Pros: No problem with blu-rays with DTS HD-MA/TrueHD, clear crisp highs, good sound separation, HDMI passthr.,closed-ear to keep it quiet for your wife/kids
Cons: Overpriced? but the first to market (around 500USD)
Hey guys here are a few Japanese links in case they help. P.S. I am a football and hockey-playing English-speaking guy so sorry I can't translate haha:
Hi Head-fi fans,
First of all I must thank you for the incredible reviews and posts on this site. It has helped me a ton. I am by no means an audiophile of any sort but have been inspired by this site and the enthusiasts around. Now I have learned that there is no way that you get the quality of a high-end cabled headset in today's wireless world even in the expensive sets. So I realize that I needed a wireless set for convenience but I wanted to get something that supported all the newest sound formats while watching blu-rays such as DTS HD-Master Audio and Dolby TrueHD.
In this case though this review is mainly from the opinion of a guy who couldn't find any reviews on this product no matter how many hours I searched for one so I caved and picked-up a set. The Sony MDR-DS7500s are Sony's entry and first-to-market shot at HDMI wireless headphones (I know I have learned from you guys that we usually don't go for Sony for sound when you have dedicated companies like Senn and Hifiman, etc out there). But, all of a sudden with a wife who wants to sleep I find them probably one of the best purchases I have made in a while (to amature ears). Feel free to ask me anything or for vids and pics if you want. The box is a HDMI pass-through box so you can leave it off and still watch your TV, etc like usual. You can also power-up the unit using the headphones as well as switch inputs, etc straight from the headphones. TrueHD and DTS mode is noticeably clearer and sound separation/positioning is quite accurate. The bass and mids felt full and the soundstage, although I am not qualified to comment, felt pretty open especially when you were listening to a TrueHD or DTS HD-MA stream. The earpads seem to be nowhere near the size of, say the Sennheiser HD650s/800s but I found them perfect for my requirements (which was a quiet, closed-ear, comfortable set while sitting beside my sleeping pregnant wife LOL). The battery really does seem to last at least 15 hours between charges and I can blast the volume without distortion, however I think there is a very slight leakage at higher volumes. I think it charges fully in about an hour but sorry I haven't been around to completely verify the time from 0 to full charge. I find I am the type that hates a set if it muffles treble. This keeps the treble clear and crisp and had the feel (please don't kick my butt for being way too off) to an amateur like myself of the Hifiman HE300s. They are 50mm drivers so I found them pretty good overall. The earcups are nowhere near Sennheiser quality/comfort (ie: HD650s) but they are comfortable and the headset is sturdy. The headset turns on only when you have them on your head which saves the battery as well but if you slip them off or lean against a wall this could technically turn off the headset if you aren't careful (in my case this works perfect because that usually means I fell asleep so it might as well turn off haha). Wireless range was at least 50 feet as I walked through a few rooms without noticing any distortion.
My cabled reference points are the Senn HD595s through a receiver for DTS HD MA/TRUEHD as well as corsair vengeance 1500s on the pc prior to picking up the forementioned senns and the Sony MDR DS7500s. My wireless reference point are my buddy's Sennheiser RS 220s. Until the market floods with alternatives I find myself recommending this even though they are absolutely overpriced by at least 200 and definitely don't go into costco or bestbuy and buy an old outdated set for 300 like the RS1xxs. Ideally go with a cabled set through your receiver but if you have to go wireless I would recommend these over any other model up to February of 2012 and honestly it's nice to have all the audio standards supported in a comfortable wireless set. Oh yeah, I forgot to say that I live in Canada and I ordered these from Japan and got them in 9 days in perfect condition. Feel free to ask but I know I paid too much so I bet you can get them for a better deal.
A few other things:
Specific details on the headphones and tech:
I posted a question below and think I answered it: This is one of the most important parts to me. Hey guys. Does anyone know about the modulation for these headphones (I can't figure out the japanese manual haha). according to the Sennheiser RS220 manual, the RS220 modulation is 16-bit at 48kHz so no matter what source you use you will be limited to 48kHz and everything you listen to will be transmitted in 16/48. It would be nice if the Sonys have modulation at 24/96 or 24/192+? Any thoughts?
Google translate didn't do the best job of this but here is a cut-and-paste: "Also supports high-quality source with more than six times the amount of information about 192kHz, 24bit maximum". I take this as it supports 24bit/192kHz modulation (which sort of makes sense if it is a TrueHD or DTS HD-MA stream. I may have totally misinterpreted this but I think my conclusion (and google translate) is on the right track hah.
