Tachikoma

I'm just going to say that if you have the chance to see the Expanse disassembled, you'll know what I mean. I agree it sounds way overdamped but the damping itself isn't the whole issue

I'm a bit late, but just saw this - educated guess is that the passive components and the wave guide inside are probably a big part of this whole "tuning the waveform" thing that makes Expanse + Stealth sound much more like live music vs "a headphone".

However, in the process of putting all these things in, yes, it dampened the sound. Tradeoffs.

Granted, this is only based on a few brief listens, a brief glance (of a privately owned pair, NOT ripping apart a pair at a demo / public event) where I may have missed a few things, and the videos DCA made with HF (I think) where they talk about the wave guide and managing long wave forms for bass vs short wave forms for treble, etc.

Curious what everyone else thinks too.

what dac is it?

Are you using high impedance headphones?

Singxer sda-2 (10 ohm output impedance), and I’m using phones ranging from 32 ohms to 300 ohms. The iFi Gryphon (100 ohm output impedance) is also good with 300 ohm headphones and IEMs.

All dynamics (hd650, ms-pro, es-r10, aliexpress r10 clone) of course, no planars.

Preamp into what exactly?

Another tube amp (3-stage 45 PP). It has its own volume pots (highly inconvenient dual mono "stepped" pots), and for whatever reason, it did not like having the Sys in front of it either. Then again, neither did the Magni 1.

Ok, I have definitely exaggerated the differences. However, I still detect a decrease in bass definition and softened treble from the preouts (but not with a very high level of certainty... and I'm tired of AB-ing). Would be nice to have more data points.

I'm following @atomicbob's SOP of passive attenuator and amp pot set at unity gain. Does this count as 2 pots in series? Maybe it's anti-synergy of the source and pot impedances.

@crenca significant loss of detail and immediacy. Having a Sys between the parasound dac2000 and magni/45 tube amp significantly worsened their sound. I first noticed this with the Magni, actually.

Although cable length is a possible confounder, the setup with Sys had 1 m cables, while the setup without has a 2 m cable.

@gixxerwimp Yeah, its possible that lower impedance sources won't be quite as badly affected. The Theta Gen VA (which happens to be available locally...) with its 1 ohm output impedance probably wouldn't care as much.

The setup you described is exactly how I had previously configured my own setup. The dual mono pots on my amp are such a pain in the ass to use.

Just checked out the Taobao listing, they're basically offering copies of the HE-R10P for $400 https://item.taobao.com/item.htm?spm=a230r.1.14.43.7f5b7d3dABRZNy&id=637295584936&ns=1&abbucket=4#detail

... the need for more open loop LF may have been alleviated by swapping in a pair of Shuguang CV-181Z from my stash. Still rolls at 20 Hz without feedback but wtf is this bass. Anyway, the answer to my question seems to be "nope", much too close to the max rating.

Yes, I was eagerly waiting Kerry's take on the CFA3. I hope they survive.

and the portable electrostatic amp...

I was checking periodically. It's working again.

Also, the MS-Pro scales surprisingly well with amping. Wasn't sure it was a keeper until I had done this.