[Chris J]

Quote:

Yo,
 
With the DT880/600Ohm since they are semi-open they will have a lower sensitivity. The general rule is more airflow - more sensitive, lower airflow - less sensitive. Since the DT880 is partially closed this makes them less sensitive. Even though beyer gives you the same numbers as the 600Ohm DT990 (600Ohm, 96dB) the sensitivity is actually lower. When I owned both, the DT880 was not as loud as the DT990 at the same volume setting on my amps.
 
All of these have more than enough power for the headphone, so they should be the natural choices. They are OTL tube amps, and as such they can output a large voltage swing an can drive higher impedance loads with ease. I've heard the DT880/600Ohm on a few of these (CSP2+, WA3, Crack) and it sounded beautiful.
 
About OTL:
OTL stands for Output Transformer Less, which means there is no transformer in the signals path nor is the amp coupled to one for buffering. The resulting output impedance of the amp is quite high and can be anywhere from 60 Ohms to over 100 Ohms. OTL designs generaly have a high voltage swing and are more efficient at driving high impedance loads. The high impedance will give some headphones a fuller sound and also gives you notice not to use any low impedance loads.

 
So the sensitivity (efficiency) varies from model to model?
Irritating!

Why can't they just tell it like it is!!!
Or is the DT990 apparently louder than the DT880 because it is brighter and the 96 dB @ 1 mW figure is referenced to 1 kHz?
But based on your statement, I assume the DT770 is the quietest of the 3? Which would ruin my brightness theory!
 
I see what you are getting at with the OTLs output voltage swing, but to clarify:
OTLs generally have more than enough voltage to drive high impedance phones but, in general, may not have enough current to drive low impedance 'phones. 
While the efficiency of an OTL will be higher when driving high Z (impedance) vs. low Z cans, a Solid State amp with a virtually zero output Z will be much more efficient than an OTL with any impedance 'phone.  This due to 1.  the high output impedance of the OTL and 2.  the energy needed to energize the tube's heater filaments.
 
Personally I prefer using my DT880/600 ohm with an OTL. This is just my personal preference; my soild state Matrix M Stage has more than enough output voltage to drive my DT880/600 ohm.

 

[stv014]

Quote:

Originally Posted by Zombie_X /img/forum/go_quote.gif
 
With the DT880/600Ohm since they are semi-open they will have a lower sensitivity. The general rule is more airflow - more sensitive, lower airflow - less sensitive. Since the DT880 is partially closed this makes them less sensitive.

 
My DT770 Pro is noticeably (2-3 dB) more sensitive than my DT880 Pro (both 250 Ohm), though, and measurements at doctorhead.ru show the same. I do not know how much random variation is there between pairs, however, because InnerFidelity shows the DT770-600 as being less sensitive than the DT880-600.

 

[Zombie_X]

I am not 100% certain but from my experience it seems that way. All DT models share the same base driver design but are tweaked accordingly. The DT990 has the same sensitivity rating as the others, but is much louder sounding at the same volume. The DT880 is quieter than the DT990 at the same volume, and the DT770 is even more quiet.
 
When I swapped the DT990 drivers into a DT770 enclosure, they were not a loud as when they were open. I always assumed cutting off some air choked them and made their sensitivity drop. I've heard this with Grado's as well (more airflow, more sensitive), it's listed on their website. But as I said, I am not 100% sure on this. 
 
On more theory I have is that all the models are rated different when it comes to sensitivity, but beyer only published the same 250Ohm, 96dB rating on all the boxes. This seems lazy IMO. I'll contact beyer and find out for sure.
 
And I agree with your statement about amps, I did not specify those in my initial post.
 
Quote:

 
So the sensitivity (efficiency) varies from model to model?
Irritating!

Why can't they just tell it like it is!!!
Or is the DT990 apparently louder than the DT880 because it is brighter and the 96 dB @ 1 mW figure is referenced to 1 kHz?
But based on your statement, I assume the DT770 is the quietest of the 3? Which would ruin my brightness theory!
 
