Phonak Sky aka Naida M70 SP & Phonak Naida P70 UP - Low Frequency Range

[Zebras]

I’ve got both the M70 SP and P70 UP and the audiologist said when doing REM that the lows in the SP can’t go as high as they are on the UP for what I need.

Is that due to the fitting range or something else?

Fitting ranges below.

SP range -

UP range -

[eyesgreendeaf]

My guess is that this is related to technical limitations of SP receivers.
@Um_bongo can give more insight
As a former user of SP aids, I think they are not powerful enough for very profound losses. I feel the difference with my current UP aids

[Um_bongo]

It’s just the physical diaphragm size and power. The UP all used to use a Knowles CI receiver which is a fairly big chunk of kit. If you want to move a lot of air in lower frequencies you need a lot of power.

Smaller receivers just can’t drive that kind of SPL at lower frequencies.

[Terost]

It’s the difference of the receivers or some will say speakers. I have both the V90 SP and the P70-UP aids.
The Nadia Paradise has two receivers inside the aid while the SP has an smaller receiver. It’s why l get more gain with the P70-UP than the V90 SP aids. Also the amplifier is different in these aids.