Interesting you mention Nelson Pass, surely one of the greatest designers in the audio world. He seems to really like the LSA design, at least based on his comments on the DIY thread. Would be nice to have a First Watt Lightspeed/B1, with the ability to toggle between straight and buffered (when needed), along with multiple inputs (3?) and possibly XLR - that could be a real winner assuming no need for gain. Though it would likely be $1500 or so for nice casing. I would buy that in a minute. Still, even then, it would not make other preamps obsolete for many different reasons.
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.
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.
- ...
- 1866 posts total
Considering Nelson has freely participated and contributed schematics on the Lightspeed thread over on DIYAudio, I'd have to say he must feel this is a pretty good design and it certainly got his attention (as it has other designers of note). Problem with most Pass/First Watt amps is they are not ideally suited to passive designs due to their low input impedance (this is obviously why Nelson designed the First Watt B1 buffer and Pass Labs markets an active line of preamps). Here's a good read from Nelson: http://firstwatt.com/articles.html Click on the B1 Buffer Preamp link. Seems Nelson reiterates a few things we've been saying around here about ideal conditions (impedance matching) and offers his method and design to avoid that. Here's an excerpt: So here we are in the New Millennium, and thanks to Tom Holman and THX we’ve got lots of gain in our electronics. More gain than some of us need or want. At least 10 db more. I especially like the use of the terms "just musical perfection", "really - I'm being serious here", and "reacting psychologically" in the article to emphasize some very interesting points (and all of this of course coming from a genius). |
Seems to be heating up again. Teajay, you're bold to try and speak for some middle ground on this thread. Many that post here are very reasoned and good folks. Like you have said in several of your recent posts, the issue is not with most of the seasoned, good-hearted posters here, but rather the builder of the LSA. On more than one occasion he has said active designers and those that prefer actives, do so for one of these (less than righteous) reasons. Yes, I am paraphrasing a tad, but spot on in intention. - have a tin ear - like distortion - in it for the money only - charging tooooo much - LSA is absolutely THE standard Fact is many Aphiles like actives because well executed ones sound more like music to us. No, we are not tin eared or crooks. No, we do not like distortion. Yes, we like natural sounding music. Fact is, many roads lead to this musical end! Absolute statements by the builder are absolutely out of bounds here. He can argue his point if he like, but stay away from absolutes! The rest of us are free to use absolutes - to our own peril :-) Not the builder. Just my opinion. |
"...fact is, many roads lead to this musical end!" Very true - there will always be a place and purpose for well designed active line stages, and I have no doubt that there will be systems in which they sound much better than any passive might, for a variety of reasons. Having found the LSA through the DIY thread, the one thing that never seemed to be the case was that George was primarily interested in making much money on this, or really making a business of it. Sounded to me like if he could pull it off, he would rather license his patent to other folks who might too think it is a good idea, collect some royalties, and spend some time surfing. And he seems to be a true believer in his approach - rightly or wrongly - which as you suggest, doesn't mean it is the only approach to musical satisfaction. |
- 1866 posts total