See what I mean? So, I made my bid, managed to get them for 12 Euro (17 US$, really!), and eagerly awaited their arrival. This is what I got:
Side of the box, this picture:
with the following text:
N6330 dynamic HiFi Stereo headphone
Frequency Range: 16-20,000 Hertz
Nominal Impedance: 2 x 600 Ohm
Sensitivity: 94 dB SPL at 1 mW
Max. power input: 200 mW DIN
This picture I took of the name plate before I had to remove it in order to open the cans and remove the foam:
And the cans themselves:
Before I start my review of how they sound, and compare them with both the Sextett and the K340, my “reference” cans, some additional information:
Before I made my bid I tried to find out about these cans on the web, but only managed to locate two references. One was a listing of a Dutch Hifi museum, with a picture of the cans, the other a post on a Dutch Hifi Forum by an owner, who mentions that he had compared them with many other headphones, but still preferred the N6330. This statement, combined with the fact that I could ascertain from the box that they at least were built the same way as the Sextett, with the 6 passive drivers, gave me a good indication of its potential quality.
After receiving them, seeing the orange disks and the fact that they were made in Austria, confirmed the AKG connection. The pads are the exact same size as the Sextett, and the cable is the same as the one on the K340. As I hadn’t known about the Philips/AKG connection, I continued my research and managed to find out that in the seventies some high quality microphones were manufactured that actually bear the name AKG/Philips, and that at the end of the seventies Philips Austria was the majority shareholder of AKG.
I haven’t been able to figure out who actually manufactured these cans and in which plant, but it’s safe to say that AKG must have had a big hand in the process.
So, how do they sound?
To compare phones or equipment I use a set of tracks that are a mixture of folk, classic, pop and rock. I know this music very well, so it’s easy to notice new aspects, or the lack thereof. The first time I hooked up the Philips I used my old amp, a DIY-made OTL NOS-rolled tube amp based on a design by one Dr. Friedli using two Sylvania 5814A (12AU7/ECC82) tubes, the next step up for me from the portable Headstage Lyrix. This amp is not bad at all, but compared to the amps I currently use, it does sound somewhat “edgy” and “sharp”. That explains what happened when I first listened to the Philips. At that time I alternated between the K340 and the Sextett, depending on the music and my mood, as I still do now.
With the ECC82 amp both cans tended to sibilance, so the first thing I noticed with the Philips was the lack of that. Both AKG phones sounded slightly unbalanced with that amp, and with the Philips the balance was restored. The high frequencies were just right, maybe slightly laid back, but still very realistic and natural.
The mids were even better than both AKG’s. It’s hard to describe as both AKG’s absolutely excel in that, each in their own unique way. The best way to put it is that it sort of combines the sound of both AKG’s into a very coherent and solid presentation.
The bass was at that time way too overbearing and muddy, although this still didn’t prevent the N6330 from becoming my favourite for as long as I used the ECC82 amp. It then also occurred to me to open it up and see what I could do to improve bass response, something I had not wanted to do, because it would mean flipping out the name plate and possibly scratching it.
Of course, as you can see from the picture I took after my attempts at opening it, it did get scratched (stupid! ), but anyway, I removed the foam layer, which hadn’t started to really crumble by the way, in the hope of slightly lowering the level of bass. And indeed this did the trick. Bass response was now more in balance with the rest of the spectrum.
Around that time, two new eBay acquisitions arrived, and I have been busy testing these, neglecting the N6330. They were a Xiang Sheng 708B tube amp, which I immediately rolled with some military grade Russian tubes before burn-in, and a hand-made discrete build of a design by Helmut Becker, called the RKV Mk I, the predecessor of the renowned Audiovalve amp. Now, I am not yet in a position to say which of these two amps is better, because I really like them both and this would be off-topic, but both of them are definitely better than the ECC82 amp, and this fact changed the perception on the quality of the cans in my possession.
Both AKG’s lost their “sharpness” and became even more amazing than I had experienced them before, and unfortunately for the Philips, the reverse applied to the N6330.
The mids are still very good, and on a par with the AKG’s. It’s hard for me to say which of the three I like best in this respect. The differences are quite subtle, and it really depends on the music.
The highs are now a bit too laid back and in the background. In this respect the Sextett is sparkling, alive and present, the K340 is silky smooth, accurate and natural, while the Philips is… how to say this, in Holland we have an expression that says, it’s neither fish nor meat, meaning that it’s nothing special, that it can’t seem to decide what it’s going to be.
As for the bass: I experience the Sextett as well defined and textured, the most accurate and clean of the three, but not going as low, and/or cut off sooner. The K340 is warmer, goes slightly deeper, but is less nimble and has less punch. The N6330 on the other hand is less accurate than both AKG’s, but goes quite a bit deeper, although I get the feeling that the really low frequencies are a bit too loud. This makes a bass drum a bit too overbearing on some tracks, but makes the sound more realistic on others.
A very important factor for me personally is that the sound stage is less deep, wide and coherent compared to both AKG’s.
As I’m still burning in and playing around with my two new amps, I’ll continue to evaluate the N6330 as well.
I am wondering if it might be worthwhile to put back the foam discs?
And would it be sacrilegious to equalize these cans in the digital domain, higher the highs and lower the lows, so to speak, to rebalance them?
Well, that’s all for now. Please note that just before I was going to post this, I noticed THIS thread and realised it concerns the same headphones. Rather than posting there, I decided to start a new thread, mainly because now the title includes “N6330”, so others will be able to find it.