Dan Clark Expanse Headphone Review

[Zenairis]

Your 'gentle' translates to low sensitivity and lack of gain in an amplifier in technical terms.

Considering my first set of test was on a Oor/Hypsos I would not say my test were a lack of amplification even if it wasn’t mentioned. You only have a few amps that push more than that without going speaker build.

I just wasn’t a fan of the Oor so I sold it in favor of the A90D

On the bright side I will have an Expanse coming in a couple of days.

 

[solderdude]

Amps do not 'push' they provide a voltage and the headphone draws current. It is either limited by voltage or current limits.
Your 'pushing' translates to having enough (voltage/current) headroom to spare at loud volumes.

That said with 98dB/V the sensitivity is very, very low and combined with the low impedance (around 20ohm) it requires quite a lot of power to play impressively loud (120dB peaks). For that you need at least 13V and 0.6A = 8W so requires quite a beefy amp.
This can be reached driven from a 40W in 4ohm speaker output (20W in 8ohm).
A phone or a 'regular' headphone amp may well be able to drive the Expanse to long term enjoyable levels but not impressive levels. It requires a LOT of power to be available.

Do enjoy the Expanse. Maybe one day I'll head off to Delft and listen to the Stealth and Expanse (and many other goodies)

 

[Robbo99999]

A number of ASR members have hoped for a "Junior Stealth" or a "Junior Expanse", that uses the AMTS technology on a less-expensive headphone. I may be wrong, but I wonder why DCA would do that. Given their sunk costs in the technology as a smallish company, they seem to be able to charge quite a bit for their best headphones. Gearing up for selling more units of a new model at lower prices would require investment, and undercut sales of the premium models. I wonder if they would hurry in that direction as long as their Stealth/Expanse sales hold up, and most of the reviews have been positive.

Maybe in a few years they'd do that, if headphone competition amps up and once they've got back their return on investment for their expensive models.

 

[Grobbelboy]

O

Amps do not 'push' they provide a voltage and the headphone draws current. It is either limited by voltage or current limits.
Your 'pushing' translates to having enough (voltage/current) headroom to spare at loud volumes.

That said with 98dB/V the sensitivity is very, very low and combined with the low impedance (around 20ohm) it requires quite a lot of power to play impressively loud (120dB peaks). For that you need at least 13V and 0.6A = 8W so requires quite a beefy amp.
This can be reached driven from a 40W in 4ohm speaker output (20W in 8ohm).
A phone or a 'regular' headphone amp may well be able to drive the Expanse to long term enjoyable levels but not impressive levels. It requires a LOT of power to be available.

Do enjoy the Expanse. Maybe one day I'll head off to Delft and listen to the Stealth and Expanse (and many other goodies)

Hmm, so driving the Expanse with a Topping L30II won’t get the best out ‘em by a long shot? I was going to listen to them in store and most likely purchase them this week, but wasn’t planning on upgrading my dac/amp just yet

 

[staticV3]

@Grobbelboy
The L30II can output about 9Vrms into the Expanse before clipping, at frequencies where music is loudest (bass).

That'll give you 94+20*log10(1/0.665) + 20*log10(9) = 116.6dB SPL peak.

For reference, 115dB SPL is very loud already.
On my HD600 my regular volume is about 80dB SPL peak, or about 8% the perceived volume that the L30II+Expanse is capable of.

 

[Grobbelboy]

@staticV3 Great, that’s very useful. Thank you!

 

[solderdude]

Yes, You can play very loud with that amp. Just a few dB short of the theoretical 120dB limit.

115db peak = about 95-100dB average which is quite loud.
The Expanse is a very inefficient and not sensitive headphone.
This means only to reach uncomfortable loud peak levels without any clipping you need to have a lot of power available.
To reach loud levels about 110dB peaks are needed and this only requires 4V (0.8W) in 20 ohm
To reach comfortable loud levels about 100dB peaks are needed and this only requires 1.2V (80mW) in 20 ohm
A phone can only provide about 97dB peak with the Expanse = about 80-85dB average.

