B&W Formation ~ Record Breaking Input Lag? ~

One of the striking claim I saw on B&W Formation Multiroom wireless speaker Suite is “1 microsecond synch between speakers in the same room.” This is unheard of and if true, definitely huge potential. Can this system allow previously impossible, super-low latency multi-room wireless audio setup such as for the use of DJ or for me Karaoke. I have received some clarifications from B&W.

What’s B&W Formation Suite

This is a multi-room wireless speaker ecosystem developed by legendary loud speaker maker, Bower’s and Wilkins. Currently, the suite consists of Flex (small bookshelf speaker), Wedge (single stereobox), Bar (soundbar), Duo (premium stereo speaker pairs), Bass (Bass unit) and Audio (passive system interface). Basically, one can consider these product as ultra premier version of Sonos.

Wireless all the way

One of design decision the company made for the formation line is similar to Sonos line that none of the formation speakers have wired input except Formation Bar. The Bar has optical input; other than that, one needs to spend $699.99 and buy Formation Audio to introduce Analog or Optical input to the Formation network. Even Sonos have product like Play 5 with Aux input.  For B&W’s defense, Formation speakers all have bluetooth Apt HD and Airplay 2. So Android users can stream pretty much anything from their phone/table at Hi-Res quality using Bluetooth. Apple users can stream CD quality via Airplay 2. On the contrary, Sonos have recently added Sonos Move, which is the only device with Bluetooth and that does not support even CD quality.

So technically, speaking B&W Formation line have almost full wireless connection support with exception of google chromecast support. Yet, many may still be concerned and bit hesitant to go all way wireless and ditch familiar wired technology entirely. I was one of them, but let’s think about when we actually need wired connection?

Most recent electronic devices have wireless connection interface especially bluetooth. One may want to add Alexa or Google Assistant capability. Since formation line do not have built-in support for these smart home assistant, one may consider hardwiring Amazon echo via Aux input if that was available. But even this circumstance, we can use bluetooth connection. Better yet, B&W announced upcoming addition of Alexa support soon. This is generally better connection than Aux connection anyways. For now, Google Assistant support is not listed though. The third case; however, is worth more attention. That is connection of other audio source such as turntable where there is no wireless connection.

B&W Formatin Audio

This is where Formation Audio ($699.99) comes into play. With Formation Audio, one can technically think as adding all those standard audio input to any of Formation speaker series. If we can assume price isn’t an issue here, there is another important consideration. Since it is not built in input to speaker(s), is input lag low enough? If not, Formation line have immaturely ditched wired connection as there is no true alternative to wired connection even one decided to pay (upgrade the system).

So let’s see what’s the input lag for formation system.

 

Input Lag Reference

The number may not mean anything if there is no reference. So let’s take a look at other market competitors.

Let’s use Sonos as an example. Sonos intentionally creates 70 ms delay even with directly connected SONOS Play 5 to audio source via Aux input (References: 1, 2, 3, 4).

The input lag was even worth with optical/TOSLINK on Sonos PlayBar with my own self-testing, which resulted 84-90 ms delay. The same test showed HEOS Bar from Denon had 77-81 ms delay. Even Bluesound Pulse 2 speaker with Aux input, I tried had audible delay but since It didn’t have Optical input, I could not test precise number.

Below is the table I created couple years ago when I was looking for low input lag/latency system alternative to Sonos PlayBar.

	HEOS Bar	HEOS 5	SONOS Playbar	Edifier S2000 Pro
From PS4 w/ Optical	77-81	N/A	84-90	41
From TV  w/ Optical	175	N/A	200+	86
From TV w/ AUX	90	90	N/A	88
From PS4 w/ HDMI	91	N/A	N/A	N/A

*Units are in milliseconds
** PS4 to TV using HDMI cable with TV built in speaker (set to Game mode) delay was 90ms

Are these delay noticeable?

