DAC, Preamp, Headphone Amp: Corda Soul and Oppo HA-1 (5 of 8)

Audio
by Mike Clements

This is part 5 of an 8 part series comparing the Meier Corda Soul and Oppo HA-1. Click here for the introduction.

Wed 12/26; LCD-2 headphones; direct, no EQ

  • New config for faster switching
    • Oppo BDP-83 coax output to HA-1
    • Oppo BDP-83 toslink output to Soul
    • Or reverse of the above; coax and toslink output levels match
    • Level matched using white noise & SPL meter (as before) to < ½ dB
    • Simply replug the headphones back & forth, nothing else
    • Both amps continually playing the same signal
  • Many of the above tracks played repeatedly… also
  • Bruce Katz; Three Feet off the Ground: an excellent Bernie Grundman master
  • Clementi; Demidenko; Helios
  • Doug MacLeod; Brand New Eyes; One Eyed Owl
    • This is a superbly recorded track deep, tight bass, light fast transients and near perfect natural vocal reproduction
    • Oppo & Soul almost the same, but the Soul had slightly deader space between the notes, tighter bass
  • Michael Hedges; Aerial Boundaries: fast transients with extreme HF
    • Soul & Oppo: equal speed, crisp transients
  • Tuck & Patty; Love Warriors; Little Wing
    • This is a nice recording, uncompressed and natural sounding
    • Soul & Oppo: sound the same, bass & voice have same timbre, bass plucks are equally fast & light
  • Julian Bliss Quartet; Hyperion:
    • Almost the same
    • Oppo slightly more air, Soul a touch more mid bass
  • Gillian Welch; Harrow & the Harvest: compressed but very detailed with subtle timbres
    • Both Oppo & Soul capture the very delicate shades of timbre in the voices, the guitar work and micro-detail of breathing & movement
  • Ronnie Earl; Maxwell Street: crunchy & compressed, how well do they portray a bad recording?
    • Oppo & Soul sound the same.
  • Dream Theater; Systematic Chaos: dynamically compressed but otherwise clear with full, wide bandwidth: how well do they rock out?
    • The Oppo has slightly more air, but the difference is so small I can’t be sure
    • Otherwise both sound the same: the bass hits down to 20 Hz, the midrange tonality, the layers of background detail, all identical.
  • Also played several tracks from Steven Wilson’s Yes re-mix
  • These are so similar that even for a picky detail-oriented guy like me, even if I could tell them apart in a blind test (not sure I could), I could love either one.
  • This is beyond splitting hairs. That said…
    • The Soul seems a bit more tight, pure, punchy
    • The Oppo seems to have more depth & breadth

Wed 12/26; speakers, direct, no EQ

  • New config for more fair comparison
    • Both players running as above (Oppo from coax, Soul from toslink, or vice versa)
    • Both preamps running in balanced mode (no more unbalanced Oppo output)
    • Swap the balanced XLR outputs to the power amp
    • Balanced cables = quiet hot swap, no need to power off amplifier
    • This swap is about as fast as before
  • Several of the above tracks played again, plus:
  • Tabula Rasa; Fleck, Bhatt, Chen; 88/24
  • Bourbon & Rosewater; Meyer, Bhatt; 88/24
  • The Oppo’s balanced output is a slight improvement; a bit of the veil is lifted, the bass tightens up a smidge and it’s dynamically punchier.
  • Some of the differences I was hearing were limitations of the Oppo’s unbalanced line out.
    • As mentioned earlier, the Oppo’s primary signal path is internally balanced; the unbalanced inputs and outputs have an additional conversion
  • The Soul still sounds slightly different from the Oppo; it’s more pure and tight where the Oppo gives the impression of breadth & depth.
  • But much like the headphone observations above, the Oppo’s balanced output shrinks these differences.
  • NOTE: from this point forward, all speaker comparisons were done in this way using exclusively balanced outputs from both devices.

Wed 12/26; LCD-2 with EQ

  • Now that I know what the Soul & Oppo sound like, how they’re different, it’s time to listen for enjoyment across a variety of music and see which I want to live with.
  • Listened to the first 2 albums of the Steven Wilson Yes remix
    • Not exactly audiophile material, the original recordings are limited and flawed.
    • But it sounds way better than the originals, which I could never listen to because they gave me a headache.
    • This good music deserved a better recording, and now it has one.
  • Used the Soul’s first notch of crossfeed to fix some of the absolute hard L-R separation. Very nice, a subtle effect that doesn’t eliminate it but makes it less annoying.
  • NOTE: this crossfeed seems more transparent than the one on my Jazz amp. It does the same thing, but with less impact to tone and resolution.

Next, subjective listening notes part 6 (day 5)