GAMING AND POSITIONING AND PROLOGICIIx and z
I tried it with MW3 (dolby digital) and FFXIII and XIII-2(dolby prologicII) and the positioning and surround feeling is really good. Obviously it is not a microphone headset so MW3 online would be useless. I also compared it to plugging my Senn HD595 into a turtle beach DSS dolby digital module (turns 2.0 headphones into positional dolbydigital/prologicIIz) through PS3 optical->turtle beach DSS->HD595 and found the positioning to be very similar. Of course the soft velour earcups of the Sennheisers win hands down and the size of the earcups. Going straight through my receiver to the Senn HD595 on dolby PrologicIIz settings (7.1 processing I believe?) resulted in almost identical sound separation between the Sonys and the Sennheisers, however the soundstage differences in the Senns was very slightly "wider" as you might expect. One more thing I would like to say on this is that I used to own a "true" 5.1 surround headset which means there are actually a bunch of individual wires that run from the headset to your receiver/PC/etc and individual speakers/drivers in each earcup. Those were the Tritton AX PROs in my case. I thought these Trittons above would give the best sound separation out of any headset because it most closely reproduced the speaker/driver situation of a surround sound system. In this case it actually wasn't very good because in my opinion the drivers were never balanced properly and one drowned out another and my ears couldn't make out a front left from a rear left (mainly because the drivers were so close to eachother). However, a dolby or likewise simulated headset is a mathematically calculated 2.0 headset so the positioning (especially for gaming) is far more accurate for the human ear to understand in my opinion. That's why I guess Tritton and many other companies came out with the AX 720s I guess? The positioning in the sonys are really good and the only thing you might not like once again are the slightly small earcup holes themselves (around 2 inch holes). Here's someone's pic where you can see the holes fairly well:
DOLBY HEADPHONE INFO
I have two dolby headphone comparisons that I will add to my review 1) PC Corsair Vengeance 1500 dolby with a blu-ray playing on dolby headphone mode and 2) my senn hd595 and 555s through a turtle beach dss module in dolby mode. Overall the MDR-DS7500s sound great in cinema prologicIIz and x modes and you get quite a clear and wide surround feel when using these modes. I still can't hear the height that prologicIIz claims to provide but I find it great. The DSS module adds almost an identical spatialization to the set-up. Keep in mind that most dolby headphone set-ups are limited to spdif/optical that I have run across while the MDR-DS7500s allow DTS-HD MA and DolbyTrueHD. Please note that there is no confirmation from Sony on what happens to the signal upon transmission to the headset even though it can RECEIVE and decode a lossless signal through the previous two formats or linear PCM (ie: capped at 48? instead of also transmitting the same true lossless signal it received).
From the Dolby Site:
With Dolby® Headphone technology, your customers will experience rich, dramatic surround sound over conventional headphones.
Delivers realistic 5.1-channel sound from any set of headphones
Provides a more comfortable listening experience, reducing listener fatigue
Enables superb surround sound from stereo music and movies when combined with Dolby Pro Logic® II
Dolby Headphone accurately creates the sensation of up to five loudspeakers in a room using powerful digital signal processing (DSP) technology. The result is a richer and more natural listening experience over conventional stereo headphones.
Dolby Headphone is compatible with native 5.1-channel content. When combined with Dolby Pro Logic II, Dolby Headphone can transform content from a two-channel source into a surround sound listening experience.
When reproducing a source that incorporates Dolby Pro Logic IIz preprocessing, Dolby Headphone provides a 7.1-channel surround sound experience.
Dolby Headphone electronically imparts the sonic signature of a corresponding speaker properly placed in a carefully defined acoustic environment to each audio channel (two on stereo programs, and up to five on surround programs). The subwoofer signal (the “.1” Low-Frequency Effects [LFE] channel) is mixed into the Left and Right channels in equal proportion.
All of this information is combined by the Dolby Headphone processor into two encoded channels that deliver the spatial properties of the original audio, with more natural sounds that actually seem to be “out-of-head.”
With Dolby Headphone technology, your customers will be able to enjoy a private listening experience over conventional headphones that delivers all of the excitement of realistic 5.1 surround sound.
Dolby Headphone is compatible with discrete 5.1-channel sources. When used together with Dolby Pro Logic II, it provides a surround sound listening experience from two-channel sources.
