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
You must order directly from the maker in Australia. A google search will help you find him. I get the feeling he is an individual making a few of these and he pursued this without the idea of starting a real business, but word-of-mouth has proabably driven more business than he expected, so I have no idea how long it takes form him to make and deliver, especially after Sam Telligs review which essentially reached the entire North American audiophile community. He does have a minimalist website.
Hi fellow audiophiles, first off let me thank you Paul for starting up a Lightspeed Attenuator thread as writings about it were so scattered amongst the other non descript threads, it would have looked sus if I had started it.
I have a simple website at www.lightspeedattenuator.com and you can also access it via the Audiogon manufacturers listings.
If any of you would like a PDF sales/pricing/shipping brochure you can pm me via this forum with your email address and I will send it to you.

Cheers George
I love my Lightspeed, but it is not in my system for one simple reason. My Supratek Chardonnay is equal to the Lightspeed in all regards; transparency, slam, finesse, soundstage, etc., but my Chardonnay is not stock. It has a DACT attenuator and VCaps, both of which added much greater transparency. I also use WE 350B's that take the Chardonnay to another level, IMHO.

The only thing the Lightspeed can't do that my Supratek can is to add the 3 dimensionality and warmth of tubes. That speaks volumes considering the Lightspeed costs only 500 bucks. But regardless of price, the Lightspeed is phenomenal.
There is another LDR preamp on the market called Lighter Note Preamp but it's DIY mostly but costs I think around $170 for the kit. But you can get the PCB populated by the designer for a little more. All you have to do is get the chassis, RCA, and knob and put it together. I think a fully built unit is in the future but don't know the cost. I heard this at the Lone Star Audio Fest and was surprised by it's sound. I've had passives in the past based on DACT and Alps pot which were detailed but thin sounding, but the LDR was surprisingly full and smooth and detailed at the same time-sounded like the best of tubes without the draw backs. Any way I have a Bent Tap X on it's way and will also get and LDR preamp to compare for myself.