Topic: Tascam FR-AV2 new compact 32bit float recorder.

[Gutbucket]

Anyone using a more sensitive microphone for music/concert recording is crazy.

That's apparently what the manufacturers of 32-bit recorders think.   If the marketing angle is that any mic can be plugged in with no need to set gain, you'd think they'd include a switched pad to avoid overloading the input stage.

[commongrounder]

Anyone using a more sensitive microphone for music/concert recording is crazy.

That's apparently what the manufacturers of 32-bit recorders think.   If the marketing angle is that any mic can be plugged in with no need to set gain, you'd think they'd include a switched pad to avoid overloading the input stage.

This is what I like about the Zoom F3, and put me off of the FR-AV2. The input mode selection has line-in *with* phantom power on as a choice. The line-in is a -20dB pad, built in, no external pads required. I use Sennheiser mkh series mics which have high output. High SPL sound sources are easy to cleanly capture with the mkh/F3 combo.

[TheJez]

I still don't understand the narrative that the inputs are easily overloaded. A microphone with a sensitivity of 12 mV/PA (ex.Schoeps CMC6) will not output 4 dBV until the sound pressure hits 134 db. Anyone using a more sensitive microphone  for music/concert recording is crazy.

My SP-CMC-4U (XLR Phantom) mics have a specified sensitivity of 11.2mv/PA, yet still easily overload my FR-AV2 inputs, even for very moderately loud shows. I got myself a pair of attenuators to prevent this from happening again. Not sure if my FR-AV2's inputs are more sensitive than they should be, or if my mics are more sensitive than specified, or something else...

[TheJez]

I'm very new to recording, so if I use mics with SPL max 130dB (connected through EXT/IN), would +4 dB be good setting on FR-AV2 at loud concert? Or Should I still monitor it and adjust while recording?

What do mean with 'would +4 dB be a good setting'? Do you mean setting the 'record level' to +4 dB, or setting the record level to aim for +4dB peaks on your VU-meters?

FYI: The FR-AV2 has a fixed analog gain. Then, after doing the analog-to-digital conversion, a selectable (0..+60dB) amplification is done. This is what is called the 'Record Level' in the user interface.
My take:
1) Make sure your mics can handle the maximum sound pressure levels to be expected at your intended recording situations (your 130dB max SPL seem fine in that respect)
2) Indeed, make sure that your analog input is not overloaded (i.e. too sensitive mics / too loud music). Solutions if you overload: Take more distance from the sound source, get less-sensitive mics or use attenuators.
3) Actually, when recording in 32bfp format, setting the 'record level' doesn't really matter at all. It won't change the analog gain, so won't affect the signal/noise ratio. You can always amplify/attenuate the recording afterwards without any quality loss. In this case it doesn't matter if the peaks are above 0dB or not. (If you'd like to play the recording directly from the device, e.g. during the car trip back home, it would be nice if it was recorded at decent levels. You may set the 'record level' to achieve that. Yet leave the record level untouched during recording as it will change the volume of your recording...!)
4) If you'd be recording (for whatever reason) to 24bit format, you must make sure that the peaks won't go over 0dB, as the file format cannot store that! If the 'record level' is set such that the peaks will go over 0dB, you will get digital clipping. The gain of the analog input is fixed aswell in 24bit mode...

What microphones are you intending to use? And what type of shows will you be recording? That might help determining if analog input overloading or may be applicable for you or not...

[Gutbucket]

[snip..] Not sure if my FR-AV2's inputs are more sensitive than they should be, or if my mics are more sensitive than specified, or something else...

One "something else" (which may or may not be the case here) is crest factor, which is a measure of dynamics.  It's the ratio of peak level verses average level, and varies significantly depending on what you are recording and the recording position.  For instance, onstage near a drum kit the crest factor is very high. You'll get much higher peaks there than at a recording position out in the audience where you're primarily picking up the PA, despite the average level (which is what correlates more closely with the perception of "loudness") being similar in both locations.

[TheJez]

[snip..] Not sure if my FR-AV2's inputs are more sensitive than they should be, or if my mics are more sensitive than specified, or something else...

One "something else" (which may or may not be the case here) is crest factor, which is a measure of dynamics.  It's the ratio of peak level verses average level, and varies significantly depending on what you are recording and the recording position.  For instance, onstage near a drum kit the crest factor is very high. You'll get much higher peaks there than at a recording position out in the audience where you're primarily picking up the PA, despite the average level (which is what correlates to the perception of "loudness") being similar in both locations.