In addition, in conjunction with content preprocessed with Dolby Pro Logic IIz, Dolby Headphone can deliver a convincing 7.1-channel surround experience.
Dolby Headphone technology delivers surround sound through any pair of headphones. It can be included in almost any device that can process stereo or multichannel audio and has a headphone output.
The Dolby Headphone process can be embedded into DSP chips or implemented in software for use in home theater A/V receivers and preamp/processors, in digital TVs, and in PCs. Dolby Headphone also offers application-specific integrated circuit (ASIC) design for higher performance at less cost than a typical DSP solution.
From the outset Dolby Headphone technology was designed to encompass all possible audio formats. Conventional stereo, Dolby Surround, and 5.1-channel digital content can all be enhanced for headphone reproduction by the Dolby Headphone process. The result is a far more natural sound over any conventional wired or wireless stereo headset on all programs, from 5.1-channel DVDs to stereo MP3s.
Watched Starwars and HP7 for example on Blu-Ray and the positioning is very clear both in dolby digital and DTS HD MA mode. Things sound like they are beside you or around you. Of course I have yet to find a set of headphones that make something properly sound like they are behind you (only when compared to a full speaker 7.1 home theatre system). A light also turns on on the bottom of the box to indicate which decoding is being used.
AUTO OFF / ON FUNCTION
There is a master power switch on the left earcup. There is also the auto on/off feature that is built into the headband. Luckily there is no weighting or angle tilting sensor that turns them on or off or I would be going crazy haha. However, the headband looks like this.
. See how there is a second "strap/lining" on the inside of the headband that your head actually touches as you put on the headset (Quite comfortable by the way). This is actually/usually how the set turns on or off, however there is a master power switch on the earcup which you can turn off the headset and let your tv speaker kick back in. I would like to make sure you notice this as I bet some people will not like this (compared to an on-off switch on the side) or my senns which barely feel like I'm wearing them. So as you put the headset on the strap stretches and it pulls on the trigger in each earcup to turn on the headset. So if your wife needs to tell you something and you have to slide them off you could technically turn off the headset. The good news is that I think this is by design for power-saving purposes because the unit itself (the decoder box sitting across the room) continues to stay on and the stream is immediate the second you put them back on. So let's turn this to the "lying sideways" situation. I think Sony could have done a better job to make sure the headset doesn't turn off if say your shoulder pushes the edge of the earcup while lying sideways, but all in all it is pretty good. And your pillow will not put the pressure to turn off the headset that your shoulder can.
DSSS TECHNOLOGY (Sennheiser RS220s, Sonly MDR-DS7500, etc)
Here is a cut and paste but overall my buddy made sure that I got a headset with DSSS which is probably one of the reasons why this set sounds so good/clear. The Senn RS 220s were my next best choice. DSSS, as described by Sennheiser, "is a frequency spreading process in which the output signal is spread to a width of 22 MHz by means of a specified bit sequence." This means that the audio data is transmitted simultaneously on several different frequencies, so if one frequency experiences interference, the data is still able to get through on one or more others. Here is some more info on DSSS http://en.wikipedia.org/wiki/Direct-sequence_spread_spectrum.
SIGNAL STRENGTH AND DISTANCE TEST - TRYING TO CAREFULLY LISTEN AND WALK OUTSIDE LISTENING FOR MICRO DROPS AND INTERFERENCE
I have now had these for about 3 months as of March 31, 2012 and have used them thouroughly along with short doses of my buddy's RS220s. The signal is absolutely perfect even when I am downstairs and for reference I have 2.4ghz phones in the house, Wireless N internet, and my rear speakers downstairs on my receiver have a wireless transmitter which operates at 2.4 I believe. I tested the signal in detail about two weeks ago when I played a blu-ray on dts hd-ma and went from upstairs where I was watching the movie to downstairs in my basement and the signal was really strong. I was specifically looking for the micro-drops or drops that people on this forum were talking about with the rs220s. I then went to my front yard for a sec and it was still good. I think that was 30-50 feet distance at some points through drywall and wood framing in my house and no micro-drops, no drops at all. This has been a real awesome experience so far with this headset. I still find that I lean towards my Senn HD595 for the absolute best comfort in a wired solution and the HD600 650 700 800 obviously should be similar/better but for wireless I found the Sony's to be so much better than my buddy's RS220s. I may be biased since I think I like them better because they support hdmi and lossless transmission (note there may be some interpretation differences between losslesss input vs dsss output to the headset and I contacted Sony to get an answer if it actually transmits or downgrades to 16/48 when it transmits). If the Senns supported all the features and signal distance/strength of the sony and multiple headsets options of the Sony then I would likely have gone with the Senns due to the comfort and wider earcups and soundstage similar to my HD595.
