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treuben

VAF I-91 driver issues

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Hey all! I have just borrowed a set of VAF I-91 speakers (I am assuming mk2 models as they have the sculpted smaller front baffle arrangement though no plastic plugs for the grills - *edit* I assumed wrongly!) from a friend who is the original purchaser with a view to buying them from him (he has some other hi-fi projects happening and not a lot of spare time ATM) but I've noticed, with some lessening of my excitement, that the voice coil former rubs on the pole-piece of one the the Seas coaxial drivers that are used in them and makes a slight buzzing sound like a poorly fretted string on a guitar at times. It appears to be a manufacturing issue (initial cone misalignment) that has either become apparent with sagging (I don't think that's so likely as it's only a 7" driver but those of us that have seen a few years will have seen this with some large coaxials and high efficiency/PA drivers) or loosening of the surround and spider over time (more likely IMO). When compared to the other driver it's apparent that the gap is very uneven with a wider gap on one side of the pole piece to the other - and it's not that generous on these drivers to begin with.

 

Now I've had a lot of speakers and sometimes this misalignment happens without issue - notably I've recently seen some brand new Usher S-520 stand-mounts with pretty poor woofer VC centering that sounded just fine..and I absolutely realise that properly centered voice coils can be toasted by abuse and swell and rub but these lived their listening lives attached to an Almarra EL84 that was converted to triode operation.. so you have a very gentle 3 watts or so being piped to them and no DC happening at all - and I can plainly see 1. the misalignment, 2. the rubbing is happening on the inside of the former and not the outside, and 3. there's a healthy copper color within (by torchlight) and no toasty smell. So, given all this I have some questions!

 

1. Since I can't readily see where to get this particular Seas driver currently (only the clear coned variant which I expect isn't the same) do you think VAF is likely to have replacement units that they would fit under warranty in these kinds of circumstances?
2. Is the ten year warranty on the I-91s dependent upon them being presented by the original owner? He says they're not ten years old and I'm quite happy to faf around in lieu of him doing so getting them repaired due to the nice price he's offering to me to move them on. He mentioned having an invoice in his files somewhere but suggested I just quote the serial numbers and see how I go to begin with so I'll try that to begin with and see how I go. They are numbered 1020 and 1022. (Hmm, upon further inspection they seem to be version "1.1"). 

3. Has anyone else seen this kind of issue with these drivers? I'm a little surprised to see it but also not flabbergasted - it is a pretty small VC gap to begin with so there is always a chance I'd say - I'd say it just scraped through QC without being noisy and only manifest as the driver aged and the surround/spider became more compliant. 

 

I've been looking forward to hearing these for a long time now, and they look like very well made enclosures, so I'm hoping the story will have a happy ending! 

 

I'll post some pics in the next day or two to illustrate.


All the best! 8)

Edited by treuben

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Well, with the rain pelting down in Adelaide and later power failure there was no time for pictures! I called VAF Research and spoke to a delightful receptionist who seemed more distressed than I was at the failure - despite me explaining that it was no fault at all of their company's and that a few high end drivers would be expected to fail regardless of how carefully you were to vet them (I recall some midrange drivers on some Duntech Cown Princes I had where a number of other owners had the fly leads fall off after a few months use - and they were replaced without fuss at the time - if they lasted a year they probably would be good forever and I remember Duntech being quite careful about testing each and every driver in manufacture, in those early days at least - quite possibly VAF are the same. I was lucky and mine never failed). Anyhow, I dropped them off at VAF in the city, where it was very romantically lit (power out, remember!) and a nice gentleman who proved to be the designer (well, perhaps I'm misreporting in hindsight and he was *a* designer - I'm not sure) verified a rubbing voice coil/former by careful manipulation in a few moments. Keep your eyes peeled for a new model largish stand-mount too - it looked great and I don't think it's on the website yet. I'll report on how they go with it all. 

 

Some things I discovered:- They seem to use a similar (the same?) drivers in their current little cube speakers which would make a great set of rears for the I-91s I think. Since I haven't played the I-91s in my own system yet I'm not sure if they're for me but I certainly like the idea of such nicely made coaxial designs being available here. 

The version/mk 2 apparently has slightly raised frequency crossover point for this driver while maintaining flat frequency response - making them perform better at higher (I suspect that means "very high and not how we, or we thought anyone else, would be playing them") levels with respect to distortion profile in the upper registers (always an issue for designers of first order crossovers since driver excursion can be large even outside of the band of the driver, ie outside of where it's crossed over with that kind of filtering) and also improving sound-staging (perhaps because of the same reason - distortion tends to be localised to an individual speakers so these wouldn't be impossible phenomena to link causally, but I'm guessing here). Quality first order crossovers contribute no doubt to the sense of congruence and evenhanded tonal  treatment of acoustic instruments though and that approach certainly seems justified in the overall listening impression - even if I only had a chance to hear them quite quietly. I'm very much looking forward to hearing them properly!

