Anyone have a Music First Preamp ?

Google it. You will likely get the LONG DIY thread on all things LSA. You need to buy direct from George in Australia. Should be <$500 with a Walwart to power the LEDs.

If you can afford the Music First, you can afford to try the <$500 Lightspeed Attenuator - might be interesting if you want to be amazed. When you don't have impedance issues to worry about, it clearly bettered the TVC (S&B) passives I have owned. The low price makes all the more amazing - though it surely cannot compete with the quality of the chassis of MF gear - top notch.

Not that you want to get paranoid about this stuff, the MF is, I am sure wonderful TVC, though I doubt it is any better than the BENT version in TVC or AVC formats, they were and they remain SOTA passives, but if you have <200 ohm sources and 100 kohm input impedance amps, I can guarantee you that the Lightspeed will be a worthwhile listen, and at a much lower price point -- for now.

Yes, the MF is likely to have wider application, and that in and of itself has value.
Having said that, I would be surprised if one would consistently pick it over a
BENT Tap with the S&B, or better yet with the Slagle AVC which I thought was
even better than the TVC version. So for more universal applications the BENT
Tap is the passive of choice for me, but when you have the impedances, cables,
and gain right I have found the Lightspeed to be the best of the bunch - and all
of them are at least very, very good in the right systems. Some times you need
gain, some times you need impedance matching help and these wonderful
preamps might not serve you nearly as well. So no universal claims, but system
context is everything for forming an opinion. I've not yet tried the Magnetic Line
Amplifier by Electra-Fidelity which seems like a very interesting new design with
what would seem to be great transformers that would address most if not all
impedance matches, but like anything in audio, at a cost compared to the
"simplicity" of the Lightspeed. We are indeed lucky to have so many choices.

Dealer of the Year?

It seems that there is shift on the "warmth" - "neutral" spectrum with the various S&B transformers which is why some folks look for a particular version - don't which is which. I did find the Autoformer version of the BENT to be quite excellent - but then I had to go try the LSA:)

I suspect 50kohms would work fine, now if you are looking at 10-20kohm you might be pushing it, though some listeners claim it can also work for them. George from LSA does specify >50kohm - tubes in other words (for the most part. But, that's why Nelson Pass built the B1 - has to drive his SS amps:)

From George in response to the same question in the Lightspeed thread:

Hi Luka, the Lightspeed will happily slot right into most systems, the only thing that is needed for it to give it's 100% performance is that:
1: The output impedance from your source (cdp, dac, phono stage, etc) should be 200ohms or less output impedance and 1v or more output, which most are.
2: The input impedance of your poweramp should be 47k or more, which most are, 47k being the industry standard.
3: The interconnects from the Lightspeed to the poweramp should be 1.5mts or less and of low capacitance (100pf per foot or less) which most good quality IC's are, this measurement is in the cables specs, if not the supplier/manufacturer should know this.

Drubin, it would be good to know about your observations once you have a few weeks under your belt with the LSA - might make sense to post those comments on the "Lightspeed Attenuator: Best Preamp Ever?" thread where those interested would be more likely to find it. Cheers.