This headset has a feature called compression which is just the reduction of the dynamic range peaks. I don't use it and prefer the non-compressed audio.
A/V Sync allows you to adjust the synch between the audio and video obviously hah. To access A/V Sync mode, hold the Compression button for 3 seconds or more. Then use the +/- Matrix and Effect buttons to adjust the audio delay. If you want to cancel this just press the input button.
LFE vs Center Channel
There are two buttons on the right earcup which allows you to change whether you hear more of the LFE channel vs more of the center channel. I prefer the default myself.
CHARGING AND BATTERY LIFE
I have charged these exactly 5 times in 3 months and use them for an hour or so at least a few times a week. Seems to last 15-18 hours or so of listening? Looks like the battery used is really holding up. Wish my cellphone would do the same!
Well hope this helps a bit as I think this may be the first detailed english review of this product. Now could someone who reviews a ton of wireless headsets also review these haha.
BOX DIMENSIONS (FOR SHIPPING PURPOSES)
Hi guys. Another head-fi-er asked about the dimensions of the box so they can calculate shipping. The dimensions of the cardboard box are:
Around 5lbs? Sorry no scale around me.
Here is a cut and paste of some further details in case it helps:
Another game changer from electronics giant Sony Japan comes the latest generation of wireless headphone with a newly developed chipset for 3D audio as well as Dolby NR professional Logic II z decoder supporting audio signals up to 7.1Ch. DMI inputs on the processor enables the new DS7500 to decode HD audio such as Dolby TrueHD. Also supports multi-channel linear PCM as well as Bravia HDMI CEC. Three HDMI inputs with 1 line HDMI output allows you to connect to your devices freely. Other improvement also comes with its support for 3D glasses, with a new flexible leather cushion that will not disturb you when watching 3D movies wearing both this Wireless Headphone as well as your mandatory 3D glasses.
Select from Sony's new "New Cinema mode" which is developed in cooperation with Sony Pictures Entertainment by analyzing the measured data for movie production in theaters. By combining with Sony's VPT technology this "New Cinema mode" "reproduces the sound of an ideal movie theater." In addition, a 2ch stereo voices under the "Voice mode" and "Game mode" are also available for optimized vocal and gaming reproduction.
The MDR-DS7500 weight 325g, has an 18h continuous battery life, a 5-25,000Hz reproduction bandwidth and support Dolby NR TrueHD, Dolby Digital plus, Dolby Digital, Dolby NR professional logic II z, Dolby NR professional logic. x, DTS-HD mastering audio, DTS-HD high-resolution audio, DTS 96/24, DTS-ES, DTS, Neo:6, MPEG-2 AAC, and linear PCM7.1ch/5.1ch
With up to 18 hours of continuous playback time the new DS7500 is one of the most advanced wireless headphone systems on the market.
Type: Sealed dynamic type
Driver unit: 50mm
Frequency Response: 5-25,000 Hz
Impedance: 24 Ω
Power: Built-in lithium ion battery
Battery life: 18 hours
Mass: About 325g
Processor / Transmitter: Controller DSSS
Effect Mode: OFF / Cinema / Game / Voice (Stereo)
Decoder: Dolby TrueHD, Dolby Digital Plus, Dolby Digital, Dolby Pro Logic IIx, DTS-HD Master Audio, DTS-HD High Resolution Audio, DTS 96/24, DTS-ES, DTS, DTS Neo: 6, MPEG-2 AAC, LPCM 2ch/5.1ch/7.1ch, Dolby Pro Logic IIz
Reach: Up to approximately 30m
Audio output: HDMI × 1, × 1 optical
Input terminal: HDMI × 3, × 1 rectangular light, stereo pin jack × 1
Mass: About 480g
Dimensions: (width × height × depth). Approximately 252 × 36 × 159mm
Power: Sony 100-240V AC Adapter
Incredibly Well-translated Great Grammar Google Translate:
新開発3D VPT(Virtualphones Technology)により従来の水平配置の7.1ch音場だけでなく、高さ/奥行き方向の音場を実現。 7.1ch sound field as well as the traditional horizontal placement, realized the sound field in the direction / depth by height (Virtualphones Technology) 3D VPT new development. 3D映像と合わせて映画など大迫力のコンテンツを楽しめます。 You can enjoy the content of such great power in conjunction with the video film 3D.