Edited by treuben

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He seems like exactly the kind of guy you'd want in that spot I think. Very knowledgeable and responsive to feedback generally by the sounds. There are certainly people with wonderful technical skills that are not - in fact one might conjecture that that's much more common! I'd rather a Nelson Pass than a John Curl at a BBQ (I think; perhaps that's a premature judgement never having met either) - though I can see that both kinds make their own kind of contribution to the audio world...and neither can be dismissed on those grounds alone.. even if those of us less likely to sketch up a visionary new amplifier topology on the back of a napkin at lunch have our own preferences about with whom we'd like to chat! 

Edited by treuben

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Well, on Aussie rules grand final day (apparently, what do I know!) in Adelaide I had the pleasure of spending some time with a genuinely knowledgeable and passionate man. Over the years I've known a few designers, and, to cut an interesting (to me at any rate) and long story short, I learnt a few things. I have new respect for VAF products after listening to a few of them, and I'd venture, if you've been entertaining thoughts of some compact cube coaxial speakers (there are a few variants these days but the very versatile VAF product most closely matching the brief is the I-90) I'd make sure you didn't drop your cash on anything until you've seriously explored VAF's offerings. As Molly used to say, "Do yourself a favor". What a delightfully delicate touch they have! I don't know what I expected but I was really very enamored with the way, despite being technically tonally flat, they threw a flattering spotlight on the vocals and acoustic instruments, illuminating plenty of detail while remaining entirely musical all the while and, when listening to larger speakers I almost felt I missed that refined, almost elemental experience. There was certainly no misplaced brightness. Classic recordings like Joni Mitchell from the '90s and Paul Simon's Graceland were spectacular, along with the usual demonstration disc quality recordings. I detected no dynamic compression in either design at moderate listening levels in the large listening space and the studio monitor flat tonality made getting into the listening groove a trivial  exercise in brevity. For me at any rate there is a strong case for *both* the I-90 and the I-91 as mains. They have much of the same voice but they both do the critical mids so delicately and adeptly that the smaller I-90 is a *different* joy to its larger sibling. Certainly you could make a fantastically integrated system with both - but for me the I-90s are a unique pleasure on their own. Listening to them made me want _two_ systems. (Computer room/office system anyone?)

Anyhow, I guess I should round out my report by saying that VAF returned the I-91s to fantastic form in short order without charge and surprised me on several different levels. In an industry seemingly composed of equal parts charlatan, snake oil vendors and showmen, these guys manage to make a living making truly technically innovative stuff available at reasonable prices; refining the art - and it IS as much an art as a science - and putting great looking, spouse-friendly and stunning sounding products into the hands of everyday folks (like me) - and backed by a real local warranty service. I've listened to a *lot* of high end hi-fi over the years.. and the great innovators don't always endure for one reason or another. I now count VAF among them, and really do I hope they carry on building their products in South Australia for some time yet. If you're looking for some visually appealing, great sounding boxes backed by sound design and quality Australian workmanship, you'd be remiss in my estimation in leaving them out of your audition process. As a jaded audiophile I'm seldom surprised, and even more seldom pleasantly! I'm pleased to have run across VAF at this late stage of my hi-fi journey. Turns out I don't know everything (don't tell my wife please - I'll never hear the end of it). And who'd have thought it'd be quite so pleasing? 8) Thanks Simon, and thank you VAF. 

 

Edited by treuben

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VAF come through again!

 

This is the 2nd report in the last few months of ,IMHO, VAF going above and beyond in customer service

 

Well done VAF!!

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treuben

 

you should have had a listen to the soundwall as well.  Same speaker driver as the I-91 and I-90.  Your wife might even accept them in a living area in the house!

 

Benje

 

ps as good as the I-90's are (I have a pair, and the precursor icon 195), I think the I-91 are the duck's guts for a stereo bookshelf.

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I agree, with the I-91s being fantastic..and they cover a little more down low than their little brothers I guess, so I'd probably recommend them to anyone that asked for a traditional/cover an acceptable amount of the spectrum for many people type medium stand mounter. Still, there was something special about the I-90s to me, so much so that, for a few minutes listening I felt like they offered something more than simply a subset of what the I-91s could do. I guess that may be a less common reaction (I'm far from a bass head and have lived with bookshelf speakers a lot) or it could simply be that wider bandwidth means a slightly longer period of psychoacoustic alignment - a bit more of a getting-to-know-you  period from my previous system, and that may change with more listening. I certainly like both designs a lot. 8) They're actually reasonably sensitive too - something you didn't always get with the smaller Duntechs I've had. Driving those little monsters with Creek/Cyrus/Meridian etc would have been laughable but I think these VAFs would do very well with such small scale amplification, and they both image fantastically. I mean bookshelf designs often do, but these coaxial bookshelf things are just very, very good in that department.

Edited by treuben

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Simon fixed a small problem with my son's Rega on a long weekend rather than make him wait to send it back interstate under warantee, amazing service. He is a brilliant designer and just a real nice person (so is Phil).

IMO anyone should listen to their new Evo bookshelf before buying any other small speaker.

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