While SR1 looks excellent on paper and sounds good, especially with the bass that has potentials, I thought that it could perform even better if it is totally opened.  Therefore, I swapped in perforated pads.  The results were nothing but staggering.  It transformed SR1 into a more of an opened-back headphones with a much better open presentation, taking SR1 several levels higher when compared to stock out of the box.

I used these pads for my upgrade.

Here is a short tutorial how to swap SR1 pads:

One thing to note is that SR1 is not exactly easy to drive like iBasso suggested it to be.  Of course, you can drive it loud even with an iPad or DX200 with any amp modules.  But I think it will not do the SR1 justice.  Loudness doesn’t equal finesse.  It puzzles me why HD800S could be driven beautifully by DX200Ti and AMP8, but SR1 still has room for improvement out of the same system.  I had to hook it into the Mini-Dynalo amplifier, which is specialized in driving low impedance headphones.  Now, the SR1 is shining with high-end performance.  The following impressions are based on the best of what SR1 is capable of.

Bass: is very punchy, deep, and more balanced.  It has a nice bloom but with a crazy control, feels like a speaker performance in comparison to HD800S which I consider to be a more reference headphones.  The bass here reminds me of Utopia, only that the SR1 carries on that Wooly pronounced bass from bio-cell.  It is like the best of TH900 from Fostex.  Sub-bass is very deep, precise, very dynamic, just beautiful.  The bass quality can be said to be enjoyable next to Stax SR-009 out of the best system, such as T2-Amplifier.

Mids: The SR1 has a beautiful sweet, thick, organic mids.  It makes female vocals to be very seductive, and male vocals to be addictive.  Beautiful mid also show a very organic timbres for string instruments.  Together with the sweet, precise, controlled bass, the whole spectrum from lows into upper mids is very enjoyable, musical, organic, and realistic.

Treble: thicker, great speed, airy, crisp, and yet sweet and fluid.  There is no harshness or sibilance.  It could be spitting out sibilance with bad sources, but it’s more forgiving than HD800S.

Layering: is excellent, and I personally think that for dynamic headphones, the SR1 strikes a beautiful balance between realism of timbres, great dynamics, and separation.  The only way to make layering better would be by going off balance, making the timbres thinner, less realistic, more similar to HD800S.

The HD800S can have unsurpassed level of soundstage and layering, but its balance of timbres realism is a bit off.  I view HD800S as reference headphones, a scope to peek at the music.  In contrast, the SR1 is an enjoyable and musical Headphones that are not heavily overemphasized.

Here are more pictures of iBasso SR1 with new pads:

 

Conclusion.

Maybe it feels that I raved too much about SR1?  Not really, since I only give credit where credit is due.  Stock, out of the box, SR1 is not as impressive when compared to HD800S, especially without a good amplifier to show its strength.  It still lacks behind HD800S in separation and soundstage, but it can be said to have a better musicality and timbres realism.  It will come down to a personal preference.  But what surprised me the most is how the SR1 at $499 with upgraded pads can be competitive against a more pronounced Sennheiser HD800S, even with a different signature.

It is best paired with more neutral and slightly brighter amps.  The Dynalo is excellent, or GSX would also do it justice.

Finally, is it worth buying? Oh yeah, a big Yes for me!  Especially since I like iBasso and wanted to support the company in future developments.  At this price, in my opinion the performance is a steal for the money.  Also, don’t forget, it is a limited production of 500 units.  And I can’t wait what else iBasso is going to release in the future!