The LG HBS-730 Bluetooth Headset Sucks Rocks

Nexus7-Headset-BT-xmitter verticalAs was mentioned a few weeks ago, I’ve been looking for a Bluetooth headset primarily for listening to music. This is a very different use case for me. For years I’ve reserved Bluetooth wireless devices exclusively for use with my mobile phone, making phone calls.

I bought one of the leading devices in this class, the LG HBS-730. It was recommended by several friends, so I thought it would surely be great. Except that it wasn’t. Compared to my reference, the Etymotic HF5, it sounded dull and lifeless when paired to anything I had on-hand.

This puzzled and frustrated me. So much so that I tried it with everything I could lay my hands on, including;

  • Nexus 4 mobile phone
  • Nexus 5 mobile phone (Stella’s)
  • Nexus 7 tablet
  • iPad 3 (Retina)
  • iPod Touch (4th generation)
  • iPod Touch (5th generation)

In every case the LG headset was disappointing. However, none of the devices I had on-hand were known to support the APT-X codec. ATP-X is an optional codec from CSR that is designed to deliver high-fidelity audio over Bluetooth.

Lacking for APT-X, the devices were falling back to the Bluetooth stand SBC codec, which can be implemented at various sampling rates and data rates. Some are suitable for music, but some serve only voice applications. I could understand that, having implemented the costly APT-X codec, their SBC implementation might be more baseline in nature.

Avantree Saturn BT transcieverThe situation vexed me such that I decided to purchase a Bluetooth transmitter known to support APT-X. I selected the Avantree Saturn Wireless Bluetooth Audio Receiver and Bluetooth Transmitter 2 in 1 adapter, with aptX. A device capable of acting as either transmitter or receiver, it would allow me to evaluate the LG headset in APT-X mode. It would also allow me to evaluate Bluetooth audio streaming from a mobile device to my reference headset, with perhaps a more capable SBC implementation.

When the BT transceiver arrived I gave it 30 minute to charge, set it to act as a transmitter, then tried to pair it to the HBS-730. It paired readily, so I plugged it into my Nexus 7 and tried to listen to some music streamed via the Amazon Prime applet. I also ensured that the equalizer setting in the tablet was both set to flat and disabled.

Sadly, the HBS-730 performed just as it had when paired directly to my Nexus 4…dull and lifeless. To my ears it sounded like it was rolled off above 8 KHz and perhaps below 100 Hz. That would be about the same performance as I would expect from something designed around TIA-920, the legacy specification that defines the audio channel for wideband telephony.

Next, I flipped the Saturn device into its receiver mode. I paired it to the Nexus 7 and plugged in my trusty HF5 wired headset. So, the signal path was BT from the tablet to the BT transceiver, then wired to the earpieces.

In this arrangement the combination sounded great! It was exactly what I had hoped for originally. I could finally hear the sizzle of the snare drum strikes and the high-hat cymbals!

The Nexus devices do not support the APT-X codec, that much is clear. However, their SBC implementation is more than adequate for music when mated with a BT receiver (or headset.) This also explains why the Nexus 4 sounds good when streaming music to our car stereo via Bluetooth.

Further, I expect that the Etymotic drivers are superior to those in the LG headset.

Next, I swapped the HF5 headset for my big ‘ole AKG K 240 Studio Headphones. These big head-huggers need a lot of drive, so the Saturn didn’t have quite the grunt necessary to deliver big volume. It did, however, sound perfectly acceptable. It didn’t exhibit any of the roll-off I was hearing with the LG headset.

My conclusion, as stated at the outset, is that the LG HBS-730 sucks rocks. That said, it’s not my way to ask you to simply believe when a I make such a statement. I’ll try to support the assertion with some evidence.

I thought that the best thing that I could offer would be a comparison of the output of the headset measured in a sensible fashion against a reference piece of music. Ideally, I’d create such recording using a binaural dummy head microphone….but I don’t have one of those. Even the cheapest I know of (3DIO Free Space Pro – Binaural Microphone) costs $499, more than I can justify for this kind of effort.

Since I’m not planning on using the HBS-730 I decided to simply cut off one of the earpieces, adapting the raw wire end to connect to an audio recorder. This isn’t as good as a dummy head since it circumvents the impact of the earpiece driver. It primarily allows me to capture the performance of the electronics.

I made two recordings. In both cases the music is one of my favorite songs played from Amazon’s Online music app on the Nexus 7. The first recording is made from the analog output of the Avantree device acting as a Bluetooth BT receiver. The second recording is the very same song, but recorded by hardwiring one of the earbud feeds into the same flash recorder.

BT comparison Small

I normalized each recording to ensure that the levels matched. I didn’t bother to trim them to exactly the same length. Finally, I turned on a spectral display hoping to see a clear difference between the two recordings. Except, as you can see, the differences were slight, which was a surprise to me.

To my ears, the differences between the HBS-730 and the Avantree Saturn + HF5 combination are both profound and obvious. That leads me to believe that the difference that I hear stems from the drivers on the LG HBS-730. It may have little or nothing to do with the Bluetooth link at all.

I understand the Brian West has one of the 3DIO binaural microphones. Presumably it’s a research tool used in the implementation of the stereo aspect of the Freeswitch Verto Project. I wonder if he’d be willing to lend it? Nah, probably not. I probably shouldn’t obsess in such a pubic fashion.

You may be wondering why I’ve put so much effort into this matter. Well, when things disappoint that provides motivation. Also, the 3.5mm jack on my 18 month old Nexus 4 ceased to work about a month ago. Thus I am compelled to use Bluetooth to use any kind of headset with that device. I’m planning to upgrade my cell phone in the coming months, but awaiting the launch of the next in Google’s Nexus series.

For the moment I’m using the Nexus 4, with the Saturn BT receiver connected to the Etymotic HF5 headset. That combination is more than satisfactory, if not entirely wireless.