No sound from Preamp

[Azulan]

Hello!

I got a new receiver (denon AVR 2312) and preamp Cambridge Audio 540P yesterday but i cant get sound out of my turntable and i have no idea if the problem lies in the preamp, receivers input or just sound settings on the receiver. I have the preamps output connected to the CD input on the receiver. Otherwise the receiver plays music great with ARC hdmi.

I dont know how to test the receivers inputs since i dont own a cd or dvd player.
Rest of my parts are in my signature.

Any help and tips would be appreciated.

 

[Azulan]

Hello!

I got a new receiver (denon AVR 2312) and preamp Cambridge Audio 540P yesterday but i cant get sound out of my turntable and i have no idea if the problem lies in the preamp, receivers input or just sound settings on the receiver. I have the preamps output connected to the CD input on the receiver. Otherwise the receiver plays music great with ARC hdmi.

I dont know how to test the receivers inputs since i dont own a cd or dvd player.
Rest of my parts are in my signature.

Any help and tips would be appreciated.

Forgot to mention. I am not sure the power cord for the preamp is original. there's no brand name on it but the light lights up

 

[GSV Ethics Gradient]

Is there no sound, or is it just very quiet?

 

[Azulan]

Is there no sound, or is it just very quiet?

no sound at all. exept hissing when i turn the volume up high

 

[Al ears]

Was the 540P sold as working?
What turntable are you connecting?
Have you tried any of the other inputs on the AVR?

 

[Azulan]

Was the 540P sold as working?
What turntable are you connecting?

yes it was sold as working. turntable is Technics sl qd33. i also just tried connecting my phone with aux to rca to the reciever. also no sound

 

[Azulan]

yes it was sold as working. turntable is Technics sl qd33. i also just tried connecting my phone with aux to rca to the reciever. also no sound

it seems to work when connecting my pc. but theres ALOT of humming

 

[Azulan]

Update. My tech savvy friend came over to take a look. it's most likely the preamp. Even though the preamp seems to be working properly when checking with a multimeter it just doesnt do its job. he took a look inside and one part is swollen and about to blow.

 

[Al ears]

Update. My tech savvy friend came over to take a look. it's most likely the preamp. Even though the preamp seems to be working properly when checking with a multimeter it just doesnt do its job. he took a look inside and one part is swollen and about to blow.

Doesn't explain why your phone wouldn't work either when connected to the amp.
Get your savvy friend to connect something like a cd player and try that.
It's still possibly an issue with settings on the amp itself.

 

[Azulan]

Doesn't explain why your phone wouldn't work either when connected to the amp.
Get your savvy friend to connect something like a cd player and try that.
It's still possibly an issue with settings on the amp itself.

will do

 

[Azulan]

Doesn't explain why your phone wouldn't work either when connected to the amp.
Get your savvy friend to connect something like a cd player and try that.
It's still possibly an issue with settings on the amp itself.

i figured i could plug my piano into the reciever and that also works fine.

 

[Azulan]

i figured i could plug my piano into the reciever and that also works fine.

i think i proved it's the preamp now. i connected the turntable straight into the receiver and i got sound it was weak as you'd expect without a preamp but at least there was sound. when i had the preamp connected there was no sound whatsoever.

 

[Gray]

I am not sure the power cord for the preamp is original.

That's important.
I own a 540P, so I've just checked.
The original, correct power supply is 12volts A.C. 500mA.
Get your mate with the meter to check that whatever PSU you've got, is giving out 12 v AC.
(His first reaction might be to set his meter to DC volts - he should be looking for AC volts).

If he gets a DC volts reading, your PSU is not the original.

 

[Azulan]

That's important.
I own a 540P, so I've just checked.
The original, correct power supply is 12volts A.C. 500mA.
Get your mate with the meter to check that whatever PSU you've got, is giving out 12 v AC.
(His first reaction might be to set his meter to DC volts - he should be looking for AC volts).

If he gets a DC volts reading, your PSU is not the original.

 

[Azulan]

i will bring it tomorrow to him. in the meantime that's the psu. it's 12V. not sure if AC or DC tho

 

[Gray]

i will bring it tomorrow to him. in the meantime that's the psu. it's 12V. not sure if AC or DC tho

That one is DC and capable of giving out up to 3 Amps - which means that someone gave you a more expensive one than they needed to 🤪
Importantly though, it should have done no harm.
But if someone is careless enough to lose the original....who knows what they might have powered it with before you got it?

 

[Azulan]

That one is DC and capable of giving out up to 3 Amps - which means that someone gave you a more expensive one than they needed to 🤪
Importantly though, it should have done no harm.
But if someone is careless enough to lose the original....who knows what they might have powered it with before you got it?

true that. i'm just glad my reciever seems ok. only paid 10€ for the preamp

 

[Roger_A]

i will bring it tomorrow to him. in the meantime that's the psu. it's 12V. not sure if AC or DC tho

The label you posted shows 12V DC. There are supplies on eBay that claim to be either genuine or equivalent supplies for your preamp. If it was sold as working then the seller wasn't being honest as it wouldn't work with the PSU provided. I just hope you haven't damaged it by connecting it to a DC supply.

 

[Gray]

true that. i'm just glad my reciever seems ok. only paid 10€ for the preamp

I fear that the seller may have known the Cambridge was defective - then just bunged you any old power supply - as long as it lit the blue LED.

 

[Azulan]

I fear that the seller may have known the Cambridge was defective - then just bunged you any old power supply - as long as it lit the blue LED.

yeah i agree. seems odd though. he's in his late 50s, lives in a nice house in the better part of the city. he obviously has money.

 

[Gray]

yeah i agree. seems odd though. he's in his late 50s, lives in a nice house in the better part of the city. he obviously has money.

Did you get the Denon from the same seller?
Have you proved that to be ok?

You shouldn't be having to repair the 540P - best option is to get your money back.

However, as your mate has already opened it, here's a photo of how the power supply should look:

Tell him that, when given the correct 12v AC power supply, he should be measuring +18v DC and -18v DC out of the two regulators U1 & U2 (bolted top) with respect to the ground post.

 

[Azulan]

Did you get the Denon from the same seller?
Have you proved that to be ok?

You shouldn't be having to repair the 540P - best option is to get your money back.

However, as your mate has already opened it, here's a photo of how the power supply should look:
View attachment 7847
Tell him that, when given the correct 12v AC power supply, he should be measuring +18v DC and -18v DC out of the two regulators U1 & U2 (bolted top) with respect to the ground post.

yes the denon seems fine in every way. there's loud humming when i have my pc connected but only on my pc. when i have my piano connected there's no humm and playing musik with chromecast to the reciever there's no humm. neither did the turntable cause any humm. so i think the humming is cause by my pc. Also watching TV there's no humm. That part i circeled in red is swollen on mine. i already got a new one for 1€

 

[Gray]

That part i circeled in red is swollen on mine. i already got a new one for 1€

Good.
Make sure to get the correct polarity when soldering it in.
Then get your mate to check those regulator outputs with 12v AC in.

With any luck, for 11 Euros plus the price of a correct power supply, you might have a working preamp 👍

 

[Azulan]

Good.
Make sure to get the correct polarity when soldering it in.
Then get your mate to check those regulator outputs with 12v AC in.

With any luck, for 11 Euros plus the price of a correct power supply, you might have a working preamp 👍

Will do. Went to my mom's place to scavange her cable monster and found this.