It's a cell phone style speaker.... what did you expect? There is a thread on here on how to bypass the EZB4 speaker so you can amplify through an external amplifier.... Sorry I don't have the link at hand right now... There are contacts on the board to bypass the built in amp so you will have clean sound when you use your external amplifier...

@Richard R

First thanks for the reply

As far as expectations is concerned:

I didn't expect it to sound like my receiver and tower speakers but to be honest I did expect it to be on par or close to my cell phone speaker and frankly it's not even close, not due to volume but the static/white noise.

I am aware of the bypass and have seen the posts on it and it seems the way to go.

The goal of my post was:

1. To make sure something was not defective and that the output white noise was expected.
2. Assuming the white noise is expected then to see if anyone could assist in identifying an amplifier board with the criteria mentioned in my post since using a full receiver or large amp is not an option for me due to robot chassis size constraints.

Thanks

This little Stereo 2.8W Class D Audio Amplifier from Adafruit would probably work good for many robots

We tested with dozens of speakers and sound chamber designs. The speaker we chose is the most expensive and highest quality. The white noise, I'm unsure what you're referring too. However the quality of audio is determined by your input. If you are using the developers kit with the power base, I can recommend cutting a hole in the base where the speaker aligns from the ezb. The base will provide a chamber to amplify the audio.

The robots have holes in their bodies as a chamber for amplified audio, the power base does not.

Hi @Darathian,

It is normal to hear some white noise coming from the speaker while there is no audio being played as the onboard audio amplifier is always on and will pickup some electrical noise.

The white noise should go away when playing audio, but do keep in mind that you will hear less bass than you are used to as the audio is coming out of a cell phone speaker which is tuned for higher frequencies.

You could always upload a YouTube video of what you are hearing and we can compare.

Otherwise, we will look into this further and see if there is something we can improve on from our end.

I appreciate everyone's help.

I am using the EZB with the developers kit base.

I really don't expect bass from a small speaker.

Here is a video:

The sound file was played back using the EZB soundboard control for playback. It was taken at 60 on the slidebar.

It is on dropbox at Noise File

The hissing/white noise is audible in the video.

When using the SayEZB script command the white noise/hissing makes it so you cannot understand whats being said.

Thanks

I removed the EZB from the base and recorded the following at pretty high volume. It sounds way better but you still hear the hissing noise.

noise

I am not saying it's a bad speaker, in fact I am surprised how good it is actually... However, you can't expect surround sound Dolby stereo from it either.... If you need better sound do what Dave Schulpius did by bypassing the on board pre amp and running the clean output through an external amp....

Just a note, although the plastic shell acts like an awesome amplifier it can cause vibration where plastic parts vibrate against each other.... I fixed one of my EZB4 by adding a little bit of felt between the sides on the shell and the actual controller insert...

The audio file that is being played in the video sounds very low volume. I would recommend a normalized audio file that has been recorded at a higher volume. Also, if you are cranking the volume into "overdrive" (any volume value past 100), then the "clip" (in red) will flash on the sound board. Clip means the volume is too high and causing distortion. I would recommend researching what audio volume clip means for more information.

I have done a number of tests using a larger set of audio files at different recorded and control set volumes. The controll set volumes were between 60 and 80 volume level to prevent clipping. I used a combination of wav, mp3 and ring tones for a cell phone.

I have to agree it's not speaker quility. On some of the clips the audio is amazing.

Taking the EZB out of the base makes a huge difference on how audible the voice is rendered when the sayezb script command is used.

I will wait until I get my other parts to build six and see what difference the plastic channels DJ described makes.

Worse case I think i will use the bypass method since it may fit my use case better.

Can anyone confirm for me that the amp board wolfie suggested would work or if there is another board that would work better.

I truly appreciate all the help.

Thanks

I bypass the base and am very pleased with the quality of the audio on voices and mp3s

I have done some more testing.

I took the little board with mini deans connector our of the base and connected it directly to the EZB so I can do easy testing without the base.

It is a night and day difference with and without the developer kit base.

I will end up not using the base or mod the base based on DJ's recommendation.

One thing I did notice is that there is a very big difference in volume between using the soundboard and the sayezb command.

For the sayezb script command I need to set a volume level of 146 do get the sound clearly heard even without the base. I picked 146 since any higher causes clipping.

Does anyone have an idea what would cause the difference?

Thanks

The text to speech synthesis built into windows is a little lower volume, depending on the voice selected. The question of why Microsoft made their voices quiet may be a question for their forum if you ever stumble across it. We have many questions of why Microsoft does what they do

As for the audio volume with the power base, I recommend cutting a hole in the base that aligns with the speaker of the ezb v4. The robot bases each have a hole to use the body as an audio chamber. The power base does not have a hole. If you made one, it will be much louder.

@DJ

I have given up a long time ago on trying to make sense of the decisions Microsoft makes. The logic sometime boggles the mind.

In the short term I think what I will do is make a cable that will fit the deans connector on the EZB and do without the power base.

In the long term I will have to get the volume loud enough to be heard over the noise the servos make anyway and I think going the amp bypass way might be my best bet.

I really appreciate everyones input on this.