I have a STR DE315 receiver and hear no sound from the speaker outputs yet all other functioins work and the headphone output works too. is it possible the speaker outputs need replacing?

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https://www.sony.com/electronics/support/audio-components-receivers-amplifiers/str-dg800

I'd suggest you concentrate your search around the power output.

Check that the mute is not on.If a headphone is plugged into the receiver the speakers will be muted.Verify the the output selector is set to the correct source.Here is a simple check.Select a strong FM radio station.Plug in a headphone.If you are receiving an audio thru the headset.Then disconnect the headset and see if the audio is transmitted to the speakers.If you still have no speaker sound check to see if the speakers have fuses which may be blown.I would try another set of speakers to determine if it's the amplifer or the speakers.The amplifer has fuses as well. Wiilbe inside if not at the rear

Headphone jack is an output not input jack. Your going to need a cord to go from your headphone jack(output) of your phone to audio input on your receiver. The cord has a mini stereo plug to the phone and RCA plugs of left and right to your receiver auxiliary input. Good luck..

There's really not enough info here to answer your question. What outputs are you connecting to what inputs on your receiver? 1. Does the receiver produce sound from other inputs? If yes, then receiver to speaker is OK. 2. Do you have sound at a headphone jack but not speakers? This would indicate bad speaker wiring or blown output fuses.
A bit more info will help - maybe gathering it will lead you to where the connection is not correct.

discharge the output circuit! If you don't you will blow a 10 ohm resistor every time. I've worked on hundreds of these receivers I know. They need the output circuit soldered at the voltage driver ic's and quite possibly some capicitors replaced on the digital board. The caps mounted near the heat sinks dry up the fastest. These are nice amps. Larry's Electronics Sacramento Ca. [email protected]

It would depend a lot on what type of subwoofer you have and it wouldn't be pretty.

According to the manual I found it doesn't have a Woofer Output so it isn't designed to route Low Frequencies anywhere.

Even if you rigged an Active Subwoofer to it using the Tape Output you wouldn't have central volume control for it unless the (unnamed) Sub was driven by speaker-level outputs from the Front A or B Speaker posts on the receiver.

Your question would be better framed and answered if we knew the details of the Sub and referred to ITS manual.

Does it still do this if the speaker wires are disconnected? The amp is protecting itself from a short on the output. maybe yo have a dead or distorted driver in one of the speakers. Also there could be a defect in on of the amp circuits.

Sounds like the output stage is shot.
Here are a few things to try. If there is an option in the manual to reset the unit to factory settings, try that.
If that doesn't work, disconnect all of the peripherals, and select the radio. If you get sound there, you may have a bad cable.

Beyond that I would say the amp needs repaired.

Cheeres

I have experienced a similar problem with my Sony STR-GX57ES and took it to a certified tech only to find it needed the power supply replaced. I opted to hunt down a compatible power supply but have been unsucessful thus far. That being said I picked up an STR-D665 for next to nothing and found the power supplies to be quite different (you would hope so any, with the ES meaning Elivated Standard and all) but with the D665 working flawlessly I'd rather have something working than nothing. Good luck!