2 very basic and unrelated questions:
1) in stock configuration, does the bar/spring on the 007 face the front or back? I got mine second hand, and while I don't think the previous owner made any adjustments, I just want to check.
The first 007 Mk1 I tried was owned by a Stax dealer (first-hand), with no mods at all, and the bar pointed to the front. I think it's the same with the 009. The placement is likely not as much for sonic reasons, but for comfort: my ear touches the bar if it's pointing to the back (even when it's pointing down or up).
2) Do you find the 009 to be brighter, less bright, or just as bright as the 507? Ive heard a few different opinions, but not enough to get an idea of what the consensus is. I've also never been fortunate enough to hear the 009, so this would provide a nice point of reference.
They are different kinds of brightness: the 507 is lower in frequency and a more narrow distribution. People who find the 507 etched (I don't), are usually still fine with the 009.
They sound similarly open, the 009 being the more balanced/neutral and more open sound, with better.. everything. Yes it is perhaps with more high frequency energy, but rather evenly spread out, is not disturbing me at least. Also the more and better bass and more transparent midrange, with bigger sound stage puts the treble energy in a good context. I am not sure if I can really quantify the differences, but it's similar "house sound", and a departure from the 007.
In general, I prefer the natural neutral sound of the 009 over the darker, warmer and more euphonic 007 Mk1, but the treble of the 009 is indeed a bit high when compared to the 007 Mk1, so the latter may be preferred with some types of music. The treble of the 007 is definitely enough for me, just right. However, the 009 is better in many ways whereas the 007 is better only in some ways and some music... so if there has to be one headphone, the 009 is the best - pair it with the right amp.
You have to listen to the 009, really. You need to make your own choice for your own ears/auditory cortex and wallet. If you like it, get the money and buy it... you won't regret. However, when you want to compare it to the 007 Mk1, more time is needed, since the 009 makes a better first impression, but the 007 Mk1 may win you over with time. As described earlier, it is possible to tune the 007 to sound less warm and more neutral, by rotating the bar downwards (and doing the foam mod), but AFAIK there are less or no possibility to make the 009 sound more warm, except perhaps more stuffing to the back half of the earpads, and amp/tubes choice. So in the end the 007 Mk1 may just fit the bill better. I could live with either - but when a choice is given, life is hard
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