Tachikoma

Yep, they're dark brown-colored and hard, so they are most likely Lambda Signature pads. Anyway, the EP-507 and Lambda Sig pads are fairly close, just a small tradeoff between airiness (Lambda Sig) and tonal density (EP-507).

I'm just assuming that they're stock pads, got them with my LNS many years ago. There is a little decomposition, but its slight. They're pleather too, but a much harder pleather. They seem a lot less permeable than the 303 pads.

Since this thread isn't heading anywhere... I did a little comparison between three Lambda pads on the SR-303: Stock 303 pads, EP-507 pads and Lambda Nova Signature pads. Stock 303 pads: Detailed and airy, but shouty. Yuck. EP-507 pads: Hmm, the shout is gone. The sound has decent tonal weight now. Note: The EP-507 is actually a bit smaller than the other two. Lambda Nova Signature pads: No shout here either, a bit more airy than the EP-507 pads. Favourite pads so far. I wonder if the old "303/404 shout" is actually caused by Stax's pleather pads, rather than some inherent flaw in the driver. This could also explain why the 404 limited sounds better, as it uses leather pads instead of pleather.

https://www.audiosciencereview.com/forum/index.php?threads/topping-l30-headphone-amplifier-review.15226/page-150 headphone killers maybe...

Oof. Given the magnitude of the imbalance, you may have changed (increased) the stator spacing when reassembling the driver. Just try assembling it again, but this time with some gentle pressure on the stators. A small wound should not induce such a large imbalance, nor will a little foreign matter. Another possibility is that the diaphragm was installed the wrong way... I'm not sure why it matters, but it sometimes does.

I suppose it wouldn't be possible to make the bias voltage switchable?

Holy shit. I think the EP507 was about half that price when I got my pair. I've heard nice things about Vesper audio, they are probably the nicest looking 3rd party earpads you can get. Its that or the adapter I guess.

https://www.headamp.com/products/headamp-pico this, perhaps? There are so many IEM-friendly options nowadays. You don't actually need "negative gain", just a low gain option.

Actually, if you adjust the voltage between GND and VCC to 800V or higher (the voltage between 200V and VCC/GND is around 500V at this point), the noise shifts beyond the human hearing range. Otherwise yes, they're really noisy. I'm using one for my transformer box - I can't hear any electrical or physical noise in its current configuration.

Just buy this instead, much safer than working with mains. https://www.aliexpress.com/item/1005001813099933.html?spm=a2g0o.productlist.0.0.41dab88epLfUCK&algo_pvid=27a95d58-360c-4aa9-943c-1a8140972e4b&algo_expid=27a95d58-360c-4aa9-943c-1a8140972e4b-43&btsid=0b0a557016094939405453680e2d15&ws_ab_test=searchweb0_0,searchweb201602_,searchweb201603_ Use a regulated 5V supply, and take the voltage between VCC (or GND, but VCC works better for me) and 200V as the bias (credit to Sajeev Ranasinghe (Nectar)).

There are a few other pads that allegedly work with the 007, like Kennerton Audio's ECL-01 and ECL-02, and ZMF pads (I know someone using ZMF auteur pads on a pair of 007s). Have you tried any of these pads?

https://www.head-fi.org/threads/headamp-grand-cayman-dht-electrostatic-amp.920536/ Whats this? :0

How does it compare to your direct drive amps? and do you have the Lundahl transformers in this unit?

I have tried equalizing using EqualizerAPO based on reference FR charts. It transformed my KSE1500 into a $5 earbud.

Will do