Headphone distortion when monitoring DR-40

[tzdvl]

Just trying to keep it simple...

All things being equal (never true, of course with audio gear ),
headphones between 100 and 300 ohms should be an easy load for the DR-40’s output amp, and should minimize frequency response irregularities.

Of course, some headphones have higher sensitivity than others (more dB for a given mW output), but with 20 mW available, the DR-40 should be able to make plenty of noise with most phones!

 

[Cosmic]

The overriding problem with a headphone out that is lacking in bandwidth and power is that, while it will tell you "you're getting a signal", it will not give you any idea about, say, low-freq rumble on-location...you are just getting a mid-range, underpowered representation of "reality" in front of the mics, which can be very deceptive, depending on circumstances.
Hence my suggestion of using a small rechargeable, better-quality headphone amp attached to the recorder. In my case, the amp is fed by the Line Out of the Tascam.

 

[Art Anderson]

I "re-discovered" this review of the DR-40 by Mike Rivers who has been published many times on all things audio.

Headphones and line outputs share an unbalanced mini jack. Maximum output voltage into a line input (10 kΩ or higher) is 1.5 Vrms (+6 dBu), a bit on the skimpy side for connecting to pro gear. 60 to 100 ohms seem to be the optimum headphone load, providing a maximum of about 15 mW at under 0.1% THD and adequate volume with most headphones.
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You might want to read the full review plus find other gear of interest by starting at this URL
https://mikeriversaudio.wordpress.com/product-reviews/