Curious if anyone can lend some insight on the following:
PCM A-10 AUDIO in specifications:
Input impedance: approx. 4.7 kΩ
Rated input level: approx. 2 VMinimum input level: approx. 18 mV
Tascam FR-AV2 max input specifications:
XLR/TRS LINE level:
24 dBu
3.5MM:
+1 dBV
In trying to shortcut understanding these values, I plugged them into Claude and asked for some details translating them. I came out with the following:
+1 dBV (FR-AV2 3.5mm jack) = 1.122 volts RMS
+24 dBu(FR-AV2 XLR/TRS jack) = 12.28 volts RMS
+8.2 dBu(PCM-A10 LINE IN) = 2.000 volts RMS
Does this seem right? I'm trying to understand the practical applications as it relates to an increase or decrease in headroom, using some DPA 4061s into the FR-AV2 3.5mm as opposed to the PCM-A10. At this point all I know is "well, one of those numbers is bigger than the other!", but in terms of practical applications, with the goal being "I don't want to have to worry as much about digital peaking in my recording device", I'm trying to gain further understanding.
Seems that I may be best served using something like this?
https://immersivesoundscapes.com/accessories/Adapter-for-PIP-mics-to-work-on-XLR-48V-Recorder-p492004466Do the benefits afforded by dual ADC outweigh any concern related to max input with those values?
These are the questions I'm asking myself and attempting to research and understand. Just wanted to pose the question here in case anyone is able to quickly lend some insight. These values and what they mean are a bit of new territory for me.
edit: Here's the conclusion I'm running with for the time being. Will ultimately test both in the field side by side. If anyone wants to chime in with why this is bullshit or correct, feel free. Just output from discussions with LLM (Claude)
To answer this question, we need to compare the maximum input levels and the recording technology of both devices:
PCM-A10 LINE IN: +8.2 dBu (2.000 volts RMS)
FR-AV2 3.5mm jack: +1 dBV (1.122 volts RMS)
At first glance, the PCM-A10 appears to be the "safer" choice because it can handle a higher input level before clipping in its analog stage. However, this doesn't tell the whole story. Let's break it down further:
FR-AV2 advantages:
32-bit float recording: This provides an enormous dynamic range, theoretically capturing everything from the noise floor to well above 0 dBFS.
Dual ADC system: One ADC captures the full range, while another captures at a lower gain, providing a safety net for unexpected peaks.
PCM-A10 limitations:
Traditional fixed-point recording (likely 16 or 24-bit).
Single ADC system.
Why the FR-AV2 might be safer despite the lower maximum input level:
Even if the analog input stage clips, the lower-gain ADC in the dual system can still capture the peaks accurately.
The 32-bit float format allows for extreme gain adjustments in post-production without introducing quantization noise.
You have more flexibility in setting levels. You can set a lower input gain to avoid clipping the analog stage, and still capture quiet details thanks to the high bit depth.
In practical terms:
With the PCM-A10, if you clip the input, that information is lost forever.
With the FR-AV2, even if you clip the analog input stage, you're likely to still have usable audio data that can be recovered in post-production.
Conclusion:
The FR-AV2 with its 3.5mm input would likely be the safer choice, despite its lower maximum input level on paper. The advanced recording technology provides a much wider margin for error and more forgiving post-production options.
That said, the ideal solution would be to use the XLR/TRS inputs on the FR-AV2 if possible, as they provide even more headroom. If you must use the 3.5mm input, start with a lower gain setting than you would on the PCM-A10, and trust in the 32-bit float and dual ADC system to capture the full dynamic range of your source.
Remember to always do test recordings in conditions similar to your actual recording scenario to ensure you're getting the results you need.
