower than normal (you will "waste" 1/2 of the input voltage, and the level will be very low).

I hate to be a party pooper, but I go into my DR40's external inputs with unbalanced 1/4" plugs. No problemo at all. No loss of volume or quality. Don't know why tzdvl thinks otherwise, UNLESS this relates to microphones only,as I'm taking the two outputs from my mixer into the DR40. I can totally understand why a mic needs TRS or xlr.

 

[Geoffrey Kolbe]

I guess if there is plenty of input signal, then the fact that you are loosing 6db of it due to a balance/imbalance mismatch does not matter.

The OP was talking about a wireless lapel mic, where the receiver is plugged directly into the DR-40 using a 1/4 inch jack. There should be enough signal. My experience with a similar piece of kit led to the conclusion that the receiver input to the DR-40 was fine - plenty of signal - but the signal from the lapel mic into the transmitter was low. I solved the problem by building a small pre-amp to boost the microphone signal. The result was good audio signal into the DR-40 with no overload and good signal to noise.

 

[BazzBass]

I didn't think I was losing 6db. But you are most likely right and maybe my employment of gain staging principles helps me in this case. Not arguing, discussing

 

[tzdvl]

If you search through the older threads on the forums (here and elsewhere) you will find that a number of folks have been frustrated when trying to connect various single-ended sources to the DR-40.

It IS frustrating, but the engineers apparently designed the thing to be used with "professional" gear, and to work with balanced inputs only.

When I bought my DR-40 I was hoping to use it with my conrad-johnson stereo preamp to "rip" digital copies of my vinyl records. The C-J preamp has typical single-ended RCA outputs, and the recordings I made were unacceptably low in level.

Read through this thread:
https://www.tascamforums.com/threads/dr-40-recording-volume.6051/

If you connect a single-ended 1/4 inch plug to the input of the DR-40 it shorts the ring terminal to ground, bypassing the entire "cold" side of the differential input amplifier. You lose half of the gain, and recordings made that way will be reduced by -6dB.

If you connect a source that has plenty of gain, like a mixer console, you will be able to make a decent recording. But connecting a "consumer level" output (like a home stereo preamp, or, apparently, the receiver of the Alvoxcon wireless mic) won't work well.

I addition, you will lose the advantage of the noise reduction of the differential inputs.

If you look through the Reference Manual and the Owner's Manual for the DR-40 they indicate only that the input should be balanced TRS hot-cold-ground. There is no mention of any provision for connecting single-ended signals.

As I mentioned, some portable digital recorders ARE designed to work with single-ended inputs, but they have enough gain to work with consumer line level signals.
I think the designers of the DR-40 expected it to be used with pro-level signals.

 

[BazzBass]

thanks tzdvl that clears it up.

it's a great tool. I play my bands songs through a mixer,adding my bass to it and play along ,into the DR40, trying out various ideas then listening back. Helps me to write basslines. All three of my bands play only original music, arrrrgh lots of writing basslines lol

 

[DaveR514]

Thank you so much for the helpful input -- you guys rock!

Art Anderson -- I had not thought to make sure that the firmware is up to date. I guess I wasn't as clear as I should have been, in that the REC MODE is set to DUAL. Currently have the EXT IN set to EXT IN 1/2, and so will try EXT INDEP. as you suggest. Thank you for the super clear instructions!

tzdvl -- I was indeed been confusing a STEREO headphone TRS output with a balanced MONO TRS output. We did pop into our friendly local electronics bit and bops store, but they unfortunately did not have a 3.5mm stereo to 1/4" mono adaptor. Along the way, I've picked-up a Rode VXLR Mini-Jack Female to XLR Male Adapter -- haven't had a chance to try it yet, but wondering if it might do the same trick. If not, I might need to test some combinations and splice some wires together to make my own stereo to mono wire.

Geoffrey Kolbe -- Hmm... Maybe I need a pre-amp...

BazzBass -- All we wanted to do was to record some phone interviews as clearly as possible, and I was hoping the DR-40, an XLR mic and a 3.5mm stereo to 1/4" wire was all we'd need... Now I'm looking at a XENYX 502 5-Input 2-Bus Mixer and wondering it it's the missing piece.

Again, I'm very grateful for all of your help. It's nice feeling like there are some folks out there who know (muhc) more than I and who are willing to take a few minutes to straiten me out. Cheers!

 

[tzdvl]

The Rode VXLR Mini-Jack Female to XLR Male Adapter is NOT what you need. It just substitutes the male XLR for the 1/4 inch TRS connector. You'll get the same results as before.

What you can do, if you can't find a 3.5mm stereo to 1/4" mono adapter, is to combine TWO adapters:

Either combine a 3.5mm stereo to 3.5mm mono adapter, plugged into a 3.5mm mono to 1/4" mono adapter,

or use a 3.5mm stereo to 1/4" stereo adapter, plugged into a 1/4" stereo to 1/4" mono adapter.

However you do it, what you need to do is to connect the two stereo (L and R) outputs together to get a mono (L+R) output, by shorting together the tip and first ring contacts. THEN convert that mono (L+R) output to the 1/4" size plug.

By the way, we're replying to a different thread here than the one you started.

 

[DaveR514]

D'oh! Too many info-rich threads open in too many tabs...