VPT（Virtualphones Technology） VPT (Virtualphones Technology)
映画館のような臨場感あふれるサラウンド音声を、ヘッドホンなどで手軽に楽しめるソニー独自のバーチャルサラウンド技術です。 Sony's proprietary technology is easy to enjoy virtual surround with headphones, etc., the immersive surround sound like the cinema.
デュアルDSPプロセッサー Dual DSP processor
DS7100で採用しているDSPを2セット使用することで、2倍の演算処理が可能となり、水平配置の7.1ch音場だけでなく、高さ方向と奥行き方向の音場を実現しました。 By using two sets of DSP has been adopted in the DS7100, two times the arithmetic processing becomes possible, as well as 7.1ch sound field of a horizontal arrangement, we have achieved a sound field in the depth direction and height direction.
Dolby PrologicⅡz対応 Support Dolby Prologic Ⅱ z
HDMI対応 HDMI support
高音質で楽しめるHD音声フォーマットに対応 Corresponds to enjoy high-quality HD audio formats
最大192kHz、24bit、非圧縮という、従来のDVDの約6倍以上の情報量を持つ高品位なソースにも対応。 Also supports high-quality source with more than six times the amount of information about 192kHz, 24bit maximum, called compression, non-traditional DVD. プロセッサーにHDMIの入力を3系統装備。
System equipped with three HDMI inputs to the processor. ブルーレイディスクレコーダー/プレーヤー、ゲーム機、衛星放送チューナー、ケーブルテレビチューナー等、最大3つの機器と接続しさまざまなコンテンツを高音質で楽しめます。 You can enjoy high-quality content in a variety of connected Blu-ray Disc recorder / players, game consoles, satellite tuner, such as cable TV tuner, and up to three devices.
オーディオリターンチャンネル（ARC） Audio Return Channel (ARC)
オーディオリターンチャンネル（ARC）に対応したテレビと本機プロセッサーをHDMIケーブルでつなぐと、テレビのデジタル音声信号が本機に転送されます。 When you connect an HDMI cable television and a processor unit that corresponds to the (ARC), a digital audio signal of TV will be transferred to the recorder audio return channel. 従来必要であった光デジタルケーブルを接続することなく、HDMIケーブル1本でテレビの音声を本機で楽しめます。 Without having to connect a digital optical cable was previously required, you can enjoy the TV sound on this unit at this 1 HDMI cable.
多彩なエフェクトを搭載 Equipped with a wide range of effects
「新」シネマモード Cinema mode "new"
ソニー・ピクチャーズ エンタテインメント（SPE）の協力のもと、その音質で定評のある映画製作用ダビングシアターの測定データを解析、ソニー独自のVPTとの組み合わせによる”理想的な映画館の音場”を再現しました。 The cooperation of the (SPE), analyzes the measured data of film dubbing theater for its quality-proven, reproduce the "ideal sound field of cinema" by Sony's unique combination of VPT and Sony Pictures Entertainment was.
ゲームモード Game mode
マルチチャンネルサラウンドのゲームを臨場感たっぷりに再生する「ゲームモード」を搭載。 Equipped with a "Game Mode" to play the game a lot of multi-channel surround presence. 株式会社ソニー・コンピュータエンタテインメントのサウンドデザイナー監修の正確な音場を実現します。 To achieve accurate sound field supervision of sound designer of Sony Computer Entertainment Inc..
ボイスモード Voice mode
2chステレオ環境下で人の声を聞き取りやすくします。 The easy to catch the voice of the people under 2ch stereo.
高級感のある皮張りハウジングと高伸縮イヤークッション Stretch leather ear cushions and a high sense of luxury housing
3Dメガネ対応 3D-compatible glasses
ラグジュアリーで高品位な質感と快適な装着感を両立。 Both the texture and comfortable feeling of wearing high-quality luxury. 3Dメガネ装着時にも低反撥イヤークッションが凹凸を包み込むように追従。 Wraps around the uneven follow-up as low-repulsion even when mounted ear cushions 3D glasses. 低音を逃さず、臨場感のある音を再現します。 Without missing a bass, and then reproduce the sound with more presence.
