Lightspeed Attenuator - Best Preamp Ever?


The question is a bit rhetorical. No preamp is the best ever, and much depends on system context. I am starting this thread beacuase there is a lot of info on this preamp in a Music First Audio Passive...thread, an Slagle AVC Modules...thread and wanted to be sure that information on this amazing product did not get lost in those threads.

I suspect that many folks may give this preamp a try at $450, direct from Australia, so I thought it would be good for current owners and future owners to have a place to describe their experience with this preamp.

It is a passive preamp that uses light LEDs, rather than mechanical contacts, to alter resistance and thereby attenuation of the source signal. It has been extremely hot in the DIY community, since the maker of this preamp provided gernerously provided information on how to make one. The trick is that while there are few parts, getting it done right, the matching of the parts is time consuming and tricky, and to boot, most of use would solder our fingers together if we tried. At $450, don't bother. It is cased in a small chassis that is fully shielded alloy, it gets it's RF sink earth via the interconnects. Vibration doesn't come into it as there is nothing to get vibrated as it's passive, even the active led's are immune as they are gas element, no filaments. The feet I attach are soft silicon/sorbethane compound anyway just in case.

This is not audio jewelry with bling, but solidly made and there is little room (if any) for audionervosa or tweaking.

So is this the best preamp ever? It might be if you have a single source (though you could use a switch box), your source is 2v or higher, your IC from pre-amp to amp is less than 2m to keep capaitance low, your amp is 5kohm input or higher (most any tube amp), and your amp is relatively sensitive (1v input sensitivity or lower v would be just right). In other words, within a passive friendly system (you do have to give this some thought), this is the finest passive preamp I have ever heard, and I have has many ranging form resistor-based to TVCs and AVCs.

In my system, with my equipment, I think it is the best I have heard passive or active, but I lean towards prefering preamp neutrality and transparency, without loosing musicality, dynamics, or the handling of low bass and highs.

If you own one, what are your impressions versus anything you have heard?

Is it the best ever? I suspect for some it may be, and to say that for a $450 product makes it stupidgood.
pubul57
http://wajonaudio.webs.com/GET%20THE%20PERFORMANCE%20of%20a%20$20k%20PRE-AMP%20for%20$200.html
Not going through, don't know why. Google warpspeed attenuator you should find wajonaudio a few links down.
I for one would love to see this thread die already. I've followed it on and off from the sidelines for the last 15 months and for the most part it's little more than a three way conversation among like minded audiophiles... At one point I even suggested to George that he start his own forum, but as he said it would distract him from surfing. cool.

Here's my take, if anyone cares. Even if the LSA is the best, I'll never buy it. It's just to restricting in the real word. I need the flexibility offered by full function preamps, both tube and passives.

I've lived for years with a John Chapman, Bent Audio NOH. It's a passive similar to the Music First and based on the same S&B transformers. (Mine are copper.). It has 4 sets of RCA inputs and 2 xlr inputs, it outputs 2 sets of either single ended or balanced feeds, sports 6db of gain, has flooring grounds, etc.... I run 20 foot interconnects to mono blocks and a sub. Short interconnects and one input - no way.

I've also lived with a great dual mono tube preamp that offers similar flexibility.

I guess since this tread won't go away I will.