Does wireless system degrade tone?

[Jim Comeaux]

Originally Posted by PeterM

Yikes...can of worms here...I know NOTHING about these devices, but here is some theory about as simply as I can put it.

Will wireless sound different? Most likely.

1. First the analog signal has to be digitized.
2. Then it has to be sent over the air to the receiver.
3. Then it has to be converted back to analog (most likely) to get to the speakers.

Each step involves processing and software etc. The quality of this software is VERY important here. Each time there is some software, there can (and likely will be) loss of data. Think early CD's...almost unlistenable compared to a vinyl record. Or think MP3's...again mostly unlistenable due to the compression used so that it would fit into the available bandwith.

So this partly could be a bandwith issue. Think cellphones...3G, then 4G, then 5G. Each generation has more usable bandwith. The more bandwith the more data can be sent over the air. Or partly software. Likely partly other things such as interference between the transmitter and receiver.

Think like this...when using a cable from your guitar, what is the quality of this cable? Why do they sell "good" "better" and "best" ?
Or think of bass players that use huge cables...that is to carry the bandwith required. Or some bass players use 2 cables...so that each individual cable carries only some of the signal.

In other words, lots going on right?

I am not a great guitarist, nor am I familiar with this particular electronic equipment, but I am a retired electronics engineer and I have many years of experience in digital and analog radio transmission from HF to microwave and IR. You misunderstand the challenges in transmission. You are correct in stating that there is some distortion in analog and digital transmissions an recordings. You are incorrect in how that distortion occurs. An analog signal, I.e. a sound wave is first converted into PAM, Pulse Amplitude Modulation. This is where in the process that they are talking about”sample rates. It’s too complicated to go into here but think of PAM as a hybrid of analog and digital signaling. The PAM signal is then further digitized into a pure digital signal of ones and zeros, or ons and offs or pluses and minuses, depending on the flavor of digitization being used. The reason that this is done is that a digital signal is perfect or very close to it all the way down to its crash point. In other words there is no degradation of the signal because it is weak. It is either perfect or near perfect or not there at all. An analog signal such as an AM or FM radio signal degrades slowly as its strength decreases. It is referred to as the signal to noise ratio. Every receiver has a noise floor. It’s that hissing sound you hear when in between channels.The ratio of the level of the analog signal above the noise floor is the S/N ratio. Think of it as listening to something in a noisy room as opposed to a quiet room. S/N ratio exists in digital transmission or recording as well, but it is irrelevant because the digital detector only counts ones and zeros not analog noise. So to put it as simply as possible, all of the distortion that is inherent in digital transmission or recording happens before it is transmitted and the distortion is perfectly replicated at the receiving end of the transmission until it is distorted again on the receiving end when it is reconverted to an analog signal.

Whew, O.K., I’m through with my diatribe.

[cmac]

I reckon there are maybe five potential sources of degradation with this kind of wireless unit, compared to one (capacitance) with cable. They are:

1. Analogue input path: The stage where the signal first arrives at the wireless link could have impedance issues, frequency colouring, and analogue noise. Generally, though, these are easily avoided.

2. Sampling distortion: The quality of an analogue to digital conversion depends on the quality of the converter hardware, but also the sample rate and the number of bits of resolution. 48KHz + 24 bits (pro-audio) is better than 44.1KHz + 16 bits (CD audio) which is better than 8KHz + 13 bits (GSM voice call).

3. RF interference / signal strength: The digital data is sent over the and in individual packets. If one of these is lost or corrupted due to interference or weak signal paths then the receiving end just has to interpolate / predict what the resulting audio waveform should look like. (There are redundancy and error correction algorithms, but these can only do so much in live audio.). Problems here will affect high frequencies more than low.

4. Digital to analogue conversion: The reverse of #2, the quality of the converter hardware makes a difference here. Also the DAC should be a very close match to the ADC.

5. Analogue output path: As with the input stage, all analogue circuits can impact impedance, tone and noise.

#3 is the biggie here. Good RF hardware and fast processing can push a higher bitrate over the air, with better redundancy and error checking. The 2.4GHz RF band is unregulated so there is a risk of congestion that, coupled with signal path challenges, means different people can have different experiences with the same wireless hardware.

Bottom line is that wireless links can sound as good as cable, but never better.

[Petty1818]

I wasn't a big fan of the Xvive system, but I have not noticed a tonal change with the Line 6 G10. I mean even adding more cabling to your board can alter tone so it depends on what your reference is. I think of it this way, can you fix it with slight eq? If so, it's not much an issue.

