RudiStor NX-03, RPX-33 [NX03, RPX33]: Rudi rules!

[Y5220]

Dear Dr. Rudi Stor,

Please, have mercy! I’ll explain.

Yesterday, I received the NX-03 amp that I bought from you. The amp arrived safely and was, indeed, very carefully packaged, as you promised it would be. I then started putting it through its paces. I got the burn-in process started with the Sennheiser HD650, a relatively heavy load. Right out of the box, using the DAC in the Grace m902 as source, I noticed how the NX-03 grabbed the HD650 by the throat, so to speak, with an iron fist. There were loads of power on tap, and I breathed a long sigh of relief. The black background you described on your website was there too. At this point, just minutes into one of my favorite jazz organ recordings, I thought to myself: “This amp is promising!”

Then, I left, to teach my evening classes.

When I came back, late in the evening, I turned the amp on again. The HD650 was still the headphone of choice for a few more minutes of burn-in. This time, I thought I’d throw a marvelously dynamic soundtrack at the NX-03 – an episode of the TV series “The Unit” (a real sonic experience, as far as these things go). This was supposed to go on for some 15 minutes, since it was bedtime for me already. I watched the whole episode. I remember thinking: “The HD650 has never sounded better.” Then I couldn’t resist extending the audition just a little. Since it was bedtime and music gets me too excited, I thought I’d just try a little Rolling Stones – relatively light fare, fairly easy to turn off. I started watching disc three of “The Biggest Bang” DVD set. The first two tracks – a great recording of the RS in Japan – came and went. When I noticed it, I was already deeply into the China performances. I thought: “This amp is really very promising.”

But then I made my fatal mistake: I pulled my favorite Albert Collins DVD – “Live From Austin, Texas”, from the “Austin City Limits” collection – and thought: “I really shouldn’t go to sleep before I see how the NX-03 performs when mated with my #2 favorite, the Denon D5000 – just for ten minutes.” My jaw dropped! The amp had sucked me deeply into the recording. Everything I’ve long associated with the cost-no-object hi-end audio experience was there: dynamics, extension, airiness, timbral accuracy, a deep and wide soundstage, and that gargantuan, pitch-black background when the music stopped. Long story short, at about 4 a.m., the thought that I’d really prefer to make sense in my classes the following day finally put an end to the listening session.

You can well imagine what would have happened if I had reached for my headphone reference, the mighty JVC DX1000, can’t you? Yeah, I’m proud I resisted that temptation last night and managed to make some kinda sense in class today. [Note to self: Be careful around this little RudiStor monster tonight!]

So, how do I rate my out-of-box NX-03 experience last night? Suffice it to say that, 24 hours after receiving my first RudiStor amp, I placed an order for the second one, the dual-mono solid-state extravaganza that goes by the name “RPX-33-EV08”!!!

You see what you’ve got me into, Dr. Stor? Now I need both a second job to pay for the bigger amp and a vacation to enjoy them both. And I sense a little conflict there.

I feel so strongly about this that I felt duty-bound to warn my fellow Head-Fi’ers against the perils of exposure to your products.

Sincerely,
Soundinista

PS: Thank you!

EDIT: My RPX-33 content begins at #61 below. Comments by others throughout.

 

[Audio-Omega]

Get one soon and tell us what you think. I'm sure RPX-33 is a fine amp.

 

[onocentaur]

^ x2. I'm really interested in the RPX-33 and would love to hear your thoughts.

 

[Y5220]

Thank you, Audio-Omega, Onocentaur! Yes, the RPX-33 will be here in a few days. Will report back.

Here's my astonishing discovery of the second night with the NX-03: It transformed my DT990, 600 ohms! I don't mean a little better; I mean much, much better!

This is quite a shock to me. I've had these phones for a year now. I've been unfair to them in what I wrote at the DX1000 thread when I called them very dark. Now I see that my other amps were not driving these ultra-demanding phones properly. I've rediscovered these phones. Last night, I had the distinct impression that the DT990-600 are much more fun than the HD650. The bass, in particular, sounds so much better now. The fantastic bass slam that I knew from my old DT990-250 is here now.

Folks, I may be wrong, I may be naive, I may be ignorant, etc. But there's one thing I'm confident I'm not: a fanboy. (All due respect to fanboys everywhere; I say this with love.) I don't know this Dr. Rudi. I owe him nothing. I'm not a dealer, not a manufacturer, not a professional hype merchant in disguise. I hate snake oil peddlers. I have no intention to sell anything at Head-Fi. Never have; probably never will. I'm just a headphone enthusiast, with some twenty years' experience in chasing the hi-end holy grail. I'm not saying that Rudi Stor is it. What I'm saying is that I just never had this kind of headphone experience before. And I do have fairly good reason to believe I've been cursed with a good pair of ears. That's all.

 

[blessingx]

Congrats Soundinista. I haven't heard the NX03, but reviewed a NX01 a few years back and just received a new NX02 on clearance on Wednesday (from company that went out of biz for $400!). It really does wonders with the HD580 and W1000. In my case it's for a secondary system, but a secondary system I suspect that's going to get a lot more ear-time than I was expecting. Really quite engaging, very nice soundstage and surprising clarity. I may be on a honeymooon myself, but quite a beautiful presentation. If memory can be trusted there was a decent bump from the NX01 to NX02. May be the same between the NX02 and NX03.