So you only need more absurd power levels to reach 120dB SPL which is what rarely anyone ever needs/uses/does.

 

[DilbertPugh]

I've been reading this thread avidly, even though I'll never be able to afford them nor with my advancing age, ('Dad, why is the telly on so loud!") do them justice.

However I really appreciate the technical advance it represents and feel sure that trickle down will see it reach lower priced headphones in the future.

As I have been reading the comments (wasting my time according to my wife who has a list of things I could be getting on with!) I realise I've been listening to music on Dan Clark Drop Aeon Closed Back Headphones played through the tiny Topping E30/L30 stack. They sound fantastic to me and the comfort is second to none; I'm in heaven.

Having watched Dan Clark talking about the company and their products it's clear that he's a genuine 'Diamond Geezer' as we used to say in Blighty. If Dan says the Expanse is worth $4000, given the competition at that end of the market, I absolutely believe and applaud him, building a top tier company with great customer service in the USA doesn't come cheap.

 

[Jave]

Do these also require perfect seal for good bass?

 

[NMixes]

Do these also require perfect seal for good bass?

For me, yes. not sure if the pads are going to soften with use

 

[ObjectiveSubjectivist]

For me, yes. not sure if the pads are going to soften with use

They, will.
I'm using Stealth for quite some time, and pads did soften hence seal improved.

 

[oscar_dziki]

I placed an order yesterday. Was planning to make this my Christmas gift for myself, but I was so scared of inflation and price of dollar that I hurried it up a bit. I need to wait for them about 10 days now. I guess I might be one of the first owners in Poland that's exciting I must admit. I guess I will not buy anything for a year now Also I hope that my E30 II L30 II combo will be sufficient.

 

[Grobbelboy]

I expect them to arrive here today and will drive ‘em with a DX3 Pro+ as DAC and L30II as amp. I’ll try to post some impression asap.

 

[oscar_dziki]

I expect them to arrive here today and will drive ‘em with a DX3 Pro+ as DAC and L30II as amp. I’ll try to post some impression asap.

Cant wait to read it I can still change my ordered cable to a balanced one if e 30 II is not enough, although I would be surprised

 

[Rthomas]

Yes, You can play very loud with that amp. Just a few dB short of the theoretical 120dB limit.

115db peak = about 95-100dB average which is quite loud.
The Expanse is a very inefficient and not sensitive headphone.
This means only to reach uncomfortable loud peak levels without any clipping you need to have a lot of power available.
To reach loud levels about 110dB peaks are needed and this only requires 4V (0.8W) in 20 ohm
To reach comfortable loud levels about 100dB peaks are needed and this only requires 1.2V (80mW) in 20 ohm
A phone can only provide about 97dB peak with the Expanse = about 80-85dB average.

So you only need more absurd power levels to reach 120dB SPL which is what rarely anyone ever needs/uses/does.

Do you think the RME-ADI 2 DAC can get the full potential of the Stealth and Expanse?

To my ears the Stealth gets very loud from the RME but I wonder if I can get better performance (especially bass performance from something like a Topping A90D)

Just for info I'm not using any EQ and I don't think I listen very loud. I use less than 50% volume on most consumer NC headphones like the Bose QC35

 

[Grobbelboy]

So the Expanse came within 10 minutes after that last post. So far I’ve listened to them for an hour or three.

The L30II drives them more than loud enough. On high gain I never have to turn the knob past 12 o’clock on the vast majority of music to listen plenty loud. Only on albums with a low master volume like the My Bloody Valentine or Pixies discography I had to go past it - but still never got near maxing out the volume. At the moment I’m even listening on medium gain with the knob around 3 o’clock on most tracks, to minimize channel imbalance.

I won’t go too deep into my subjective impressions yet because I’ve only had one (more or less) continuous session with them, but the long and short of it is that they sound fantastic. I traded in the Noires for these, which I overall liked but where the upper mids and treble didn’t quite work for me on some tracks. On the Expanse the whole frequency spectrum convinces completely. There’s an enveloping fullness to the sound that I haven’t heard in a headphone before. I also have no idea where the people claiming these things lack bass or “slam” (ugh) are coming from. As I’m typing this the album ¡Ay! by Lucrecia Dalt is playing and I’m continually amazed by the rendition of the lower frequencies.

