Omega_ELS

a huge amount of work has been done...

So they just stole the design and didn't even ask permission before selling it for 20k euros?

Well, there are true portable amplifiers, for example, the Stax D10, but its runtime is 3.5 hours. Which is pretty funny. This HVRV can also be used with some kind of 12V power bank of a similar size. But then we have to carry two boxes. And why do we even need portable amplifiers.. Almost all Stax headphones are open-back. Unless we using a Stax 4070. But I think only a few people in the world have such a setup. Probably no one does. It's much more promising to simply have a portable, small amplifier that we can easily take on a trip, for example, put in a suitcase. The 10 kg kgsshv is hard to fit in a suitcase. And this one is just right.

Well, let's be honest, it was never portable. It consumes 600ma + more like 800+ for DC converters. No small battery can handle that—for example, 10 hours. Yes,we can use a power bank, but that won't be very portable.

Mine works without any problems. I tested it for 12 hours straight. Yes, it's quite hot. But all the heat is dissipated by the case. Power supply: +-400V. 5mA current consumption. 12V input. 1-2A power supply required. I'd say the sound is on par with KGSS, definitely not worse.

The main problem with the 009 is the driver size. They're simply smaller than the ES Lab or x9000. And the detail isn't as good as the x9000. If the 009D is the same as the 009, only for 2k+, then what's the point of buying it now? It's better to wait.

I would definitely buy one of these or similar ones, but no one sells them.

After reviewing the Spritzer and seeing the internals a few years ago, I was put off buying the JR. But now that I've listened to almost every full-size es earphone, JRs priced under 2,000 seem like such a not very bad buy to me. Don't they have a mesh stator, similar to the Omega 1 and X9000? seems they should sound good.. I would also be very interested to see the SR driver and what's inside...

already on sale for 350k

So, I've been testing it for two days. It's thermally stable for 12 hours. I think the tests can be completed. I just don't know what the upper power limit is. I tried +-400V and it works. And even at +-450V. I wonder if it can withstand +-500V or 600-700-800V? I saw someone build it with four 400V modules. So, +-800V.

Hi Kevin Well, it still works. It's just that the voltage distribution isn't ideal for -400V and +400V. I'm not sure if it's possible to supply different voltages. The sound is good and quite clear. But I think I'll still have to buy those proper modules and settle the power supply issue—there's no way to get +-400V 6mA for under $50.

So I connected this yellow DC-DC. It can produce -400 and +380 volts from 12 volts. Which is 20 volts less than I need. Interestingly, it can produce -400 volts in one side. And only +380 volts in the other. Funny. Now I'll be looking for ways to squeeze another 20 volts out of it. Or should I just skip the hassle and buy some decent USA S400 modules and be done with it.....

Well, if I turn the volume up to maximum, the amplifier can consume up to 10 mA at peaks, but I don’t listen that loud. I dont know if its minited to +-400v or maybe it can handle more.

Yes, you're right. That's why I had to connect it like this. I'll get this thing tomorrow 12v to +-390v DC DC I hope it doesn't beep or at least there's a way to eliminate the beeping with an RC filter or something. I'm just trying to try all the DC-DC modules before spending $50+ on those cool USA12400S-8 ones. But most likely, I'll just have to buy them.

It's been working reliably for an about hour now.I will continue testing 24\7. The power consumption of the modules themselves from the 12V power supply is 550 mA under load. The power consumption of the amplifier itself from these modules at +-400 V is only 5.5 mA.

i use 4 of this one https://www.lcsc.com/product-detail/C5279972.html DEXU Electronics B1212LS-1WR3 it's something like galvanic isolation

https://www.ebay.com/itm/275736642694 its max MAX1771 12v to 150-220v DC it can be ajusted i set 200v and just connected it 200+200 for +400 and 200+200 for -400 I read a similar problem about noise here but I couldn't find a solution. Well, unfortunately, I don't have a thermometer or pyrometer, but it feels like it's probably about 45 degrees Celsius or so - maybe more/less, It dissipates pretty well.

