Hi one and all from the UK.

This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Hi there.
I'm hoping some one out there can help me.
I'm unsure whare to post this so have started here.
Appologies for the length of this.

For my sins I work for a Telematics company and repair their SatNav products. We are moving premises into a quiet office so need to reduce our audio test noise. We manually test the audio output at a high level by geting the satnav to talk to us. Hardly scientific, but it does the job.

My question is this, how can I reduce the volume without reducing the stress put onto the audio circuit. My boss has suggested bluetooth headphones from the speaker output socket, but i have my reservations about that, and I'm not keen on wearing them all day. I was wondering if I could load the audio circuit correctly but monitor the signal with something, like a scope or PC based item. I beleive in keeping things simple as I will have to maitain it but am open to any ideas.

The amplifier is a TPA3001D1 monal IC from TI, capable of 20w, but our speaker is rated at 10W max and doesnt exhibit any distortion at full volume.

So, not a very exciting question but I look forward to any suggestions offered.

Thanking you in advance!
Just another Moderator
Joined 2003
Paid Member
Hi Dinky and welcome to diyAudio.

I'm not sure where the best forum for this question would be. I think that a dummy load seems like an appropriate solution. Do you need to be able to hear the output? a purely resistive load won't fully emulate a speaker, but a dummy load with reactive components could probably be made.

Hi Wintermute,
Thank you for the welcome.

I am erring on the side of a dummy load. I dont have the faintest idea where to start with making one of those, so was wondering if I could use a modified speaker. If most of the speaker diaphram was removed, the electrical characteristics would remain the same but make little or no sound. The remaining paper would need stiffening to offer the same mechanical resistance.

As to monitering the output I thought a VU meter might do the trick, either analogue or digital. We have one scope that we share so thats not a realistic option due to cost. I would also have a speaker that can be switched in and out for live listening.

I will investigate the VU andhave a crack at the speaker next week and let you know how I get on.

Thanks again for your reply.
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.