Nest Theater Update On Vinyl Audio Path ~ Tone Control Experiment Failed 07Jun22

As reported in the Compare Tracks entry, going Back To Vinyl has not been up to snuff. I needed to: 1) tame/equalize some of the low-end and 1KHz-2.5KHz shout in the DRC BLHs, and 2) get the subwoofer online in the phono audio path. Enter the Schitt Lokius 6 band analog equalizer ($300, I know - why not the 7 harmonics?). Connection-wise I come out of the Tube Box DS2 phono pre-amp directly into the unbalanced inputs on the Lokius, and from Lokius line out to the subwoofer with one set of outputs and line out to the 300B SET amp with the other set (they are independent and both live). The Lokius is a pretty simple tone control but very quiet to adjust my speakers' frequency responses just a skosh, and the two outputs allow me to bring the sub online. I got it in matte black to match the rest of the NestT gear. A parametric equalizer would've been better but I couldn't find one I really liked as much in the kit as the Schitt as they are mostly rack-mounted pro looking, and often single channel (so I'd need two) and expensive. The Lokius can take its small place in the rack perfectly IMO.

To set the tone control effect properly I measured with full frequency sweeps using REW with everything driven. I used my Topping D10s DAC to get the macOS digital fiber out (carrying the sweep signal) into the analog path just before the Lokius. I narrowed in on the flatter frequency response I sought (my house curve) iteratively. I prefer to attenuate/reduce louder than desired frequencies (rather than boost quiet ones) ~ this scheme better limits introduction of distortions. Results were not encouraging ~ below are the final before/defeated and after/engaged responses using the Lokius. For the NestT the Lokius is set with approximately (each band has +/- 12 dB) 20Hz @ -4dB, 120Hz @ -3dB, 400Hz @ 0dB, 2kHz @ -12dB, 6kHz @ -1dB, 16kHz @ 0dB. I could not get sufficient improvement with the Lokius no matter how much I futzed with it; I don't completely know why the adjustments had as little effect as they did (except at the low end). The Lokius is going back and my pursuit of sonic glory for the phono path continues.

For grins though I also show just the 20-200Hz bass area response to highlight the big improvement made in getting the subwoofer online. I included a view of the high end improvement from the super-tweeters as well, not as pronounced but evident.

Tone control is not a very audiophile thing to do; I guess I just want the best sound from my setup. Some might be lured into constantly adjusting tone controls to account for variances among different pieces of vinyl, not me, it's up to me to get the system/speakers to sound great; it's up to musicians and producers to get the vinyl right. Despite the measured fail, I did a listening test on the tone-adjusted speaker setup sound playing vinyl LPs? Reina del Cid’s Morse Code sounded about the same as pre-Lokius. Meh, but not her fault.

UPDATE 12Jun22 - Watch Your Schiit... I was charged a 15% restocking fee on the $300 Lokius (after a 3 week delay to receive it). This policy was not clear to me upon purchase or in emails sent to me about the purchase. Even as a long term and very good Schiit customer, this happened, and I am pissed.