Hi Kevin. Thanks for your reply. The boards are sandwiched together with a thermally conductive material and a bunch of thermal paste between the housings. I couldn't figure out an easy way to get inside without breaking everything. I'm hoping the problem is still in the power supply, since you're right—it was heating up. The diodes were burning out frequently, then the transistor itself, and then possibly the transformer itself—its resistance is now 0.1 ohms on the primary winding and 4 ohms on both secondaries. I'm not sure if that's normal. It's been working without any problems on a third-party power supply for half an hour now. I'll continue testing. I couldn't think of anything simpler or better than connecting 4 of these modules to get +-400v To my surprise, these modules produce even more than 10mA and +-400v But they have one major drawback: noise. The throttles in them make noise.

Thanks for your message. Then I'll try building a cheap power supply with 4 DC-DC converters (i have some for 200V) and test its stability when running 24/7. And only if it runs 24/7 will I order those power supplies. They're quite expensive at $25 each, and i need two of them, which means $50 plus bias.

Sorry if I posted this in the wrong thread. But it seems like this is also a clone of this amplifier. You're talking about the amplifier board itself overheating, right? That is, the resistors on it are drifting and therefore i need to be replaced with ones with greater thermal stability... This is where the power supply failed, and I've already ordered the DC-DC converter that Kevin recommended. I hope everything works reliably after installing them. I initially thought that the problem with this thing was in the power supply, but now I realized that it’s not that simple...

Yes, but they say in the ad that the sound is different. Maybe the membrane is different? The 007 mk1 and mk2 are almost identical in appearance. But the sound is very different. Maybe it's the same story here.

I'm more interested in the difference between the MLER 3 and the MLER2, since the stator shape, judging by the photo, is the same.

NEW PRODUCT New Product News – November 2025 STAX SR-009D electrostatic headphones The pinnacle of high-end headphones – electrostatic headphones with detachable cable design, offering an even wider soundstage We proudly announce the new flagship STAX model: **SR-009D**. The first model with a detachable cable structure, delivering further sound quality improvements. Compared to the previous SR-009S, it increases the amount of sonic information, enhances detail, and expands the soundstage. Equipped with the newly developed **MLER3** driver and a dedicated cable for the 000D, it achieves extreme transparency and resolution. **■ MLER3 Driver (New)** The newly developed **MLER3 (Multi Layer Electrodes 3)** driver was created exclusively for the SR-009D. Compared to the previous MLER2, it delivers more sonic information, improved detail, and a wider soundstage. The MLER3 features an enhanced electrode mounting method, ensuring more uniform diaphragm vibration and reducing distortion to an absolute minimum. This results in transparency and resolution that surpass previous models. **■ Detachable Cable Support** The SR-009D is the first STAX model to support cable replacement. It comes with a newly developed dedicated cable for the 000D. Cable swapping allows sound tuning and customization to personal preferences. Additional official STAX replacement cables will be released gradually. **■ Launch Campaign (Until End of December 2025)** All customers who purchase the **SR-009D** will receive the official **SPC-009** cable (retail value: ¥55,000 incl. tax) as a gift. Every buyer during the campaign period will receive the SPC-009 cable free of charge. Limited quantity – early reservation recommended. **Campaign Gift:** 1.5 m official OFC headphone cable **Specifications:** - Type: Push-pull open-back electrostatic headphones - Frequency Response: 5 Hz – 42,000 Hz - Electrostatic Capacitance: 110 pF (including cable) - Impedance: 145 kΩ (at 10 kHz, including cable) - Sound Pressure Sensitivity: 101 dB / 100 V r.m.s. / 1 kHz - Bias Voltage: DC 580 V - Left/Right Indicators: L / R - Ear Pads: Genuine leather (lambskin), partially synthetic leather - Cable: 6-core parallel silver-coated 6N OFC + silver-coated copper wire - Weight: 454 g (with cable) / 383 g (body only) **STAX Co., Ltd.** 33-1 Honcho, Wako-shi, Saitama 351-0114, Japan TEL: (048) 483-1801 FAX: (048) 293-1802 URL: https://www.stax.co.jp are your ready for new 009D?

Hello Are these converters quiet? thanks for reply Is there a difference between the USA24400S-8 or the USA12400S-8? They differ only in the input voltage. Do they create a buzzing sound in the headphones, as is usually the case with cheap DC-DC converters? Can they be used to power an amplifier with +-400V? My HVRV power supply just broke. I'm thinking of installing two of these USA12400S-8. thanks for reply or any information. By the way, here's the HVRV board. I think he was inspired by Kevin's amplifier idea—the photo shows the same 20 transistors, 4 capacitors, and resistors.