Is S1 Pro Bluetooth quality worse than direct cable from iPad?

Portable PA
1

Hi

 

Is Bluetooth sound quality worse than direct cable from iPad to S1 Pro?

 

I thought that the iPad sends pure digital info via Bluetooth, and then it was the quality of the DAC converter in the S1 Pro that determined playback quality. ( Digital to Analog Converter)

 

Unless the DAC in the iPad is amazingly better than the S1 Pro? But then the 1/8" cable sending an analog signal would be slightly lossy.... Maybe sound guys mean reliability ( eg drop outs of Bluetooth signal ) not quality.

 

Let me know what you think, I need some expert advice before I open my big mouth.  : 0

 

 

Thanks !

2

Hello Paul,

 

I think the answer is "it depends" ... on your usage, audience, and source files.

 

For most performance characteristics, Bluetooth is perfectly adequate.  I found this great article covering Bluetooth Audio Codecs.  (It was written for headphone users but applies equally.)  I don't know which standard the S1 Pro uses offhand, but from the article it seems that even the lowest common denominator codec is still acceptable for all but the most critical audiophiles.  If you're outside or in a large area, you'll be competing with ambient noise and probably not perceive any difference.

 

The quality of the source material can make a difference as well.  MP3 files compressed at 64kbps can sound downright lousy, and some at 320kbps can sound superb.  If Bluetooth has to process an already-processed signal, you'll still experience some amount of loss, probably imperceptible, maybe not.  Are you playing for a critical audience in a controlled environment, or a dance party with rowdy patrons?

 

Regarding reliability, I think Bluetooth is a great convenience and lets me put audio where I want it when the reliability is not critical.  If I'm at home, especially out on the patio, Bluetooth is great.  If I'm performing professionally, whether indoors or out, I use a top-quality mixer and balanced cables wherever possible to ensure reliable delivery of any audio source I need to amplify and/or EQ.

 

Every person's needs are different, and your ear for sound quality as well as your tolerance for possible dropouts (and here's hoping you never have any) need to be your guides.

 

Does that help?

3

I did some tests.

 

We use the S1 Pro with mp3 256kbps drums and bass  backing tracks to complement acoustic instruments - for about 50 to 100 ppl in a "quiet" setting

 

My android phone sounds terrible with a direct cable connect, but sounds great with it's bluetooth. The iPad sounds great with cable or Bluetooth - especially the clarity and accuracy of low acoustic frequencies and ambience.

 

Is it correct to conclude that the DAC in the mobile phone is cheap, which explains why the cable connect is poor quality? But the poor DAC in the mobile phone is bypassed when transmitting the digital signal to the S1 Bluetooth receiver, and then the S1 Pro uses it's high quality DAC....??

 

Reminds of when high end stereo systems ( Denon, NAD ) boasted fibre optic input to use a DAC in the amp to get rid of weak analogue connections, or avoid low bit rate DAC's in cheaper CD players.

 

It would be nice to know for sure.

4

I don't have any specs or scientific evidence, but I do think your findings have merit.  When designing a phone, I think most manufacturers today would try to address the most popular selling points -- whether it's 5G speed, marvelous displays, Bluetooth transmission, etc.  I wonder what the figures are for the use of wired headphones these days?  So it seems reasonable that given a choice to design or license a great Bluetooth transmitter vs. a great DAC for wired connections, in today's market the transmitter would win.

 

I've had different people take videos of the same performance, and the audio quality captured by their phones varies widely.  I think that indicates that the recording analog-to-digital conversion (as well as the mic quality) varies a lot from phone to phone.  Seems to reason the digital-to-analog conversion could vary just as much.

 

 

5

Hi Paul6,

It'd be unusual for a mobile device's analogue output to be of much lower quality. I think instead it may be to do with the cable not seating correctly inside the phone's output jack. Is it possible your phone case is blocking the port?