I see what you are getting at with the OTLs output voltage swing, but to clarify:
OTLs generally have more than enough voltage to drive high impedance phones but, in general, may not have enough current to drive low impedance 'phones. 
While the efficiency of an OTL will be higher when driving high Z (impedance) vs. low Z cans, a Solid State amp with a virtually zero output Z will be much more efficient than an OTL with any impedance 'phone.  This due to 1.  the high output impedance of the OTL and 2.  the energy needed to energize the tube's heater filaments.
 
Personally I prefer using my DT880/600 ohm with an OTL. This is just my personal preference; my soild state Matrix M Stage has more than enough output voltage to drive my DT880/600 ohm.

 

[Chris J]

I am not 100% certain but from my experience it seems that way. All DT models share the same base driver design but are tweaked accordingly. The DT990 has the same sensitivity rating as the others, but is much louder sounding at the same volume. The DT880 is quieter than the DT990 at the same volume, and the DT770 is even more quiet.

When I swapped the DT990 drivers into a DT770 enclosure, they were not a loud as when they were open. I always assumed cutting off some air choked them and made their sensitivity drop. I've heard this with Grado's as well (more airflow, more sensitive), it's listed on their website. But as I said, I am not 100% sure on this. 

On more theory I have is that all the models are rated different when it comes to sensitivity, but beyer only published the same 250Ohm, 96dB rating on all the boxes. This seems lazy IMO. I'll contact beyer and find out for sure.

And I agree with your statement about amps, I did not specify those in my initial post.

Hmmmm, what happened to German efficiency? LOL
That's for the reply!

 

[Sonic Defender]

I'm happy to say that at a recent meet here in Ottawa, WullyMC auditioned my 880s (600 ohm) on my Valhalla and enjoyed the experience enough to buy his own 880s! Smart move from my perspective, I think the 880s are a really, really nice sounding headphone and I like helping others discover a sound that engages them. Cheers.

 

[flyfish2002]

Thanks, everyone.  For what it is worth, Rudostor assures me that the RPX-33 will drive the DT880 600ohm.  I know some here at Head-Fi  don't care for Rudistor designs or sound signature, but I have not yet come across a post regarding customer service.
 
If the RPX-33 does not work, I can alsways sell it and move to an amp that will - have my eye on this one as my Plan B:
 
http://www.frontendaudio.com/SPL-Auditor-120-V-Headphone-Amplifier-p/9999-06345.htm
 
Best,
 
Brent 

 

[Zombie_X]

IMO the DT880/600Ohm is a true bargain for how it performs. I think it performs higher than it's full MSRP.
 
Quote:

I'm happy to say that at a recent meet here in Ottawa, WullyMC auditioned my 880s (600 ohm) on my Valhalla and enjoyed the experience enough to buy his own 880s! Smart move from my perspective, I think the 880s are a really, really nice sounding headphone and I like helping others discover a sound that engages them. Cheers.

 

[wullymc]

Quote:

I'm happy to say that at a recent meet here in Ottawa, WullyMC auditioned my 880s (600 ohm) on my Valhalla and enjoyed the experience enough to buy his own 880s! Smart move from my perspective, I think the 880s are a really, really nice sounding headphone and I like helping others discover a sound that engages them. Cheers.

 
 

 

Thanks to Sonic Defender for the listening experience.  It definitely made my buying experience more relaxed having heard them before receiving them.  Now if I could only get my BH Crack.  It has been 7 1/2 weeks!
 
Quote:

IMO the DT880/600Ohm is a true bargain for how it performs. I think it performs higher than it's full MSRP.
 

 
 

 
Thanks to Zombie X for your youtube videos.  You really explained the differences in the Beyer 600ohm series well.  I really appreciate it.
And I too think they are a great value for dollar.

 

[BeyerFan]

The DT880/600 ohms is certainly one of the best (everlasting) cans that Beyerdynamic have come up with. Certainly punches well above its weight and is of great value considering it costs a fraction of the T1 but produces 80%-90% of the performance.

 

[Sonic Defender]

I would agree about the 880 seemingly producing a significant amount of the overall performance of the T1 for quite a bit less. I am considering a T1 as an upgrade in the near enough future as I think there is more detail and richness they will help me find out of the Valhalla (which I know is entry level stuff, but still really well designed and sounding IMO). I am also considering getting an SPL Auditor as a SS amp. I have been using a Graham Slee Novo lately which has really surprised me with it's performance. I'm not sure if Zombie X has any thoughts on say a Solo Ultra Linear instead of an Auditor with the 880s. Or anybody else of course.