That's a good call, and possibly the culprit. The show wasn't loud at all, yet I was standing belly-to-the-stage (see https://www.youtube.com/watch?v=6Mw0_5OoWuo), about 1.5 meters from the PA and about 4 meters from the drumkit. The (fortunately just very slightly distorted) peaks were the kicks on the base drum. Not sure if these were the very marginally amplified kicks or the 'live' kicks straight from the drumkit (or a combination).
Generally I like recording close to the PA, for the dry sound and the music/crowd noise ratio. Apparently I need those attenuators to reliably accomodate that with my mics. As mentioned earlier by commongrounder, it would have been great if the FR-AV2 could enable phantom power when input is set to 'line in' (like the F3 does), but it doesn't. I wonder if this is a limitation of the electrical design or if it's something that could be changed by a firmware update...

[Gutbucket]

^ That looks close enough to get strong peaks directly from the drums, making for a nice "lively" sound. [edit after listening- however the playing in that particular clip does not seem energetic enough to peak and potentially clip any more than audience reaction by the folks in close proximity to you]

Less common yet something else to be aware of when recording close to drums is that there can be a sort of localized pressure wave relatively close, low and directly on-axis with the kick drum, sometimes even manifesting as direct "puffs" out the hole in the front skin, if there is one.  Partly for that reason I try to setup slightly off-axis from the kick, slightly toward the snare side if possible.

Using high sensitivity mics when recording onstage where crest factor is high I absolutely need to engage the advanced limiter on the Zoom F8. That's the only way to engage its -10dB pad, going Mic-in, and there is no phantom power available on Line-in, corrected on later models.

[gmm6797]

I once scored nice front-row tickets to a show in a venue I had never been to before. Well, guess what.... I have a recording of Slash's amp, and thew singer talking between songs... the PA was actually hung behind the pit so I got about 2% PA and 98% Slash's amp... needless to say, I never converted it

[datbrad]

I don't know if this is relevant, but the sensitivity specs for the AT capsules in the SP setup are "open circuit", which is the output with no load and the standard way sensitivity is expressed for dynamic mics. Electret condensers are able to output a signal without any polarization voltage on the capsules. This might mean the sensitivity if measured at the XLR end with power applied is much greater. That could explain what the  poster using the SP setup experienced. DPA and Earthworks use pre-polarized capsules in all their mics, and the sensitivity is measured at the mic output, after going through the preamps in the mic bodies. Just a thought....

[morst]

I once scored nice front-row tickets to a show in a venue I had never been to before. Well, guess what.... I have a recording of Slash's amp, and thew singer talking between songs... the PA was actually hung behind the pit so I got about 2% PA and 98% Slash's amp... needless to say, I never converted it

if you ever find a SBD recording of that show it might make a good mix

[gmm6797]

I once scored nice front-row tickets to a show in a venue I had never been to before. Well, guess what.... I have a recording of Slash's amp, and thew singer talking between songs... the PA was actually hung behind the pit so I got about 2% PA and 98% Slash's amp... needless to say, I never converted it

if you ever find a SBD recording of that show it might make a good mix

Good point, but I am not holding my breath 10+ years later lol

[adrianb]

I took my FR-AV2 to a gig at the weekend. It was my mates band and they asked me to record it. I was running DPA 4061 mics into it with 5V PIP, which I’ve done numerous times previously. Unfortunately, at the end of the 2 hour gig when I examined the recorder I noticed there was only a single recording of 15 mins. It seems that the recorder shut itself down after 15 mins.

(Fortunately I also went with my new purchase of the Zoom Pro C Stereo Instamic which I was testing and produced an acceptable recording)

The next day I examined the recorder and settings, and tested another recording with the same batteries which showed full charge on the recorder, and this time the recorder switched down after just 3 minutes.

I then put in some fresh batteries and this time the recorder seemed okay.

I’m thinking that one of the batteries is faulty, but it’s concerning because they were freshly charged before using and the recorder indicated full charge.

[Gutbucket]

Sounds like NiMH batteries at end of useful life.  Internal resistance increases as they age, choaking available current.  Voltage will measure okay after recharge prior to use, but will drop quickly in use. 

If you can, its good practice to get into the habit of checking voltage of the batteries under load at the end of each recording outing.  That way you can catch it and switch to alternate batteries before loosing a recording.  Upon implementing that I've not lost any recordings from old NiMH hatteries failing.

You may be able to run a refresh cycle on the charger if available to wring some more life out of them, but then best to then use them for non mission-critical stuff only where it won't matter when they fail.