Alright guys, I've been A/Bing for hours, going back and forth between the Vsonic VSD3S and the iBasso IT01. First thing I had to do was find two pairs of tips that gave me about the same sound and amount of bass just on the VSD3S so that I could put one pair on the IT01 and give fair comparison without having to remove the tips from one and keep putting them on the other. Now that I've done my testing, I found my favourite tips which gives me maximum low end response.
rids, I know what you mean about the loose cable. In use though it's absolutely fine and stays uniform along the length.
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Before saying anything else, it's worth noting for you rids and Samyboy this which I quote from someone on head-fi:
"the a73 is warmer and to my ears has a little more natural, analog-sounding tonality; the IT01 has better-etched bass, a bit more treble emphasis and might be a little more coherent overall, although again they are quite similar, as both are full-sounding, immersive and have excellent instrument separation. in terms of quality, they're a coin flip-"
So here's my thoughts on the iBasso IT01. I don't really understand much about things like upper mids, mid bass hump, sparkle, etc so I'll just describe as best I can. I've only been testing them since last night so I know they have hours of breaking in to do. I don't know what improvements that brings and I think they sound great right now. I've got them connected to my laptop via my FiiO E11K with the FiiO gain switch on high. Sounded good with low gain but the high gain is where it's at for me, really drives the sound better. I also tried with the bass switch on but it's kind of unnecessary when the gain is on high. It adds a bit more weight to the bass but borders on overkill and muddying it up.
Also tested directly to laptop and sounds very good. Not much difference but I think the FiiO possibly cleans up the sound a little.
Actually, correction on that sentence, it's much crisper and more revealing with the Fii0.
I only have my Vsonic VSD3S to compare to, I don't know what the A73 sounds like. Tthank goodness the right ear didn't completely lose connection yet so I could compare. Let me first say I still think the VSD3S is a fantastic iem and that these are a very worthy upgrade.
Not the easiest to see which is the left and right earphone on the black ones even though it's faintly printed on, but I can tell which is which now. They're definitely a bit louder than VSD3S. The VSD3S to me have really good soundstage, good amount of detail and good bass. These are even better. Both iems are very comfortable. The IT01 fit my ears very nicely which I'm pleased about as I read some people have problems with that.
Of all the tips included, only the large ones give me proper bass. Neither of the foam ones give me bass. In the end, my favourite tips are these silicone ones I've circled. They're large but slightly flatter profile and have the largest holes.
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Really enjoying the IT01 so far! Here are the songs I tested. All from youtube so obviously compressed but they're pretty high quality, and for me, it's a fair comparison against the Vsonics as I mostly listen to music on youtube. If you listen to only one piece below, make it the Bill Meyers one.
Bill Meyers -images- Voyager Prelude & Liftoff. This a part classical, part jazz fusion piece. Incredible composition with world class players. I think it makes for a great iem test track and it's more than well presented in the IT01 to my ears. This is the first piece of music that made me notice how good the mids are compared to my vsonics. The horns sound incredible and the thing that really got my attention is I could hear the raspiness of the trombone, it has a lot of bite/edge/attack. I didn't really notice it on the Vsonics, it was there but soft, but on these it stands out beautifully, like wow.
The bass drum has such a solid deep thump but not muddy and still has the initial transient attack/slap of the beater on each stroke. The guitars are very present, slightly left of centre. Lovely sprinkling of glockenspiel that again, is more forward and stand out on these more than my vsonics. Amazing imaging, wide soundstage. Bass guitar has a warm tight sound, low enough and some detailed crisp slap bass moments.
John Mayer - Gravity. Bass drum super deep and punchy. Warm full sounding bass guitar. Vocal very close to my face, like being in the studio with him. Crisp and clear. Guitars again slightly left of centre, nicely imaged and upfront, compared to being a bit recessed with the Vsonics.
Gregory Porter - Holding On. Just gorgeous! It's a stunning ballad so sounds good on anything but it's even nicer on these. Nice soundstage here. Piano is the main instrument here with luscious chords soothing your soul. Light snare drum work keeping the groove, underpinned with a gentle bass drum. Little details like tambourine stand out that I didn't really notice on the Vsonics. Miles Davis style trumpet in the instrumental break is crisp and detailed.
Massive Attack - Angel. Bass heavy track. These handle the sub bass brilliantly, ear canal shaking for me. Love it.
Knower - Time Traveler. I guess this would be called electronica. Sounds very powerful on these with some serious sub bass notes.
Knower - Hanging On. Love this song. Drum sound is fairly heavily studio compressed, sounds fat on these earphones.
Overall I would say they're very detailed, full sounding iems with excellent bass and mids, and to my ears, nothing shrill or silbilant with the treble. if you were coming from a very cheap earphone, these would be utterly jaw dropping. But coming from a good quality earphone like my Vsonics, it's not so much jawdropping although there are some jawdropping moments, but certainly astounding resolution which makes them very very enjoyable to listen to.