Sound:
I always used and use my SE425 with source devices that have a (very) low output impedance, whereby a slightly higher output impedance of the source device, as for example with an Apple iPod Classic 7G, does not necessarily negatively affect the in-ear and raises the high frequencies a little.
In the early days I used the black foam tips from the included kit, but at some point I started to use the biggest grey silicone tips included, which I still use to this day.
Tonality:
If you're looking for a rather neutral and linear sounding in-ear, the SE425 might be just the thing for you.
In terms of neutrality, the Shure tends towards the Etymotic ER-4S/SR and presents a largely sterile, flat and uncoloured sound with a mostly flat bass range, but without an emphasis on the presence range.
Compared to the Ety, however, the Shure has a touch of warmth in the fundamental/lower midrange, which is definitely little enough that it doesn't make the Shure sound even slightly thickened or "cuddly warm" in the low frequencies.
The SE425 can also reproduce real sub-bass with sufficient level, but it has a gentle decline from the fundamental range towards it, which is why there is less pressure from the very low frequencies.
The midrange of the Shure is neutral except for the gentle boost in the fundamentals and appears only minimally warm and dark when compared to an in-ear like the Ultimate Ears Reference Monitors, as there is slightly less level in the presence range than there could be to have a completely flat midrange.
Due to the mild roll-off towards low bass and the relatively early roll-off of the high frequencies, the impression can also arise that the Shure tends to be assigned to the mid-centered side of neutral in-ears.
The Shure's treble remains unobtrusive in the positive sense in the lower and middle highs and has no unevenness or peaks, but plays relatively neutral with a moderate dip in the middle highs compared to the Etymotic ER-4S/SR or the UERM.
A pity, and thus the biggest weakness of the SE425, is the fact that the Dual-BA In-Ear starts to roll quite early and quite steeply in the upper treble, which is why cymbals are missing in body as well as in decay, and some instruments are audibly lacking in overtones ("air"). Due to this relatively early roll-off, the upper treble appears correspondingly cut and it lacks presence, glitter and resonance, which is a shame, because otherwise the Shure is a mostly natural and authentic sounding in-ear.
Resolution:
The resolution level of the SE425 is rock solid for a multi-BA in-ear in this price range and surpasses the level of details of most similarly priced in-ears with dynamic drivers. Nevertheless, the Shure is definitely not the class leader among the Multi-BA In-Ears in its price range - the Rose Technology Mini2 as well as the Brainwavz B200 (first generation), just to name two, (the latter, however, is clearly less neutrally tuned) offer the somewhat higher detail resolution despite their lower price, while the Etymotic ER-4S, which you could now also get for 200 to 250$, also has the higher detail resolution. Another in-ear that is largely neutral/balanced and beats the Shure at a lower price is the Pai Audio MR3, whose resolution level is about the same as that of the more expensive InEar StageDiver SD-2.
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The bass of the SE425 is very fast, tight and clean. You won't find softness or sponginess in the SE425 and single punches as well as more complex bass lines are reproduced cleanly separated from each other. Here, the SE425 can even outperform some multi-BA in-ear drivers with rear-vented BA drivers in terms of tightness.
The midrange also leaves no room for criticism when it comes to detail reproduction for the price, and convinces with good speech intelligibility.
The Shure's treble doesn't lack details either, but the early and steep roll-off in the upper highs doesn't make it look that good.
- - -
Overall the Shure delivers a convincing and more than solid performance for the price, but has to admit defeat to some other, cheaper Multi-BA In-Ear in terms of the overall detail resolution, whereby it should also be mentioned that those models are mostly "exotic", and have to be imported from Asia.
Nevertheless: with the existing competition, a price of the SE425 that is closer to 200$ than to 300$ is clearly more justified, because for a little more than 300$ you already get quite neutral Multi-BA In-Ears that outperform the Shure in terms of detail resolution by more than one class and offer the much better tweeter range.
If you are looking for an in-ear that is largely neutral or even tends to be emphasized in the midrange, the Shure below 250$ is still a good choice, as most of the competition is not quite as neutral as the American IEM, even though its high frequency range is quite limited. And those who can live without the same level of neutrality will still find very well-balanced and technically even more convincing models in the competition.
Soundstage:
The stage of the SE425 is (very) small and especially narrow. I would even say that it has more spatial depth than width. As far as some owners of the Shure think, it has practically no stage at all, but I would definitely not go as far to say that since it has a more pronounced three-dimensionality than my Sennheiser Amperior, which is however not a hard thing to achieve (at all).
In terms of instrument separation, the Shure performs well, although there are also more open and spatially better separated models here.
The layering on the Z-axis, on the other hand, is good again.
Conclusion:
The Shure SE425 is a good/solid choice for anyone looking for a neutral in-ear with a midrange preference. As far as neutrality is concerned, only rather few in-ears come close to the American in-ear around the same price. Nevertheless, it is of course not free of limitations and thus has only got moderate-at-best treble extension and a rather small and narrow soundstage.
For $220 to $260 I consider it a very solid but not perfect product if you want to get a neutral in-ear.
More than 270, maximum $300, would definitely be too much for the Shure to me these days, as there are already technically noticeably better alternatives for a little more than $300 and there are also exotic models in the lower price range that reach or even exceed the technical performance of the Shure.