[MiniFlex2Mic]

I deeply appreciate the comments on this thread. Lots of good information. While I was originally a sceptic about the potential of wireless signal transmission, I am now a growing believer in the power of wireless signal transmission to reshape musical performances, and mostly for the better. Based on my experiences, most of the comments on this thread were accurate, but most were from a limited perspective. That is not a problem, as limited perspectives often go much further into detail than broad perspectives, and many such limited perspectives can create the most broad, and comprehensive perspective possible.

I have found that the most important element for a successful wireless setup is to have completely compatible equipment..... equipment which was manufactured in the same technology era, and with similar use of similar technologies. It is possible to mix different generations of technologies in a single signal chain, but this should be done carefully and cautiously. Creating any type of signal chain is an artistic exercise itself, and we must be cautious what pieces we use, how we arrange them, and how we adjust the controls for each piece of gear.

I am also finding that the wise use of newest generation digital gear creates new opportunities for recording and reproduction of sound at levels we never before experienced in a controlled setting. It is true that the audio signal is broken into 1's and 0's, but the quantity of 1's and 0's which can be processed by digital gear cumulatively equals or surpasses the capabilities of older and analog gear. It is a sound quality which I have come to call - SUPERNATURAL. And I use this term to mean that what we can experience with high quality digital gear used well takes us to a whole new level of sound which cannot be rightly compared to analog systems. They are simply apples and oranges - vanilla or chocolate. n

[AeroUSA]

I would say no system is as good or as reliable as a cable but some of the high end units are close enough. The budget options often add noise or lose highs in my experience.

[Methos1979]

This issue was just posited in a recent review of mine of a pickup system that I demo'd using a wireless system. Someone responded that perhaps a certain feature of tone (pick noise, clackiness) I talked about was due to my use of wireless vs. a cable. I've never really considered this an issue before but just for giggles I did an audio check of cable vs wireless and sure as heck the cable was more warm with less pick noise clackiness than the wireless. Far from an empirical test but I couldn't deny the difference.

[lkingston]

Your description makes it sound like the cable is degrading the sound more than the wireless, albeit maybe in a pleasant way.

[shufflebeat]

Originally Posted by Methos1979

This issue was just posited in a recent review of mine of a pickup system that I demo'd using a wireless system. Someone responded that perhaps a certain feature of tone (pick noise, clackiness) I talked about was due to my use of wireless vs. a cable. I've never really considered this an issue before but just for giggles I did an audio check of cable vs wireless and sure as heck the cable was more warm with less pick noise clackiness than the wireless. Far from an empirical test but I couldn't deny the difference.

Could the difference have been adjusted for at destination or source?

[shufflebeat]

Originally Posted by Jim Comeaux

...I am a retired electronics engineer and I have many years of experience in digital and analog radio transmission from HF to microwave and IR. You misunderstand the challenges in transmission.

...{reality according to the laws of physics}...

Whew, O.K., I’m through with my diatribe.

Much obliged for your input.

[Methos1979]

Originally Posted by shufflebeat

Could the difference have been adjusted for at destination or source?

The answer to that is yes. I did another test today and I was able to dial out the pick noise by dialing back the trebles a bit. The tone was warmer but you obviously also do lose some off the highs as well.

[roylor4]

I have been using a cheap Pac-rim wireless for about 3 years. I notice zero latency as long as I am close to the amp. There is a change in tone, but it is so negligible that you have to do an A/B test to hear it.

Mine now only stays charged for about an hour whereas it used to go for 3-4 easily. It has been a fantastic purchase and made my practices much more enjoyable not being tethered to anything physically. I will buy another, and FWIW, I will buy another $40 one. They sound fine. I have no experience with the nicer systems though and gig with cables.

[zeeway]

Did a gig today using cables, no wireless, and my sound was better - of course, this could also be a figment of my imagination, but for now, no wireless for me.

[dnf777]

Id have to say that most consumer grade wireless systems I tried have some signal degradation, but dont ask me to prove it. So I need to qualify that with “IMHO”

I bought a G-10 and liked the freedom, but kept jamming the transmitter into the couch pillows, and gave it up out of fear I would break a guitar side or jack.

[Marty C]

I use two different ones - one from Amazon for about $50.00 (had high ratings) and the other Xvive. The Xvive is better, but they both remove the warmth from my guitars. I can EQ some back in but still not the same as a good cable. It’s nice to be wireless and I keep bouncing back and forth between Freedom and tethered. Both have their advantages and disadvantages.

[Daniel Grenier]

I use a mid-level 5.8G and yes, my tone is better with a cable but not "better enough" to not use a wireless system. Cables out of a guitar really are a nuisance - especially if you tend to walk around when playing - and I am thankful to be able to get rid of it for a vey small price to pay in tone "degradation" (which, to me, is actually rather minor and somewhat fixable w/EQ).