70-80 ms sounds a very short time so does it really matter? If none of us can hear it, then it really doesn’t matter. So is 70-80 ms noticeable? The short answer is “yes”, pretty much anyone can here 70-80 ms lag. However, the catch here is most use case scenario, input timing is not clear; hence, lag may not be directly noticeable instead one may just think audio just don’t start right away.

Since there is buffering, after the first song, the initial lag may be only barely noticeable and rest won’t be perceivable. In these situations, 70 ms is short enough, most of us will feel instant play. In fact, Airplay buffering is longer.

Sometimes; however, these relatively short delay may become evident in situation like 5.1 surround sound TV speaker setup. One may notice audio is out of sync with movies. Though often video processing is more demanding, so these out-of-synch issue may be correctable by delaying audio or perhaps changing TV setup to reduce digital processing.

However, there are real situations where 70 ms delay becomes unacceptable and uncorrectable. These case scenarios are basically one has direct control of the input i.e. knows exactly when audio input is triggered. These cases include such as playing DJ Turntable, electric piano or in my case Karaoke. With these situations, 70 ms is absolutely perceivable and to the point, the lags are too much. Some may say Multiroom wireless speakers aren’t really built for these cases, but there are certainly some of us who think such feature may be nice.

With my personal experience with Karaoke, 70 ms lag was definitely noticeable with my voice out of synch from what was coming from speaker, and made Karaoke essentially undoable. With 41 ms delay achieved by Edifier S2000 Pro optical connection, the lag was unnoticeable. Of note, Edifier S2000 Pro is not a multi-room capable but good reference for number.

My current set up is Denon AVR with Bose passive speaker, which gives 60+ ms lag and it is acceptable delay but with fast paced songs, it is still noticeable.

Myth of 1 microsecond

Source: https://www.bowerswilkins.com/formation/flex

Formation suite claims in-room 1 microsecond sync between speakers. This may sound amazing compared to 40, 60 or 90 ms delays, but this is not the same delay we have been talking to this point.

Since I get entirely different numbers form B&W representative, I surmise 1 microsecond is “synch delay/lag/latency” rather than input lag/latency.

*1 millisecond (ms) is 1/1000 a second, and 1 microsecond is 1/1000 of 1 millisecond. 

Formation Series Input lag

So what is real input lag/latency on formation series?

Upon asking how much delay Formation Audio will have when connected to other Formation speaker, I have received following response from B&W representative.

The Formation audio’s optical input has a 2 ms local delay meaning that the input to output delay is only 2 ms for that source on that device.

If you were streaming that optical input to another Formation device setup to be in the same room then that delay would be about 40 ms while if you are trying to play from an Audio setup in one room to another player that is setup in a different room that would be no more than 100 ms delay.

So what does above statement mean? Well, I interpret above as following. Where ecosystem like Sonos introduce 70 ms delay locally, Formation Audio only introduce 2 ms.

Conceptually, we can/should think Formation Audio as an add-on input/output ports for Formation speakers (e.g. Wedge). In this unit, there is merely total of 40 ms delay when placed in the same room.

This is far better than SONOS Play 5, Playbar or HEOS Bar local direct connection. In fact, this number matches to the best number I got from Edifier S2000 Pro, which is again not a multi-room speaker.

Formation Bar

Even though above number was already impressive, I wanted to confirm such number even applies to Formation Bar with 5.1 set up. B&W rep response was following.

The optical connection on the Bar was designed to playback TV audio where a delay would be detrimental to the sync between picture and sound so in this case while there is a delay it is the sub 1ms standard. There is also no perceptible delay with regards to the audio being sent from the Bar to the Surrounds as they are again meant to be in time with the picture, the same is true for the Formation Bass when used with the Bar.

You will see the sub 1ms latency for room to room playback for normal playback of streaming audio as we can sync that content without possibly losing sync from the source as there is not 3rd party or outboard source.

Since I do not own Formation Bar nor Audio, I cannot test these on my own. However, if the above statement is true, B&W achieved previously impossible and perhaps premier title of Formation series may be even beyond/deeper than we think.