I always used and use my SE425 with source devices that have a (very) low output impedance, whereby a slightly higher output impedance of the source device, as for example with an Apple iPod Classic 7G, does not necessarily negatively affect the in-ear and raises the high frequencies a little.
In the early days I used the black foam tips from the included kit, but at some point I started to use the biggest grey silicone tips included, which I still use to this day.
Tonality:
If you're looking for a rather neutral and linear sounding in-ear, the SE425 might be just the thing for you.
In terms of neutrality, the Shure tends towards the Etymotic ER-4S/SR and presents a largely sterile, flat and uncoloured sound with a mostly flat bass range, but without an emphasis on the presence range.
Compared to the Ety, however, the Shure has a touch of warmth in the fundamental/lower midrange, which is definitely little enough that it doesn't make the Shure sound even slightly thickened or "cuddly warm" in the low frequencies.
The SE425 can also reproduce real sub-bass with sufficient level, but it has a gentle decline from the fundamental range towards it, which is why there is less pressure from the very low frequencies.
The midrange of the Shure is neutral except for the gentle boost in the fundamentals and appears only minimally warm and dark when compared to an in-ear like the Ultimate Ears Reference Monitors, as there is slightly less level in the presence range than there could be to have a completely flat midrange.
Due to the mild roll-off towards low bass and the relatively early roll-off of the high frequencies, the impression can also arise that the Shure tends to be assigned to the mid-centered side of neutral in-ears.
The Shure's treble remains unobtrusive in the positive sense in the lower and middle highs and has no unevenness or peaks, but plays relatively neutral with a moderate dip in the middle highs compared to the Etymotic ER-4S/SR or the UERM.
A pity, and thus the biggest weakness of the SE425, is the fact that the Dual-BA In-Ear starts to roll quite early and quite steeply in the upper treble, which is why cymbals are missing in body as well as in decay, and some instruments are audibly lacking in overtones ("air"). Due to this relatively early roll-off, the upper treble appears correspondingly cut and it lacks presence, glitter and resonance, which is a shame, because otherwise the Shure is a mostly natural and authentic sounding in-ear.
Resolution:
The resolution level of the SE425 is rock solid for a multi-BA in-ear in this price range and surpasses the level of details of most similarly priced in-ears with dynamic drivers. Nevertheless, the Shure is definitely not the class leader among the Multi-BA In-Ears in its price range - the Rose Technology Mini2 as well as the Brainwavz B200 (first generation), just to name two, (the latter, however, is clearly less neutrally tuned) offer the somewhat higher detail resolution despite their lower price, while the Etymotic ER-4S, which you could now also get for 200 to 250$, also has the higher detail resolution. Another in-ear that is largely neutral/balanced and beats the Shure at a lower price is the Pai Audio MR3, whose resolution level is about the same as that of the more expensive InEar StageDiver SD-2.
- - -
The bass of the SE425 is very fast, tight and clean. You won't find softness or sponginess in the SE425 and single punches as well as more complex bass lines are reproduced cleanly separated from each other. Here, the SE425 can even outperform some multi-BA in-ear drivers with rear-vented BA drivers in terms of tightness.
The midrange also leaves no room for criticism when it comes to detail reproduction for the price, and convinces with good speech intelligibility.
The Shure's treble doesn't lack details either, but the early and steep roll-off in the upper highs doesn't make it look that good.
- - -
Overall the Shure delivers a convincing and more than solid performance for the price, but has to admit defeat to some other, cheaper Multi-BA In-Ear in terms of the overall detail resolution, whereby it should also be mentioned that those models are mostly "exotic", and have to be imported from Asia.
Nevertheless: with the existing competition, a price of the SE425 that is closer to 200$ than to 300$ is clearly more justified, because for a little more than 300$ you already get quite neutral Multi-BA In-Ears that outperform the Shure in terms of detail resolution by more than one class and offer the much better tweeter range.
If you are looking for an in-ear that is largely neutral or even tends to be emphasized in the midrange, the Shure below 250$ is still a good choice, as most of the competition is not quite as neutral as the American IEM, even though its high frequency range is quite limited. And those who can live without the same level of neutrality will still find very well-balanced and technically even more convincing models in the competition.
Soundstage:
The stage of the SE425 is (very) small and especially narrow. I would even say that it has more spatial depth than width. As far as some owners of the Shure think, it has practically no stage at all, but I would definitely not go as far to say that since it has a more pronounced three-dimensionality than my Sennheiser Amperior, which is however not a hard thing to achieve (at all).
In terms of instrument separation, the Shure performs well, although there are also more open and spatially better separated models here.
The layering on the Z-axis, on the other hand, is good again.
Conclusion:
The Shure SE425 is a good/solid choice for anyone looking for a neutral in-ear with a midrange preference. As far as neutrality is concerned, only rather few in-ears come close to the American in-ear around the same price. Nevertheless, it is of course not free of limitations and thus has only got moderate-at-best treble extension and a rather small and narrow soundstage.
For $220 to $260 I consider it a very solid but not perfect product if you want to get a neutral in-ear.
More than 270, maximum $300, would definitely be too much for the Shure to me these days, as there are already technically noticeably better alternatives for a little more than $300 and there are also exotic models in the lower price range that reach or even exceed the technical performance of the Shure.
