Differences Between H1 and H2 models

Audio

At a glance, hardware-side, both models feature a headphone connector and the same AK4951 AUDIO / CODEC IC (You can get the datasheet following this link).

The AK4951 includes separate pins for speaker and headphone output:

• Pins 20 (SPP) and 19 (SPN) labeled as SPeaker Positive and SPeaker Negative (1W 8 ohm)
• Pins 22 (HPL) and 23 (HPR) as in (HeadPhones Left, HeadPones Right) (16 ohm)

Upon close inspection, several differences arise:

Audio in H2 model

Portapack H2 circuitboard includes a connector header for easily adding an internal speaker.

The AK4951 IC is rotated 180º and placed more into the middle of the circuit board, allowing for the addition of an extra IC: The ChipStar brand CS8122S ultra-low EMI, filter-free, class-D amplifier, for driving the speaker output with up to 3W.

The speaker audio header is switched on/off by the headphone female connector, which includes the usual switch, detecting the insertion of a male plug in it.

Audio in H1 model

The soldering pads for an internal speaker connector header are present. The speaker +/GND signals on the pad are routed directly into AK4951 pins.

NOTE: There is no extra amplifier IC between the speaker pad and the AK4951. The AK4951 includes a speaker amplifier capable of 1W, when powered @5v.