6

Hi Dylan,

 

Yes, that has happened to me.... sometimes if the 1/8" stereo audio cable is not fully seated, then you can get a very thin tinny sound.

 

But after many audio tests, checking secure seating of the 1/8" plug, using different cables and different PA  Hi Fi systems, I found that some android mobile phones have relatively poor quality analogue output.. especially low frequency impact and clarity. So i am guessing the internal DAC is a small cheap chip on the mobile phone PCB board. Using the Bluetooth can get rid of this problem, as none of the phone's DAC is used.

 

The BOSE S1 pro is high enough quality for this to be noticed, and especially noticeable when teamed up with a BOSE Sub1 reproducing low end acoustic double bass backing tracks. To get the best out of the BOSE S1 Pro and Sub1, I found that high quality source input is critical. I either use the Bluetooth which uses the better DAC in the Bose S1 Pro, or make sure the cable input comes from a source that has a high quality DAC ... like an iPAD with a high end copper 1/8" audio cable.

 

Sure the difference is not huge, and you need to know what your listening for, but when BOSE engineers design an A grade product, it is a shame to let it down with a B grade source.

 

 

 

7

Hello again Paul6,

 

Your threads regarding Bluetooth, the S1 Pro, and Bose Subs have been interesting.  As so much new equipment and technology has come on the market, it is blurring the line between what has been referred to in the industry as "Pro level" equipment vs. "Consumer level" equipment.  I've seen this definition used a lot, especially by interface manufacturers, defining the connectors, signal levels, and "intended" uses.

 

By no means do I wish to imply that any of us are more "professional" or "consumer" than any others on this or any other forum.  As computers, tablets and phones have evolved, so has their quality and usability.  Personally, I would not use a phone as a music source except for "casual" use -- but that's just me.  I find them clunky to use because of their small size, my fat fingers, and my age -- but that's just me.  An iPad or tablet is bigger and better, and although I am not opposed to a touchscreen interface, I prefer the feel of knobs and faders when mixing audio -- but that's just me.  I prefer wired connections using XLR or 1/4" TRS interfaces -- but that's just me.  Your experience and ability is different -- not better or worse.

 

I do remember when I first started, I tried to use a home stereo and speakers to amplify my brand-new $49 bass guitar.  (Utter disaster, btw.)  Looking back over time, I realize how much I've learned going from a practice amp, to my first "stage-ready" amp, to a trailer full of equipment, and back down to Bose L1 systems and any number of venue-provided PA systems at outdoor festivals, auditoriums, and houses of worship.

 

Sorry for straying from the topic, but here's the reason:  I applaud that you see the progression in your future while leveraging the incredible "today" with the S1 Pro and Bluetooth technology.  I don't know whether Bose will be able to implement a switchable internal HPF that applies to only the internal speaker in firmware or not, and what timeframe that would involve. Neither do I know whether newer phones and tablets will implement better DACs.  I do know that the 1/8" "consumer level" cable jack in phones, iPads, laptops, an other "consumer level" devices tends to wear out quickly relative to 1/4" and XLR "Pro level" connections.

 

Ultimately, your next progression might be to a stereo Bluetooth receiver designed for "Pro level" connections, such as the XLR inputs on a Bose Sub1 or Sub2.  Switchcraft and On-Stage Stands (!) are two manufacturers that make XLR-based Bluetooth receivers that work in either mono or stereo (in case you add a second S1 Pro to your setup!)  They can be plugged into a mixer as well, if that is your next progression.

 

I think you have a great handle on your direction and great questions and suggestions!

8

Hi there,

 

Re; the pro level Bluetooth Stereo Receiver, there is one already available  - Radial Engineering BT-PRO V.2. Very well made, sturdy and what’s most important: great sound. Here’s the link to Sweetwater website: https://www.sweetwater.com/store/detail/BTProV2--radial-bt-pro-v2-2-channel-active-direct-box.

 

cheers,

Julian8023