フリーアジャスト機構、オートパワーオン/オフ Freer adjustment mechanism, auto power on / off
調節不要のフリーアジャスト機構とヘッドホンを頭にかけるだけで自動的に電源が入り、はずすと自動的に電源が切れる、オートパワーオン/オフ機能。 The power will turn on automatically just put the headphones on your head and just mechanism of unnecessary regulation Freer, the power is turned off automatically when removed, auto power on / off. 手に取ってすぐに聞く体制になるスマートなヘッドホンです。 Headphone listening system is smart to be taken in hand immediately.
ヘッドホンにリモコン機能を搭載 Equipped with a remote control function to the headphone
ヘッドホンのハウジング部の操作部からセンターレベル／サブウーファーレベル調整、プロセッサーの電源操作、音場操作などの操作ができます。 You can adjust the level center / subwoofer level from the operation of the housing of the headphones, the operation of processor power, and some operations, such as sound field operation. 赤外線信号とは異なる無線信号を利用することで、離れた場所からでも、障害物があってもプロセッサーをコントロールすることが可能です。 By using radio signals and infrared signals are different, even from a remote location, to control the processor even if the obstacle is possible.
コンプレッション機能 Compression function
多彩なフォーマットに対応 Corresponding to a variety of formats
対応メディアフォーマット Media Format Support
Dolby TrueHD Dolby TrueHD
Dolby Digital Plus Dolby Digital Plus
Dolby Digital Dolby Digital
Dolby Pro LogicⅡz(＊) Dolby Pro Logic Ⅱ z (*)
Dolby Pro LogicⅡx Dolby Pro Logic Ⅱ x
DTS-HD Master Audio DTS-HD Master Audio
DTS-HD High Resolution DTS-HD High Resolution
DTS 96/24 DTS 96/24
DTS Neo:6 DTS Neo: 6
MPEG-2 AAC MPEG-2 AAC
リニアPCM 5.1ch/7.1ch Linear PCM 5.1ch/7.1ch
＊ Dolby Pro LogicⅡz機能は、ヘッドホンからのバーチャル再生にのみ対応しています Dolby Pro Logic Ⅱ z * feature is supported only from the headphone virtual reproduction
2.4GHz帯無線伝送式ヘッドホン 2.4GHz wireless headphone transmission formula
障害物を気にすることなく使用が可能なデジタル無線伝送方式ワイヤレスヘッドホン。 Wireless headphones digital radio transmission system that can be used without having to worry about the obstacles. 非圧縮伝送により劣化の少ない音質を実現します。 The sound quality with little degradation due to transmission of uncompressed.
※ 到達距離最大約30m ※ 30m reach a maximum of about
リアルタイムチャンネルセレクション Real-time channel selection
他の2.4GHz帯使用機器との干渉を防ぐ「リアルタイムチャンネルセレクション」を搭載。 Prevent interference with other 2.4GHz band devices and use the "real-time channel selection". 妨害電波を確認すると、自動で空きチャネルへと移動。 If you check the radio interference, and move to an available channel automatically. 音声が途切れることなく楽しめます。 You can enjoy without sound breaks off.
最大約18時間連続使用が可能 Can be used up to about 18 hours of continuous
約3時間のフル充電で 約18時間、約30分の急速充電で約3時間の連続使用が可能です。 About 3 hours of continuous use is possible with fast charging for about 18 hours, about 30 minutes on a full charge of about 3 hours.
※ 周囲の温度や使用状態により、上記の持続時間と異なる場合があります ※ depending on the condition of use the ambient temperature and duration may be different from the above
増設ヘッドホン対応 Headphone support expansion
別売りの専用ワイヤレスヘッドホン（MDR-RF7500）を増設することで、ワイヤレスの音声を複数の人で同時に楽しむことができます。 Is to increase the number (MDR-RF7500), you can enjoy at the same time more than one person dedicated audio wireless wireless headphones sold separately. 受信エリア内であれば、ワイヤレスヘッドホンを複数台使用できます。 If in the reception area, you can use multiple units of wireless headphones
7.1chサラウンドを複数人数で楽しめる増設用ワイヤレスステレオヘッドホン Wireless stereo headphones for expansion in the number of people enjoy 7.1ch surround more than one
Feel free to ask if I can help in any way with further info/vids.
George from Vancouver