So are you going to keep both amps?

 

[markl]

RPX-33 is a monster, in the best possible sense. Great tonality and body, high resolution, with jet black background and oustanding dynamics. Can't think of anything it does that I don't like. Congrats Soundinista, I'm sure you'll love it! (but be careful or you'll end up like me with an RP010B

)

 

[SleepyOne]

Agreed, that is the problem...........RPX-100 is constantly crossing my mind lol!

 

[nc8000]

Quote:

Originally Posted by SleepyOne /img/forum/go_quote.gif Agreed, that is the problem...........RPX-100 is constantly crossing my mind lol!

Then you must go get one, it really is fantastic, however I don't know how it compares to the other amps in his lineup as I have never heard any of them. RP010B however is totally out of my reach.

 

[Y5220]

Quote:

Originally Posted by markl /img/forum/go_quote.gif RPX-33 is a monster, in the best possible sense. Great tonality and body, high resolution, with jet black background and oustanding dynamics. Can't think of anything it does that I don't like. Congrats Soundinista, I'm sure you'll love it! (but be careful or you'll end up like me with an RP010B )

Yes, Mark, I hear you! There's gotta be some serious magic going on in Trieste, Italy, when a guy sells two fancy amps in 24 hours to an old skeptic, an old cheapskate like me!

I'm now trying to forget that you have an RP010B!

I've just used the term "fancy" to describe Rudi's "entry-level" NX-03. Yes, fancy -- a very fancy-sounding wolf in sheep's clothing!

Blessingx, yes, I'll be keeping both amps. (Should have been clearer about this in the post.) Can't let go of the NX-03 after what I've heard. But this is a first for me: I just had to see what Rudi can do with a bigger budget (though I certainly know about the law of diminishing returns).

Cheers,

 

[stvn758]

Their balanced Amp looks nice. How do these compare to Headroom Amps, all the VAT and import duties are putting me off getting one of theirs, these also seem to be made in Europe.

 

[thathertz]

Oh God.....just when I thought I'd be settled with my system for
at least 6 months...you start talking about the RPX-33!!!

I was one of the lucky two (with Blessingx) that got the deal of the
century on the NX-02 from Utrasone USA. Haven't had much time
to listen but with Edition 9's, straight out of the box, the NX-02
was a real surprise. Huge soundstage with superb depth, outstanding
bass response and massive detail. I instantly understood what people
meant when they say 'airiness'......ahhhhh so THAT's airiness.

I'm sure that the Edition 9's play a big role in this. Since the NX-02
was tweaked with the Proline 2500's in mind it just had to have synergy
with the Ed 9's but I was not expecting so many jaw-dropping moments.

I'm planning an extended listening session this evening for the first time
since I received the NX-02 earlier this week.

Got some new SACD's, a really nice bottle of Merlot, vintage cheddar
cheese and some 'reggae reggae' sauce. Good to go.

This is what it's all about

 

[SleepyOne]

stvn758, yes, I think most of his amp is made in Europe (not sure re: nx-03, need to ask Soundinista) so no VAT, nice!! That was one of the main reason I chose rudi over eddie current and woo (however I still want one of those in the future!)

Definately will be interesting to find out how rpx33 ev08 vs nx-03 vs headroom desktop! Can't wait for Soundinista's review!!

Note rpx33 ev08 does take 2 weeks or so to run in, and you may need to experiment plugging one way or the other with the 2 pin power cable supplied to get the best sound - i.e. plugging it one way maybe better than the other way. Alternatively you could just use a UK or US plug cable.)

Lastly, unfortunately you don't have the AKG 701 any more, but I can say that I am getting very deep and dynamic bass from it using the rpx33.

 

[Sovkiller]

Welcome to the family, and enjoy it, just sit now and get sucked into the musical bliss...

 

[Y5220]

Thank you all!

Quote:

Originally Posted by thathertz /img/forum/go_quote.gif Oh God.....just when I thought I'd be settled with my system for at least 6 months...you start talking about the RPX-33!!!

Trust me, Thathertz, I know exactly what you mean! Picture this: a generally level-headed Head-Fi'er who's always been relatively good at keeping his audiophile urges in check, a guy who's used to planning for these purchases months in advance, gets a package from Trieste at 3pm, puts the amp to work at midnight, and decides, only four hours later, that he likes the devilish machine so much that he will not be able to resist getting another black box from that same Italian city!...

Unprecedented in my household. Thought I owed my Head-Fi buddies a report on such alarming events.

Let us know about that NX-02 experience.

 

[thathertz]

Quote:

Originally Posted by Soundinista /img/forum/go_quote.gif Thank you all! Trust me, Thathertz, I know exactly what you mean! Picture this: a generally level-headed Head-Fi'er who's always been relatively good at keeping his audiophile urges in check, a guy who's used to planning for these purchases months in advance, gets a package from Trieste at 3pm, puts the amp to work at midnight, and decides, only four hours later, that he likes the devilish machine so much that he will not be able to resist getting another black box from that same Italian city!... Unprecedented in my household. Thought I owed my Head-Fi buddies a report on such alarming events. Let us know about that NX-02 experience.

Will do Soundinista

We're all addicted.

I thought i was on the home straight to sobriety.

And I would have gotten away with it if it wasn't for you pesky HEAD-FIERS!!!! . * (scooby doo)

Have a good night all.