I think it’s as simple as the change in overall load resistance is changing the curve for the treble-de-emphasis circuit in the interface. Half an ohm is significant when the total load is only 0.018 to begin with.
You can get the same effect simply by bypassing resistors in the interface, and as fewer are included (resistance reducing) the progressive treble-roll off becomes greater. This results in a slight rise in response from about 200Hz (up to about 0.3 dB by 500 Hz, then swinging gradually down through about 1.5 kHz all the way into ultra sonics.
Thinking about it more last night, I am just going to leave such switching to my enhanced interface box. The changes just switching the resistors in there will give about 3 dB total adjustment by 20 kHz and progressively steeper roll-off earlier in the spectrum.
@Zhanming057 has posted a graph of the result of doing this in the interface, possibly from Alex, somewhere … I’ll see if I can find it.
I figured I’d pick them up as an “completely different alternative”, piddle with a few progressively-specced/priced amps to see how they did (mostly from a review perspective), and then just add the SPL Performer s800 to my Phonitor X chain (fed from DAVE and the RME ADI-2 DAC) and call it good.
Well, they say “no plan survives first-contact with the enemy” … and that was certainly the case here …
I am enjoying power-amp adventure and really surprised with how sr1a picked up small changes over gears in a less aggressive way (HD800, non-S, for example, was very amp-picky presenting either happy or miserable result).
SR1a is never a difficult load. Required power is compatible with efficient speakers at practical distance AND impedance changes over frequency remains rather stable (compared to really difficult speakers such as Apogee or Magnapan). This likely played an important role to enjoy any amp connected.
The more I enjoy this adventure, the more I feel urged to get a smaller and lighter carrying case.
Every change from vidar was associated with perhaps meaningful gains … but much more unbearable losses as well. No free lunch at all. I began to think msrp the least determining predictor for the overall performance. Also rated power was persistently insignificant to me. Good quality over 0.1-10W range is way more important. Exceptionally high biasing point (1W) of vidar also distinguishes itself from most class-ABs (100-250mW) in production.
That said, if I upgrade amp for sr1a, it would be either sub-50W class As or constant-gm ABs.
Very unfortunately, I am concluding SR1a an eq-must headphone for my perception. I initially thought eqing track-dependent, but later found it generally benefit myself.
Great thread enjoying it immensely. I am holding off on buying the SR1a 1) until taxes are filed this year (I did an extension) so I know how much hobby money I have to burn and 2) a clearer consensus on the best performance for price amp is reached.
I assumed I would just get a single Vidar and go from there. However @Torq do you have a Performer s800 coming it? I would be interested if you like the s800 as much as @MrCypruz does. If the s800 really is an end game amp for the SR1a I could buy one with bitcoin.
They were not available in the US within the period for which I needed in order to make an evaluation (for my own purposes). I am not going to ask a dealer to bring one in for “demo” where I have no intention of buying one at this point, either.
That said, I expect I’ll get to give the SR1a a run with one this weekend at the Vancouver meet.
Definitely a good starting point, as it is inexpensive and the most widely agreed common denominator. Use this as reference to try alternatives and find more upstream amps to your liking at the preferred price points.
…and it could very much be your end game if you don’t get bitten by the upgraditis bug!
As I said on my previous post, the Performer s800 is not $2,500 better than the Vidar. The s800 analog liner toroidal transformer is a 855 VA vs 600 VA on the Vidar and the 120 V Voltair technology might also play a significant role on the s800 performance. If it wasn’t for the deal that I got on the s800, I would have most likely settled with a single Vidar with the potential of adding a second one later on. Two Vidar mono blocks may perform on par with a single s800 (if not better, just guessing here) and they still come out way cheaper than the s800.
Don’t rush. Stax has its own benefit. 009 has its own merit and unique sounding in Stax way. Some like Raal, others like Stax. All understandable. Haven’t heard 009S yet (owned 009 non-S before) though.
Honestly, I can’t comfortably recommend either 009 or SR1a. Each sucks to some extent. Preference and taste really matter.
Until ~30 days or so ago I owned the EE Zeus XR (A) … and used them as my “neutral reference” IEM (for raw “enjoyment”, I prefer my tia Fourté …).
The SR1a does stage, scale, impact and speed better than the Zeus XR(A). And … I’d give the edge to the SR1a in terms of resolution/detail also. Though, of course, you don’t need to lug a 20+ lb box of metal around to get those abilities out of the Zeus (any version).
The SR1a are the first “headphone” I’ve come across that truly rivals (and, in my opinion, exceeds) the resolution and immediacy of TOTL IEMs. And … stage blows any IEM away … even the best Apex/ADEL equipped IEMs …
I do think there exists similarity between SR1a and Apogee (can’t remember which model I heard) in treble presentation. So, it sounds more reasonable for you to try SR1a. haha.
But let me just comment that unequalized SR1a could be brighter than 009, depending on which treble range to feel more sensitive. SR1a has more solid and deeper bass, midrange is a little more wet and liquid-ish with 009 (paired with SRM717) from the memory, and top end extension is nearly on par but I prefer Raal. Without considering equalization, I would take 009 for modern and treble-heavy tracks (SR1a gave me really hard time for such tracks) and SR1a for naturally-mic’d jazz or darker vocal works.
I would recommend both of them everyday and twice on Sunday granted that you’ve proper DAC and amplification (KGSSHV Carbon - I’m using this one / Carbon CC / KG T2 / BHSE for Stax and Performer s800 for SR1a) and be done with the headphones…but that’s just what my ears told me.
Ah and I truly enjoy both headphones without any EQ at all.
I initially thought eqing track-dependent, but later found it generally benefit myself.
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