Sure, they're arriving next week, so I'll post what I think of them with & without Oratory1990 EQ, but I don't have the old version of the HD600 to compare, so it's not really answering our question of whether the new HD600 is different to the old HD600. I'm flirting with the idea of sending both my AKG K702 and the HD600 (once I've worn in the earpads) to Oratory1990 for testing....he lives in Austria I found out today so postage wouldn't be horrendously expensive. Although I might not bother doing that if the HD600 sounds absolutely fantastic with his current HD600 EQ, but we'll see come next week.
I'm not on there. Did you look over there yet?
Someone over on my thread, on the same topic as yours here, they replied with a couple of posts, saying that Sennheiser central store in Germany as well as another large retailer confirmed that the new late 2019 HD600 is the same as the previous versions apart from just the exterior appearance, the sound is the same: https://www.audiosciencereview.com/...vs-the-old-sennheiser-hd600.14668/post-455940
Well the HD600 arrived with me on Friday, I've listened to them quite a bit now, both with & without EQ. Stock (without EQ) they sound great and they're the best sounding headphone when stock that I've ever heard (which is not too surprising because they're one of the closest matches to the Harman Curve out of any headphone ever made as proven by measurements although matching the Harman Curve is not the only measure of a capable headphone), but really I've only got NAD HP50 and AKG K702 as worthy comparisons that I own. In it's stock form the midrange and vocals are amazing in terms of the feeling of smoothness and detail & natural feel in that area. Overall tone of them when stock is lacking a little bass somewhere below 100Hz, although I wouldn't describe the headphones as bright.
Congrats to you & Solderdude on building a hardware solution for it, and for having the technical know how for how to do that! I'm ok with using software EQ though for my needs, but I'm sure there'd be people that find a hardware solution useful. I see the SeNNator extends the bass flat all the way to 10Hz by adding up to 12dB at 10Hz....do you know how that affects the distortion in that area because that's a big boost and I know from some measurements I've seen that distortion measurements are relatively high in the sub 100Hz area on the HD600. With me using Oratory1990 EQ he boosts the bass there by 5dB and I've not noticed any distortion of bass in listening (not that I'm trained in distortion detection), but you would be more than doubling the amount of energy in that area than even the +5dB boost of Oratory in that area?
With my NAD HP50 (which is flat to around 10Hz) I can hear 19Hz just barely with test tones at normal listening volumes, also Oratory1990 EQ. Well it's good your side-by-side of the largely boosted bass in the HD600 isn't noticeable in your listening tests there in terms of distortion albeit you're pointing out your 30Hz limitation. How do you mean by taking the whole of Oratory's EQ curve into consideration - you mean have I applied a -5dB preamp to allow for the 5dB boost, yes I can see the whole EQ curve in PEACE and Oratory lists the preamp required anyway, but I don't think you're asking me that? (I also run a High Pass Filter at 12Hz just to start taking out the boost from 20Hz because that's the point at which I don't hear anymore from my NAD HP50 test tone experiments......High Pass Filter maybe in a bid to help clarity in the rest of the range, seems to work in that regard on the HP50).
I get SeNNator's bass elevation as rather moderate.
I agree with your SeNNator evalutation of the amount of boost at different Hz you listed, but your Oratory ones are wrong, it's here on the total EQ curve (https://www.dropbox.com/s/dm0m6u3s3b4zqzl/Sennheiser HD600.pdf?dl=0 ). 20Hz 4.5dB, 30Hz 4 dB, 40Hz 3.5dB, 50Hz 3dB, and then goes in straight line down to 0dB at 90Hz.....so you're overestimating the Oratory bass boost by 1dB on each of of those - ah yes, just read that you opened the wrong pdf file, that's why you got the figures wrong. The SeNNator starts boosting the bass above Oratory from about just below 30Hz down to 0Hz, but Oratory has slightly higher bass boost from 30Hz to 90Hz, because the SeNNator doesn't start boosting the bass until 50Hz and below. If "massive" boosting of the bass below around 22Hz (by the SeNNator) doesn't have detrimental effects on the ability of the headphone to render the rest of the frequency range clearly then I guess it doesn't matter, but I don't know if that's the case or not, although my subjective testing of rolling off bass boosts on the NAD HP50 from 20Hz using a High Pass Filter seemed to clear up the clarity of the rest of frequency range when listening (I did that testing a few months ago and since then include the same High Pass Filter on all my headphones).
I agree with your Oratory figures - they are definitely the better ones.
His 650 EQ hugs the bass so well because he's put in a massive +10dB of gain in some areas of the bass (https://www.dropbox.com/s/zr5tqw0qojom9uh/Sennheiser HD650.pdf?dl=0 ) whereas in the HD600 he limited it to a max of +5dB. Technically he could have done the same with the HD600 for that +10dB boost, but I'm imagining that it didn't play nicely with the headphone. Solderdude's distortion measurements show HD600 to have slightly more distortion sub 100Hz than the HD650, so that might be the reason Oratory couldn't do a 10dB boost for the HD600. Although the difference in distortion seems only slight to me between the two headphones, so praps it's not that.....it is interesting though considering I think the HD600 & HD650 use the same drivers, they're just tuned differently right?