Another thing about bass: the bump between 100 and 200 Hz (deviating from Harman) works great on most tracks but indeed can make some already “warm” music sound just slightly muddy, as Amir noted in the review. Gonna try out the EQ filter that Dan Clark provided over on head-fi soon:

to adjust the Expanse tonality to get closer to Stealth PEQ 175Hz, Q=2.6, -2.5dB.

Something I’m (perhaps needlessly) concerned by is the slight creaking/crackling sound coming from both cans when I put just a bit of pressure on them. It doesn’t occur on any other occasion so isn’t a problem during regular listening, but I’m wondering if it’s just a normal phenomenon when the planar driver gets flexed, or something to be more worried about. The Noires or Hifimans that I’ve had never did this. Would be nice if someone could go into this.

 

[oscar_dziki]

Something I’m (perhaps needlessly) concerned by is the slight creaking/crackling sound coming from both cans when I put just a bit of pressure on them.

My guess is that's a similar problem, as some cheap dynamic iems have with the driver bottoming out under air pressure. But I'm just guessing.

Thank you for this quick review. I feel better about myself now for picking relatively cheap e30 l30 combo to drive them. This will be amazing to get away with 300$ gear that drives them to their fullest.

 

[oscar_dziki]

So far I’ve listened to them for an hour or three.

Seems like it was a good listening session

 

[solderdude]

full potential of the Stealth and Expanse?

It depends on what you mean by 'full potential'
A90D can output 10W (balanced out) and 2.5W in SE mode.
The ADI2 DAC can do about 1W in 20 ohm.
So the A90D can reach higher peak levels. At 97dB/V the ADI-2 can reach 110dB peak SPL (so about 90-100dB average) and the A90D (balanced) can reach 117dB so can go quite a bit louder.
I would assume you value your hearing and don't EQ the DCA so would expect you will always remain below 1W in which case the A90D has no benefits.
But on occasional 'let's see how impressive this headphone really is' moments and you crank it up with music that has a ton of bass in it then chances are you may be clipping the RME and would not yet clip the A90D. In that case one could say the A90D may be worth the extra expense.

 

[solderdude]

Something I’m (perhaps needlessly) concerned by is the slight creaking/crackling sound coming from both cans when I put just a bit of pressure on them. It doesn’t occur on any other occasion so isn’t a problem during regular listening, but I’m wondering if it’s just a normal phenomenon when the planar driver gets flexed, or something to be more worried about. The Noires or Hifimans that I’ve had never did this. Would be nice if someone could go into this.

It is normal for this headphone. It has to do with the sealed front volume. The amount of air trapped between the head and driver as it were.
When the headphone is on the head and has a good seal and then you push it onto the head a bit more the air compresses and pushes the driver to the back (momentarily).
Dan makes the drivers a bit different than the usual planar manufacturer suspects which allows for a bigger 'swing' at higher SPL for the lowest frequencies.
The membrane is sort of 'wrinkled' to allow a larger swing, while other manufacturers 'tension' the membrane and have to rely on the flexibility (stretch) of the membrane.
Think off the 'spider' in a loudspeaker to get an idea.
For this reason, when you put some pressure on the driver, it is pushed to maximum excursion (at that moment) but cannot go further. That's the wrinkle sound you hear.

An LCD also has the same thing happening (suction cup effect) but here you only hear the bass disappear shortly (as the membrane stretches maximum).

Once the air pressure in front and rear of the driver is the same (there is always some leakage) the membranes swing from the 'neutral' position again and all is fine.
I would expect the 'intentional' wrinkles in the DCA membrane to get back into their original shape.

A lot of headphones either have a 'pressure equalization hole' in the baffle or some other material that can pass air or have pads that can (slowly) pass some air.

For the same reason most closed headphones either have a small hole in the cup to the outside (or front volume) to prevent the driver from becoming a 'barometer'.