 

[BeyerFan]

I suppose point of diminishing returns do apply when going up to the higher-end phones.
 
At least we can be rest assured that Beyerdynamic headphones will last a lifetime(except for the earpads which can be replaced with ease). On another thread here there were talks about the potential of wood cups on Audeze headphones exhibiting crack with time. Not exactly focusing on the Audeze but on violins, hence not exactly an apple to apple comparison. I wonder how existing Audeze users are coping with this concern.

 

[Zombie_X]

Sorry man, I've not heard the Solo Ultra Linear at all. I've heard the Novo, and while good, it was not impressive at all. The Auditor remains one of the strongest amp recommendations for the DT880 from me. It's raw power and authority of the DT drivers is unrivaled.
 
Also I feel that once you reach $1,000 amp range that diminishing returns are in full swing. An example I used is with the Liquid Fire, sure it sounds great but not $3,000 great. I would only say it sounds like it should be $1,500. The amp is not even revolutionary at all. I just fail to see why it gets so much good praise when it's so overpriced.
 
Quote:

I would agree about the 880 seemingly producing a significant amount of the overall performance of the T1 for quite a bit less. I am considering a T1 as an upgrade in the near enough future as I think there is more detail and richness they will help me find out of the Valhalla (which I know is entry level stuff, but still really well designed and sounding IMO). I am also considering getting an SPL Auditor as a SS amp. I have been using a Graham Slee Novo lately which has really surprised me with it's performance. I'm not sure if Zombie X has any thoughts on say a Solo Ultra Linear instead of an Auditor with the 880s. Or anybody else of course.

 

[Chris J]

Sorry man, I've not heard the Solo Ultra Linear at all. I've heard the Novo, and while good, it was not impressive at all. The Auditor remains one of the strongest amp recommendations for the DT880 from me. It's raw power and authority of the DT drivers is unrivaled.

Also I feel that once you reach $1,000 amp range that diminishing returns are in full swing. An example I used is with the Liquid Fire, sure it sounds great but not $3,000 great. I would only say it sounds like it should be $1,500. The amp is not even revolutionary at all. I just fail to see why it gets so much good praise when it's so overpriced.

Just a general comment here:

I would love to hear a pair of DTs or T1s driven by a Bryston HPA!

 

[Sonic Defender]

I ordered my Auditor today, in silver! I can't wait to have some hours with this amp. I will have to see if I love it so much that I sell my Valhalla, which I really, really like. I know many people have commented on the at times clinical nature of the Auditor, so my concern is that I may need to keep the Valhalla for times when I want more warmth (assuming I find the Auditor cold, which I really don't expect). My Rega CD player has a nice DAC in it that seems to give a slight warmth and I think the 880s are also coloured nicely toward a slight warmth so truthfully I am expecting to really be pleased with the Auditor.
 
Thanks for your thoughts Zombie X, I have read your review of the Auditor which frankly is what really helped me pull the trigger. Your review had depth without getting into hype. I read around the internet and the only people I found who didn't love their Auditor were Sennheiser owners (mostly HD 800) so with the Beyerdynamic signature I have, I am not worried at all. Have any of you who know the DT 880/Auditor combo sound also had the chance to hear the Valhalla/DT 880 sound? If so what are your thoughts? I guess if nobody else has these combinations I'll be able to post my thoughts from A/B. While I am still on the fence when it comes to the notion of burn-in (although reading Graham Slee's take on this I am far closer to accepting the idea) in your experience (anybody) how long a burn-in does the Auditor require and did you find much of a sonic improvement afterward? Cheers.

 

[liamstrain]

Quote:

While I am still on the fence when it comes to the notion of burn-in (although reading Graham Slee's take on this I am far closer to accepting the idea) in your experience (anybody) how long a burn-in does the Auditor require and did you find much of a sonic improvement afterward? 
 

 
With solid state components, I see little value - either in theory or experience. I'd just listen and enjoy the Auditor.