HD650 impedance/sensitivity vs HD600?

[cpw]

I'm looking to hook up two pairs of headphones to the same amp by using a splitter. I assume that if the headphones are identical, they'll produce the same sound/volume. Here's the question:
I currently have HD600s and am going to buy a second pair of phones. I'm considering buying HD650s but wonder if hooking them up simultaneously w/ the 600s would be problematic. Would I be better off w/ a second pair of 600s? I'd like to try the 650s but the 600s are friendlier on the wallet.
The amps are HR-2 and PPX3. Will both of these work ok w/ two pair of cans attached?
Thanks,
CPW

 

[john_jcb]

The 600's and the 650's are virtually identical as far as an amp is concerned; it is really up to you and how much you want to spend. Where the problem comes in is if for instance you wanted to use Grado's and HD600's at the same time. It would be next to impossible to adjust the volume so that it was identical.

I know the HR-2 can power multiple pairs of 600's at the same time. I forget how many but 2 is definitely not an issue.

 

[JaZZ]

Hi Lewis!

HD 600 and HD 650 have about the same impedance (curve) and sensitivity. Connecting four HD 600s and four HD 650s to the same amp is like connecting one CD 3000 or R10 -- impedancewise. So two HD 6X0 are no problem for any amp.

Good idea to try the HD 650!

 

[Kush_]

CPW: I know this is a little off topic but i was wondering which amp you perferred, the ppx3 or the HR-2? (assuming you own both amps)
Hopefully i will be buying myself a HR-2 one day when my financial situation it a bit better.

 

[olesth]

The transducers in HD580/HD600/HD650 are identical - see the spare parts numbers on Senn's homepage. The only difference between the three are subtle details of the acoustic chambers, allegedly the matching between left and right transducers, then of course the finishing and packing - and the price.

 

[Sugano-san]

Couldn't find the spare parts list on the German Sennheiser pages and would be grateful if you could provide a link.

I note, however, that Sennheiser quote a 103 dB SPL for the 650s as opposed to only 97 dB for the 600s. Do you think that's due to the "subtle details of the acoustic chambers, [...] the matching between left and right transducers, [...] the finishing and packing - and the price?


Quote:

Originally Posted by olesth The transducers in HD580/HD600/HD650 are identical - see the spare parts numbers on Senn's homepage. The only difference between the three are subtle details of the acoustic chambers, allegedly the matching between left and right transducers, then of course the finishing and packing - and the price.

 

[JaZZ]

Quote:

Originally Posted by olesth The transducers in HD580/HD600/HD650 are identical...

The HD-650's membranes are newly developed. See this article that reproduces some of Sennheiser's own announcement-text points (unfortunately not available anymore).

 

[cpw]

Quote:

Originally Posted by Kush_ CPW: I know this is a little off topic but i was wondering which amp you perferred, the ppx3 or the HR-2? (assuming you own both amps) Hopefully i will be buying myself a HR-2 one day when my financial situation it a bit better.

You'll likely love the HR-2; I love mine.
The PPX3 is still 4-5 days out but I'm really looking forward to it. With any luck I'll have it by Sat or Mon. Can't wait to try it.
As to which I prefer, I'll need some time to know for sure but I'm hoping to like them both for different reasons.
CPW

 

[olesth]

Quote:

Originally Posted by Sugano-san Couldn't find the spare parts list on the German Sennheiser pages and would be grateful if you could provide a link. I note, however, that Sennheiser quote a 103 dB SPL for the 650s as opposed to only 97 dB for the 600s. Do you think that's due to the "subtle details of the acoustic chambers, [...] the matching between left and right transducers, [...] the finishing and packing - and the price?

Here is a link (german). They list the transducers for HD580/Jubilee/HD600 as part number 49294:

http://www.sennheiser.com/sennheiser...ile_kopfhoerer

The HD650 is not in that list at all, however. I read this regarding the HD650 a while ago in a posting here. It said that a Senn support recommended to order the HD580 transducers as a spare for HD650 because they are identical but cheaper on their list. I can't find that posting now because there are really a LOT of postings regarding these phones, though.

So if you say that the HD650 is more efficient, then this is probably wrong. Good to know, anyway.

Regarding the press release for HD650, it just mentions newly developed "acoustic silk", without saying where they use it. Could be the diaphragm, or possible just the protective cover of the transducer - they have something similar in the HD580/600.

 

[StevieDvd]

Being a lateral thinker could it not be simply the case that the HD650 parts are being used as spares for the HD600/580 as it's cheaper to manufacture just the latest driver instead of making older models?

So perhaps a good upgrade for older 580s?

No idea if this is actually the case I'm just thinking out loud

 

[Sugano-san]

Quote:

Originally Posted by olesth Here is a link (german). They list the transducers for HD580/Jubilee/HD600 as part number 49294: http://www.sennheiser.com/sennheiser...ile_kopfhoerer

It's been known for a while that the drivers in the headphones mentioned above are identical types. That's probably why some find that there is no fundamental sonic difference between 580 and 600.

Quote:

Originally Posted by olesth [...] in a posting here. It said that a Senn support recommended to order the HD580 transducers as a spare for HD650 because they are identical

That's entirely possible, but not necessarily accurate.

Quote:

Originally Posted by olesth [...] the press release for HD650, it just mentions newly developed "acoustic silk", without saying where they use it. Could be [...] just the protective cover of the transducer - they have something similar in the HD580/600.

I think that's precisely what it is. Btw, I am a little skeptical regarding the meaning of the expression "acoustic silk", especially since I never heard it anywhere else before or after the HD-650s were introduced. Another marketing fad?

 

[Beagle]

Quote:

Originally Posted by Sugano-san /img/forum/go_quote.gif I am a little skeptical regarding the meaning of the expression "acoustic silk", especially since I never heard it anywhere else before or after the HD-650s were introduced. Another marketing fad?

I asked about this in the HD800 thread. It appears to be the black oval screen covering the drivers on front of the driver housing (which has since changed to a stiffer, silver material on the current HD650). This "newly developed acoustic silk" is also on the HD580 and HD600. So much for "newly developed". Looks like Sennheiser was engaging in obvious marketing hype (read:bulls--t). Who knows how much of what they say is really true regarding the HD800

 

[murrays]

Quote:

Originally Posted by Sugano-san /img/forum/go_quote.gif Couldn't find the spare parts list on the German Sennheiser pages and would be grateful if you could provide a link. I note, however, that Sennheiser quote a 103 dB SPL for the 650s as opposed to only 97 dB for the 600s.

The sensitivities are rated differently, so it's not apples with apples...
HD600 97dB @ 1mW (i.e. 0.548 V, 300 ohm)
HD650 103dB @ 1V (i.e. 3.33 mW, 300 ohm)
There is 6dB between the quoted sensitivities, but I make it only 5.2dB between the measurement levels. However, other factors (other than maths) may also affect the difference.

 

[QQQ]

NOT this again. Kill this thread!!

HD 650 a little easier to drie due to higher sensivity.

 

[Caution]

5 year old thread bump. Is this a new record? =D