IXO ???????????????????

The cost of another 250 was a little daunting though, so I ditched the idea of going active with an IXO and another 250. When I did a tryout of the 135s, they were giving me the sound I was looking for.

Sold off the 250 and got 2 135s.

It's a long way from a 4-pack. But without direct reference to a 4-pack, I don't feel robbed of music anymore. At least in my listening room. Isn't context everything as well?

Perhaps it's happening for you in this way as well? enjoy the music.....

Vik
PS the 250 is not a bad amp. It was really good with Magneplanars and Apogees and Von Schweikerts - but didn't do anything REALLY astounding for the SBLs. I suppose with speakers that go right up the wall "if the room can take it" (thanks JV), you need an amp that can control the driver excursions as well as can be done. Then again some people have had positive results with 140s and 180s and the SBLs - I suppose it's all situational, and what it takes for a person to be happy with what he/she's got

quote:

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Apparently the electronics in the IXO are of a lower grade than the PXO's. That even an old NAXO with a Flatcap was better.

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My experiences with the IXO were nothing but favourable. I have heard the heard the very same pair of Tukans driven the following ways.

1. 180
2. 250
3. 135x2 (also pair of Exposure 16 monoblocks).
4. Pair of 250 passively bi-amping them.
5. Actively bi-amped with IXO and pair of 250
6. Actively bi-amped with Snaxo/Hicap/250x2
7. Actively bi-amped with Snaxo parasitically powered from 52s Supercap.
8. Actively bi-amped with Snaxo and its own dedicated Supercap.
9. Passively amped with 500.

There was an ENORMOUS improvement going from passively driven (by all but the 500) to the IXO with 2x250. The Snaxo 2-4/Hicap was incrementally better, but in the context of the system (CDX/XPS/52/Supercap) not VASTLY better. The Snaxo/Supercap provided the expected gains, but still was not quite the leap that going from 2x250 passively biamped to activating them with an IXO.
The bottleneck of almost all passive crossovers is more like the constriction within a hourglass. Even the finest grain 'sand' will be greatly impeded by the inevitable transit through many metres of inductor coil (and this stuff is no NACA5 either). Phase shifts are horrible especially if the crossover is not first-order. Having experienced the Ixo, I felt it one of the best-value for money products that Naim made, but one that may be overlooked because of its very low price, the need to double up on power amplification and the dogma that a great power amp passively used is better than a lesser on driven actively. True for the 500 vs the rest, but in most systems ACTIVELY driven 250s can effect improvements *in certain crucial and fundamental areas* that are only hinted at when driving the very same speakers passively with 135s. This is not conjecture, this is fact. The added bonus with the IXO is that it allows easy relative tuning between drive units via the rotary pots on the back. Until the gentle reader has heard the effects of activation within a system that is very familiar to them, it is disingenous to empirically dismiss an electronic crossover, even one as unassumingly priced as the IXO. If naim had made the IXO full chassis size, doubled the price and allowed for the addition of an external power supply, these units would be flying off the shelf, even if they had 'only' the same performance.

Ron
Dum spiro audio
Dum audio vivo

http://homepages.go.com/~rontoolsie/index1.html

[This message was edited by Ron Toolsie on MONDAY 11 September 2000 at 13:17.]

Let me try to understand this exactly.... without bring the 500s into the picture, you are saying that the IXO is still equal or broadly equal to an old NAXO/flatcap - and far superior to a PXO - even if the grade of electronics in the PXO may be higher. Because passive x-overs are fundamentally flawed. Is this right?

Sincerely
Vik

PS that old active 250s vs passive 135s debate brings back some memories, man.

quote:

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Yours is one of the most compelling posts I've ever read.
Let me try to understand this exactly.... without bring the 500s into the picture, you are saying that the IXO is still equal or broadly equal to an old NAXO/flatcap - and far superior to a PXO - even if the grade of electronics in the PXO may be higher. Because passive x-overs are fundamentally flawed. Is this right?

---

Not quite Vik... if you have a power amp LESS than a 250, then an upgrade of power amp would probably go further than recapitulating several lesser poweramps. However I have heard a pair of Linn Kabers actively driven with one 250 and 2x180 sound absolutely phenomenal.There is something just so fundamentally 'right' about active systems that is almost unmistakeable once heard, and never forgotten. And a 'humble' IXO is much more of a transparent crossover than far more expensive passive equivalents. The best crossover is NO crossover (electrostats anyone?), but failing that, an electronic x-o is better than about ANY crude passive approximation. Note well some of the speakers that offer great 'gestalt' use a single capacitor as their 'crossover'- which requires exquisitely seamless matching of tweets and mid/bass as there is only a first-order roll-off. For those of you on the brink of activation, do not overlook the IXO as a viable way to do so. Is the Snaxo better??? Of course. But the leap from passive to IXOed active in many instances is greater than between an IXO and a Snaxo. I think that Naim about undermined the street credibility of the IXO by making and pricing it as part of the entry level 'Slimline' series. Bear in mind that IXOs can only be used on 2-way speakers and can only accomodate two stereo amps. Four-packers need not apply.

Ron
Dum spiro audio
Dum audio vivo

http://homepages.go.com/~rontoolsie/index1.html

Agreed Ron "If naim had made the IXO full chassis size, doubled the price and allowed for the addition of an external power supply, these units would be flying off the shelf, even if they had 'only' the same performance. "

Going active with the IXO (after Mana) was the best upgrade I ever made, people seriously underestimate what going active is all about, and also the ixo in terms of an entry level component.

Many Thanks Ron...

naheed...

Having to suffer and endure a (Naim) system mismatch some years before, I was not prepared to make more costly mistakes. Nor did the opportunity to do a home demo avail itself to me.

So, emphatically, "I think too many on this forum just assume rather than demo & comment." is in itself an assumption.

Vik

naheed...

Just ask'n - not heard it.

- GregB
Who has a back-heavy system at present

I feel the ixo did more than say adding a cdx/cds2 (after a few demo's) but it depends what your after, and where you are looking to go really.

For me active just does IT, unlike a single source upgrades can't/don't, active comes across and 'slaps' you round the chops, where as other upgrades just make things more refined.

At the end of the day your system can only resolve from what it gets 'fed' (source), but i think's when your in the middle somewhere its definately an OPTION to consider...

naheed...

It would be good to see active systems (mid-range or low-end) get a revival. One of the nicest systems I ever heard was in 1981 or 82 at the home of the Nytech MD (whose name I now forget) - LP12/Ittok/Asak/Nytech active amps/ARC101s. Very different to passive.

For myself, I had the chance to compare SBLs active with 250s (SNAXO/Hicap) to passive 135s and didn't think it even close--active was WAY better. Also, when I put the question of whether active was worth doing at the 82/Supercap level to NANA, the answer was an unequivocal yes.

The evidence seems clear that different people prefer different flavors of Naim--some prefer passive 135s, some prefer active 250s, some prefer Mana, some prefer Hutter or Base, etc. Far be it from us to try to invalidate a (informed) choice that someone else has made. Given Ron Toolsies report above, it seems clear that very few people have actually taken the time to listen and compare (Frank is specifically excluded from this; his preference for passive 135s must be regarded as the negative impact of Chord ownership).

Cheers,

Bob