Introducing the CORINA Electrostatic Reference Headphone

[mrspeakers]

@mrspeakers: Question to Dan: You have proven with the Stealth and E3 that you can build really great sounding close back headphones.
Any thoughts on developing a closed back estat?

This would really fill a gab, as to my knowledge there is only the very old (and ugly) Stax 4070 "available".
Maybe this "gab" is not very big in terms of market demand?
Since the ZMF closed back and your E3, I am totally back into closed back headphones. For me, CB are closer to the original intention of a headphone (or at least my intention) of not being disturbed and not disturbing others when listening to music. I switched only to open back headphones because for a long time there were no good CB headphones around.
A CB estat would be totally a dream come true for me.

We have made some experiments but were not pleased with the system performance, frequency response was too hard to control in a cup and the magic went away.

 

[TheAbyss2022]

I have made the Corina my next priority to pick up.

I already have the Stax 009, 009S & CRBN and hopefully the Corina runs well on the iFi Phantom as it drives the other headphones really well.

 

[mrspeakers]

iFi Phantom

They don't publish the output voltage swing, only the bias which they incorrectly state as 640V RMS when it's 640V DC. So hard to say.... The Corina is less efficient than your other headphones because it has a slightly larger stator gap due to the very large driver size. Let us know how it works for you...

 

[etc6849]

I'm really digging these. Only drawback is these are about the only other electrostatic I have that is this hard to drive except for the Stax X9000's. Good thing I have a really big energizer I built running off two Benchmark AHB2 amps

 

[JLoud]

Now that is a crazy amp! Tim Tool Time Taylor would be proud.

 

[etc6849]

Thanks! The bias circuit is pretty easy to make if you have experience and the equipment. Out performs every bias circuit I've measured so far. It's the one explained in this video:

 

[etc6849]

@TheAbyss2022

None of the little transformer based boxes can do ~1600Vpp like the BHSE or a custom box with large transformers can. It's all manufacturer hype. This is what is required to drive these large estats to peak performance (IMHO).

The small transformers go into saturation and simply cannot handle lower frequencies like larger transformers or a proper electrostatic amp can. Try to measure one of these small boxes at 10, 20 and 30Hz. You'll see quickly that the sine wave is distorted even at say 500Vpp and 20Hz, and much more distorted at say 10Hz and ~500Vpp.

Some measurements of my large transformer setup:
10Hz, a little distortion (not present at 10Hz on the BHSE):

20Hz, 2kV peak to peak! Beating out many electrostatic amps in terms of peak voltage:

Now that is a crazy amp! Tim Tool Time Taylor would be proud.

 

[aokman]

They don't publish the output voltage swing, only the bias which they incorrectly state as 640V RMS when it's 640V DC. So hard to say.... The Corina is less efficient than your other headphones because it has a slightly larger stator gap due to the very large driver size. Let us know how it works for you...

Phantom is basically an iESL (transformer based) with a weaker driving amplifier so I wouldn’t expect miracles.

I wish there were places to demo Corina in Australia, would love to try one with Lundahls and the new pro bias setup before I purchase my high end pair.

 

[Svperstar]

@TheAbyss2022

None of the little transformer based boxes can do ~1600Vpp like the BHSE or a custom box with large transformers can.

Someone measured the BHSE in a thread on here recently and they only got 1500 Vpp. Matching the original Blue Hawaii. Only a 6% difference regardless

 

[etc6849]

Yep, I've posted similar measurements in that thread too. When I say it can at least do what it says it can, I meant within +/-6% Unlike all of these little boxes that claim 640Vrms and 5Hz-50kHz +/-3dB response, but when you measure them at 30Hz and lower, you see you will never get 640Vrms, and things just distort more and more the lower you go in frequency, and the higher you go in output.

Someone measured the BHSE in a thread on here recently and they only got 1500 Vpp. Matching the original Blue Hawaii. Only a 6% difference regardless

 

[etc6849]

I finally found a site with EQ settings for the DCA Corina. However, the https://squig.link site will not let me use high or low shelf filters, only peak/bell shelf filters with the AutoEQ feature.

Regardless, this is probably the best I'm going to get.

I'm still hoping someone sends their headphones to @oratory1990. @mrspeakers I'm not sure if he allows manufacturers to send in headphones, but I really like oratory1990's EQ settings on my other headphones: https://www.reddit.com/r/oratory1990/wiki/index/list_of_presets/

Not sure what measuring equipment @vsg28 uses and how it compares to oratory1990's?

https://vsg.squig.link/headphones/?share=Dan_Clark_Audio_CORINA

 

[vsg28]

I finally found a site with EQ settings for the DCA Corina. However, the https://squig.link site will not let me use high or low shelf filters, only peak/bell shelf filters with the AutoEQ feature.

Regardless, this is probably the best I'm going to get.

I'm still hoping someone sends their headphones to @oratory1990. @mrspeakers I'm not sure if he allows manufacturers to send in headphones, but I really like oratory1990's EQ settings on my other headphones: https://www.reddit.com/r/oratory1990/wiki/index/list_of_presets/

Not sure what measuring equipment @vsg28 uses and how it compares to oratory1990's?

https://vsg.squig.link/headphones/?share=Dan_Clark_Audio_CORINA

The measurement equipment and process is all mentioned in my reviews, for example here in my most recent DCA headphones review (scroll down to the Frequency Response Measurement and Listening section): https://www.techpowerup.com/review/dan-clark-audio-e3-closed-back-headphones/4.html

 

[etc6849]

Thanks to VSG for helping! I ended up with the EQ settings for the DCA Corina.

These sound incredible to me, but honestly, the Corina like the Expanse just sounds incredible without EQ too By far, my favorite headphones.

In case someone wants to use my settings derived from VSG's measurements and generated from autoeq.app, I ended up with the settings on the left for RME TotalMix Room EQ (I'm using an RME UFX III audio interface), but note I added +5.1dB to the preamp level compensate for using a -5.1dB high shelf filter in place of the +5.1dB low shelf filter. I did this as I have several headphones stored in RME TotalMix, and like to keep the overall preamp gain offset around -2dB... I could have had autoeq.app generate two high shelf filters and one low shelf (limitation of the room eq in RME TotalMix is one low and two high shelfs, the other 6 bands are peak/bell), but this probably would have meant using a higher preamp offset.

For most, they can just copy the custom PEQ settings on the right and use -6.8dB preamp gain if they want to try these. Sounds incredible to me.

Upon googling, I also figured out we can use curve fitting as well to extract measurement data from an image, then import these into the autoeq.app site:
https://medium.com/@jaakkopasanen/make-your-headphones-sound-supreme-1cbd567832a9

The measurement equipment and process is all mentioned in my reviews, for example here in my most recent DCA headphones review (scroll down to the Frequency Response Measurement and Listening section): https://www.techpowerup.com/review/dan-clark-audio-e3-closed-back-headphones/4.html

 

[ducanh712]

I think DCA Corina have the best vocal reproduction to date. Great headphone

 

[TheAbyss2022]

I think DCA Corina have the best vocal reproduction to date. Great headphone

What about the BASS?