Getting into Stax gets you into equipment that can last you, with care, probably close to 1/5 to 1/4 of your total lifespan on Earth.
A really good investment, in other words.
OK, here's what I think:
- Cans
The Lambda Pro headphones are a bit "mellower" and a touch more "balanced" than the SR-303/SR-404's. The newer 303/404's are more technically adept, with a (very) slightly greater operating range while the L-Pros might not be as "adept" they just might be a touch more "balanced".
Either way Stax electrostats are a somewhat acquired taste. They are drier than pretty much any dynamic with a forward midrange, a very extended high end, and a tightly controlled, deep but somewhat dry bottom. If you are looking for midbass bloom to get that "rock sound" - you're in the wrong place. If you want an
extremely extended but yet not "emphasized" bottom end with a highly detailed midrange Stax is that sound.
The 404's have a touch more top end extension but trade away a touch of lower-high frequency "sweetness", IMHO. This can be changed with amp & cable selection if / once you get accustomed to that Stax character.
- Amps
The classic SRM-1 MkII is a somewhat forward sounding amp with a very good, but not "ultimate", bottom end extension. It was a small touch grainy and bright in the upper registers and therefore made a very good match with the L-P's, as the L-P's (in comparison to newer Stax can generations) masked that just a touch, leading to a nice balance (as far as Stax is concerned).
However when matched to the newer generation cans with the thinner diaphragms - Novas and 303/404's - that touch of added "glassiness" on top of the SRM-1's touch of grain combined to make things a bit too much for some people.
All this of course depends upon your source; if you have a very warm source this is not an issue. If your source is dry to begin with 404's + SRM-1 MkII for many people = way too dry.
Stax are easily good enough to show these source differences yet don't worry - most decent sources are good enough to show a Stax system off. It will simply show you all the good...and that bad that you've been used to having masked naturally for you. The good is still there, but you'll get more of that bad. It's not world ending, just telling you even more than you thought you knew.
The newer solid-state amps are somewhat "rounder" in the top end response, versus the SRM-1, to rebalance the can/amp combo back more towards the SRM-1/L-P combo. So while you can easily use a pair of new cans with a SRM-1 classic amp the cans will probably work best, for most people, with an amp of approximately the same generation.
Those amp clauses can be thrown out the door if you use one of Stax's classic "upgrade" amps instead of an SRM-1. Those optional "upgrade" amps, like the T-1, T-2 and SRM-14S (my amp), went for a higher performance than the SRM-1 to begin with and still do a decent job with the new generation cans.
If you like the Stax sound but wish for a bit of "bloom" in midrange, instead of the classic Stax SS "dry" sound (OK, it's all relative), try the tube amps. You can alter the sound of the tube amps by rolling tubes - changing tube sets. The Stax tube amps bring classic tube traits to the Stax cans and can be a bit of a bridge to give Stax cans a touch more warmth and roundness. Remember that the Stax sound is intrinsic so we are talking modest differences here - a SRM-006 or 007 will not make a pair of 404's sound like Senn 650's
- Extras
Stax are high enough resolution devices that they can easily show the differences of many components in your audio chain. If you have never thought you could hear the difference in a pair of interconnects - because (comparatively) your system did not have the resolution - you certainly will when you step up to your new (or "new") Stax system.
Again, that is not a world ending deal breaker. You are simply hearing everything, instead of only part, of what is going on.
I probably would not recommend any silver interconnects, stick to copper or maybe try a copper/silver blend. There are "dark" IC's and "bright" IC - you can tailor your system's nuances with these IC's (once you accustom yourself to the Stax sound).
I, personally, really do not hear much of a difference between power cords but, then again, my SRM-14S has a huge (comparatively) external power supply and could be masking this issue. You may wish to try a cord, prices vary greatly.
If you sit more than 4 feet away from the amp while listening a Stax extension cord is one of the best investments in convenience you will ever make.