Hidden stereo amp
Discussion
I want to put a radio in my MG, but want to hide it in the boot and just stream spotify to it by bluetooth.
Loads of stuff on ebay that should in theory do the job, but ive no idea how well it would work in practice when subject to dirty power and other interference in the car. So wondered if anyone had done similar and had any recomendations?
Not fussed about things like subs, just needs enough power to be heard over the noise of the engine/wind. I suppose the easiest option would be to just fit any old stereo in the boot and a bt->fm transmitter in the cigarette lighter socket.
Budget is tight otherwise id just buy a new stereo, but as im not going to use 90% of its features i figured there might be money to be saved.
Loads of stuff on ebay that should in theory do the job, but ive no idea how well it would work in practice when subject to dirty power and other interference in the car. So wondered if anyone had done similar and had any recomendations?
Not fussed about things like subs, just needs enough power to be heard over the noise of the engine/wind. I suppose the easiest option would be to just fit any old stereo in the boot and a bt->fm transmitter in the cigarette lighter socket.
Budget is tight otherwise id just buy a new stereo, but as im not going to use 90% of its features i figured there might be money to be saved.
thisisnotaspoon said:
I want to put a radio in my MG, but want to hide it in the boot and just stream spotify to it by bluetooth.
Loads of stuff on ebay that should in theory do the job, but ive no idea how well it would work in practice when subject to dirty power and other interference in the car. So wondered if anyone had done similar and had any recomendations?
Not fussed about things like subs, just needs enough power to be heard over the noise of the engine/wind. I suppose the easiest option would be to just fit any old stereo in the boot and a bt->fm transmitter in the cigarette lighter socket.
Budget is tight otherwise id just buy a new stereo, but as im not going to use 90% of its features i figured there might be money to be saved.
While it's not QUITE the answer you want, my solution for aux-in might apply here.Loads of stuff on ebay that should in theory do the job, but ive no idea how well it would work in practice when subject to dirty power and other interference in the car. So wondered if anyone had done similar and had any recomendations?
Not fussed about things like subs, just needs enough power to be heard over the noise of the engine/wind. I suppose the easiest option would be to just fit any old stereo in the boot and a bt->fm transmitter in the cigarette lighter socket.
Budget is tight otherwise id just buy a new stereo, but as im not going to use 90% of its features i figured there might be money to be saved.
On my past two cars they've had a 3.5mm aux input, so I jumped on ebay and bought a bluetooth receiver which had a 3.5mm output. Cost about a tenner. Powered by a micro-USB cable.
So my suggestion is: Get a head unit that's got a 3.5mm aux input; secondhand will do just fine, then get a bluetooth to 3.5mm receiver. If the head unit has a USB socket on it then you can get the power from there.
Shouldn't cost much & will mean you're using a standard car stereo so it'll cope with the voltages and electrical noise.
Use one like this if you are just using spotify/phone
https://www.amazon.co.uk/Nobsound-Bluetooth-Amplif...
Small enough to hide under the dash
https://www.amazon.co.uk/Nobsound-Bluetooth-Amplif...
Small enough to hide under the dash
[Quote]Shouldn't cost much & will mean you're using a standard car stereo so it'll cope with the voltages and electrical noise.
[/quote]
I thought that, but you can pick up a BT car stereo for peanuts on ebay, less than a dongle!. Just seems like a bit of a faff if a little box existed that did it all without wires everywhere getting snagged and knocked about.
[/quote]
I thought that, but you can pick up a BT car stereo for peanuts on ebay, less than a dongle!. Just seems like a bit of a faff if a little box existed that did it all without wires everywhere getting snagged and knocked about.
So I bought the nobsound, here's a bit of a review before it gets wired into the car.
Its quite quiet when fed 12v from a battery.
So I bought a 12-24V power supply. This type of amplifier cant produce a voltage higher than the input so at 12v it was limited to 12v/4ohms = 3A, or 36W. 24v makes that 142W, much more like it 😈
Next problem, the nobsound. Put politely its horrible quality sound. With no load on it you can hear the static reach a peak at about 2/3 volume then actually get better as you turn it to max! With a phone connected via BT and wired upto some sony 6x9 its pretty terrible. Hard to describe whats wrong with the sound other than it sounds like youre playing music through the cheapest amplifier you could get on amazon, which you are.
But its going in a car, so for the most part who cares? And being a class B type amplifier at least its efficient and generates no noticeable heat eaven when left to its own devices in the shed for a few hours to test it ( sorry neighbours) . Worst case I cant live with it and we go back to plan b, a secondhand stereo hidden in the boot.
Next step is to get it into the car. Ive got the original center console and pulled out the birds nest and old radio. Plan is to wrap it in carpet to cover the old holes and just leave the nobsouns nob protruding through a suitably sized hole. Speakers can just go in holes in the parcel shelf, leaves room to stow the hood then and the alternative is taking the wings off to fit them in the footwell and that doesnt really appeal.
