Serratus (300ohm PET) vs Serratus 2 (130ohm N55 driver) Impressions
Thanks to @AsciiJC for the opportunity to hear the S2
Serratus 2
Resin Bell 4.4mm (stock foams)
Serratus OG MX500 (stock foams)
Lotoo P6K 4.4mm high gain
Music: Jazz, classical, world music
Tonality - similar colouration overall
Bass
S1 has more subbass extension, midbass is much the same quantity, S2 has a cleaner procession into lower midrange
Midrange
S2 has a more forward, fuller midrange overall and with greater presence in the upper mids, S1 midrange is set further back and can feel slightly hollow, less intimate and less intense; Female vocals on S2 are more forward with better isolation and intelligibility than S1. On this resin bell version of S2 there is some mild shout at higher volume, S1 doesn’t share this issue.
Treble
S1 has a hints of metallic sharpness that cut through on some tracks making the treble feel unbalanced; S2 treble is similarly emphasised but without the sharp peak. S2 may have slightly more ‘air’.
Technicalities
Resolution - S2 brings out more texture and microdetail, I don’t feel S1 is actually that resolving, it just relies on the treble emphasis to make it seem so.
Soundstage - S1 has a perceptibly wider stage than S2 but this may just be because the midrange isn’t as emphasised. The S2 is more dimensional in staging, feeling more open on more axes, with more positional information between L-R channels within the headspace
Imaging - S2 images more definitively in space
Verdict (YMMV)
S2 takes the win on tonality and technicalities. Importantly, the S2 also takes the win on timbre, its tonality lends itself to revealing more detail and filling fundamental notes better. Thankfully the treble peak is gone but treble definition and detail is still retained. The custom S2 driver is performing technically better in many regards, it just lacks the very low end extension of the PET300. The S2 may be considered less of an all-rounder versus the original due having less subbass and a more intense midrange, however it performs far better on instrumental music than the original. The only shortcoming with the S2 is some shout/stridency in the upper mids that is volume dependent and is perceptible in some vocal performances (if you listen at moderate levels you will probably not have this issue).
N.B. this version is the resin bell version and the sound may not be an accurate reflection of the metal MX500 version
EDIT: corrected an error in the treble section- it was meant to read that S1 has a metallic sharpness in the treble, not S2.
