7.2 Ch. Sony Muteki STR-KM77 AV Receiver

From the 2012 STR-KM7 to the 2014 STR-KM77! The STR-KM77 is just an AV receiver for the HT-M77 component music system which in addition includes 9 speaker units. Sony has added attractive enhancements to the STR-KM7. One of my frustrations with the STR-KM7 was the absence of Bluetooth Streaming. Fortunately, it's like Sony heard my silent frustrations and introduced Bluetooth and NFC for Bluetooth pairing on the STR-KM77. This new feature now effortlessly allows you to stream directly from your compatible iPhone/iPod or smartphone to the STR-KM77. With the STR-KM7, I could only stream from my Android phone through a Bluetooth enabled Laptop

that is connected to the AV receiver via an HDMI connection. Thanks to Sony, my laptop is no longer needed!
Additionally, Sony has added more Soundfields on the STR-KM77. You can now enjoy your favorite football games with the Football sound mode active.

Attractive Features on the STR-KM77

• 2450W RMS Total Amp Output Power

Sony has boosted the power output on the STR-KM7 from 2012W to a staggering 2450W. If you like a home theater system with a heavy punch, this is cause for excitement. But wait, not just yet! Here is what I found out.
In stereo mode, it is rated at 120 W + 120 W (measured for 6 ohms, at 1 kHz and THD 1%) - which is the same with the STR-KM7. But when it comes to the surround mode, Sony has allowed the incredible to happen. The Amp channels are allowed to be driven into severe distortions by as much as 30% as indicated as follows; Measured for 6 ohms at 1 kHz and THD 30% to get 264W to FRONT speakers per channel, 266W to CENTER speaker, 264W to SURROUND speakers per channel, 264W to SURROUND BACK speakers per channel, and lastly measured for 4 ohms at 100 Hz and THD 30%, to get 300W to the SUBWOOFERS per channel.

To clearly understand this, you need to first understand the concept of THD explained here. But what this means is that in principle you will never fully enjoy Maximum volume on the STR-KM77 for a number of media sources as you will experience a lot more discomfort at these volumes than on the STR-KM7. However, realistically, ordinary usage is always at about half the rated maximum volume. And even at this level, it is loud enough for a large room. Unless you are hosting a party, maximum volume is never necessary!

• Bluetooth and NFC for effortless streaming

To me, this is the best addition that was lacking on the STR-KM7. You can stream directly from your compatible smartphone or tablet with a simple touch on the NFC area of the STR-KM77 receiver.

• Football and Digital Music Arena soundfields

Football and Digital Music Arena sound modes are a great addition, which were never present on the STR-KM7. You can now enjoy an enhanced football stadium atmosphere with the Football Sound field set to active while watching your games. In addition, the Digital Music Arena DSP brings Live Music Concerts to life as it mimics arena sound effects.

• 2 x 300 mm Metallic Cone type Subwoofer

Unlike the HT-M7 that is delivered with 2 x 250 mm metallic cone type subwoofers, the HT-M77 features slightly bigger subwoofer drivers of 300mm. This means, with the HT-M77 you enjoy a much heavier low frequency (bass) punch that will certainly rattle your windows and floor.

Full tech specs of the STR-KM77

• 2450W Total Power Output (Measured at 1kHz, 6Ohms, 10%THD)
• 7.2 analog Amplifier channels
• Falcon 2.0 DSP
• Speaker Terminal Color Socket 
• Bass/Treble Control
• Jog Input Selector 
• Bass and Treble Equalizer
• Speaker Level Control (dB) FRT: BAL. L+1 to BAL. L+6, BALANCE, BAL R+1 to BAL. R+6 CNT: +/-6 SL, SR: +/-6 SBRL, SBR: +/-6 SW: +/-6 

Inputs and Outputs

• Bluetooth(NFC) In
• 3 Audio In
• 2 Optical Digital In
• 1 Coaxial In
• 3 HDMI In
• 1 HDMI Out
• 1 USB In

Soundfields 

• Movie
• Music 
• Gaming 
• Football mode 
• Digital Music Arena

Decoding Formats 

• LPCM (2ch / 5.1ch / 7.1ch) through HDMI
• Dolby Digital
• DTS
• DTS 96/24 
• Dolby Prologic II
• 96k/24Bit PCM 
• Dolby Dual Mono 

Tuner

• 30 AM/FM preset channels
• Preset Channel FM/AM Station Name 
• Auto Tuning 
• Direct Tuning
• FM Mode

Video Features 

• A/V SYNC
• LPCM for HD Surround from Blu-ray Disc
• HDMI Quality - 1080p
• HDMI Quality - 1080/24p
• HDMI Quality - Deep Color
• HDMI Quality - x.v.Color (xvYCC)
• HDMI Quality - Audio Return Channel
• HDMI Quality - 3D Pass Through
• HDMI Quality - HDMI Pass Through
• HDMI Quality - 3D over HDMI

General Display 

• Union Jack Sleep Timer
• (up to 2 hours) Auto Standby 
• Pin Jack Nickel 

Speaker System 

• Subwoofer speaker system

• Bass Reflex Unit
• 300 mm cone type  driver.
• 4 ohms rated impedance 

• Front Speaker system

• Bass Reflex system
• 2 way 3 driver
• 25 mm horn type tweeter
• 2 x 200mm cone type Woofer
• 6 ohms rated impedance 

• Surround Speaker System 

• Bass Reflex unit
• 2 way 2 driver
• 25 mm horn type Tweeter
• 160 mm cone type Woofer
• 6 ohms rated impedance 

• Surround back speaker system

• Full range
• Closed Box Speaker unit
• 100 mm cone type woofer
• 6 ohms rated impedance

• Center Speaker System

• Bass Reflex
• Full range
• Magnetically shielded
• 6 ohms rated impedance
• 100 mm cone type woofer

Power requirements

• Input power: 110-127V or 220-240V AC, 50/60Hz depending on region.
• Power consumption in operation: 195W
• Power consumption in idle: 0.3W (with Ctrl HDMI set to off) 

Weight and Dimensions

• Main Unit (W x H x D): Approx 430 x 178 x 336mm Main Unit Weight (kg) Approx. 10.3kg 
• Front Speaker Size (W x H x D): Approx. 280 x 925 x 265mm Front Speaker Weight (kg) Approx. 15kg 
• Center Speaker Size (W x H x D): Approx. 430 x 182 x 178mm Center Speaker Weight (kg) Approx. 3.3kg 
• Surround Speaker Size (W x H x D): Approx. 280 x 885 x 265mm Surround Speaker Weight (kg) Approx. 13kg 
• Subwoofer Size (W x H x D): Approx. 410 x 555 x 350mm Subwoofer Weight (kg) Approx. 14kg
• Rear Surround Speaker Size (W x H x D): Approx. 280 x 235 x 162mm Rear Surround Speaker Weight (kg) Approx. 2.4kg 

 

Buying guide

• The HT-M77 currently goes for $1399.99 buying price, which is comparatively lower than other high end home theater systems in its category. I would bet that the HT-M77 is the best home theater you can get given its performance and at that price. 

•  Like its predecessor, the HT-M7, the quality of the media inputs affect performance of the HT-M77. So to enjoy it to the fullest always use high quality media sources, i.e HD movies, High quality audio, etc. 
• If you are to turn up the volume to maximum, set the speaker level controls at about 0dB. At this level sound distortions are less pronounced and the output is really good. Anything above 0dB makes the output sound uncomfortable to listen to.