Its quite quiet when fed 12v from a battery.
So I bought a 12-24V power supply. This type of amplifier cant produce a voltage higher than the input so at 12v it was limited to 12v/4ohms = 3A, or 36W. 24v makes that 142W, much more like it 😈
Next problem, the nobsound. Put politely its horrible quality sound. With no load on it you can hear the static reach a peak at about 2/3 volume then actually get better as you turn it to max! With a phone connected via BT and wired upto some sony 6x9 its pretty terrible. Hard to describe whats wrong with the sound other than it sounds like youre playing music through the cheapest amplifier you could get on amazon, which you are.
But its going in a car, so for the most part who cares? And being a class B type amplifier at least its efficient and generates no noticeable heat eaven when left to its own devices in the shed for a few hours to test it ( sorry neighbours) . Worst case I cant live with it and we go back to plan b, a secondhand stereo hidden in the boot.
Next step is to get it into the car. Ive got the original center console and pulled out the birds nest and old radio. Plan is to wrap it in carpet to cover the old holes and just leave the nobsouns nob protruding through a suitably sized hole. Speakers can just go in holes in the parcel shelf, leaves room to stow the hood then and the alternative is taking the wings off to fit them in the footwell and that doesnt really appeal.
Bit of an update
It's (mostly, I need to screw the console to the trim) in!
The sound from the nobsoud is horribly thin, I actually wonder if the design has got the phase the wrong way round somewhere. To counter that I downloaded an app called Neutralizer to my (android) phone. This plays a series of tones and you adjust the volume until they're on the threshold of audible to get a neutral EQ for your hi-fi/headphones. It now works really well although as I was adding 2-3db of gain to the lower frequencies it results in a quieter overall sound as presumably it can only ever lower the signal (you can't add 3db to one range, but you can take 3db off everything else). It now sounds pretty good, it's not Hi-Fi or expensive headphone quality, but good (and loud) enough.
I've installed it with a polished chrome 2-gang blanking plate over the original holes in the console, with holes drilled for the potentiometer stalk and wires/mountings for the interior light.
The whole thing is fed by 14awg wire from the battery and a 15A fuse, a relay fed from the ignition switch turns the stereo on when the ignition is on but means the light can be switched on even without the key, I fitted an LED bulb so no danger of draining the battery.
The Nobsound uses a DC plug that didn't come with it, and I didn't like the idea of connectors that could rattle loose, so I dismantled it and soldered some wire tails to the board and spliced these to the tails from the 12/24 PSU. At this point, I could have left the board out of its casing to allow better cooling and just double-sided taped it behind the console, but opted to put it back in the case to reduce the risk of flapping wires shorting anything on the 24V side (which is only protected by the fuse on the 12V side).
Overall I'm really happy with it.
I might keep an eye out for a proper power amplifier with remote volume control that can be mounted in the boot to upgrade it but the only ones I can find are designed to be fed from a head unit. The other option would be to find an alternative BT receiver to the nobsound with volume control but no amplifier, then just run a line to a better amp in the boot.
Pics to follow once I've tidied up!
It's (mostly, I need to screw the console to the trim) in!
The sound from the nobsoud is horribly thin, I actually wonder if the design has got the phase the wrong way round somewhere. To counter that I downloaded an app called Neutralizer to my (android) phone. This plays a series of tones and you adjust the volume until they're on the threshold of audible to get a neutral EQ for your hi-fi/headphones. It now works really well although as I was adding 2-3db of gain to the lower frequencies it results in a quieter overall sound as presumably it can only ever lower the signal (you can't add 3db to one range, but you can take 3db off everything else). It now sounds pretty good, it's not Hi-Fi or expensive headphone quality, but good (and loud) enough.
I've installed it with a polished chrome 2-gang blanking plate over the original holes in the console, with holes drilled for the potentiometer stalk and wires/mountings for the interior light.
The whole thing is fed by 14awg wire from the battery and a 15A fuse, a relay fed from the ignition switch turns the stereo on when the ignition is on but means the light can be switched on even without the key, I fitted an LED bulb so no danger of draining the battery.
The Nobsound uses a DC plug that didn't come with it, and I didn't like the idea of connectors that could rattle loose, so I dismantled it and soldered some wire tails to the board and spliced these to the tails from the 12/24 PSU. At this point, I could have left the board out of its casing to allow better cooling and just double-sided taped it behind the console, but opted to put it back in the case to reduce the risk of flapping wires shorting anything on the 24V side (which is only protected by the fuse on the 12V side).
Overall I'm really happy with it.
I might keep an eye out for a proper power amplifier with remote volume control that can be mounted in the boot to upgrade it but the only ones I can find are designed to be fed from a head unit. The other option would be to find an alternative BT receiver to the nobsound with volume control but no amplifier, then just run a line to a better amp in the boot.
Pics to follow once I've tidied up!
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