Help fixing a Wharfedale amplifier

Thread Starter

donny0m

Joined Oct 19, 2022
12
Bought this amp and speaker set at a garage sale, owner said speaker dont work. I've tried out the speakers and they are great. Turns out the active subwoofer does not output signal to the speakers. The sub woofer speaker itself is going though.

I opened up the back plate to see if there was a fuse out. Only found two 6.3A fuses both intact, makes sense now because the sub is firing. There isn't any apparent damage to the circuitry and cant figure out why the speaker outputs are busted.

Any ideas on how you'd go about troubleshooting this? I have a basic understanding of electronics and have tools/multi-meter/soldering iron, etc.

IMG_3891.jpgIMG_3888.jpgIMG_3889.jpgIMG_3890 - 01.jpg
 

WBahn

Joined Mar 31, 2012
27,903
How old is this thing? One thing to look at are the electrolytic caps, especially the bigger ones. Look for signs of venting or leaking.
 

Ian0

Joined Aug 7, 2020
6,713
I'm not sure how old it is. Some google searches on the model number suggest could unto 20 years. Yea the leakage there doesn't look good. I could replace them and give it a test. Might be worth a try you reckon?
Looks like glue to me.

Fane took over Wharfedale in the 1990s, and released products which were more PA than hi-if, reasonable quality, Chinese made.

It looks like there is a speaker protection relay. Is that relay switching on?
If not, is there a DC level on the output of the power amplifier going into the relay. If so, you probably have a faulty output transistor (or two). Usually that would blow the fuse.

If the relay switches on, is there any output hiss or is it completely silent?
 

Thread Starter

donny0m

Joined Oct 19, 2022
12
Looks like glue to me.

Fane took over Wharfedale in the 1990s, and released products which were more PA than hi-if, reasonable quality, Chinese made.

It looks like there is a speaker protection relay. Is that relay switching on?
If not, is there a DC level on the output of the power amplifier going into the relay. If so, you probably have a faulty output transistor (or two). Usually that would blow the fuse.

If the relay switches on, is there any output hiss or is it completely silent?
I'll get the multi-meter out and test it. I'm a beginner, are you able to point the speaker protection relay out to me? There is a general hiss when I turn it on, but that would be because of the sub speaker that is working.
 

Thread Starter

donny0m

Joined Oct 19, 2022
12
I'm not sure what the white substance is. Perhaps it could be glue. The attached photos show it on another component.

There is also no visible bulge on the big caps.IMG_3893.jpgIMG_3892.jpg
 

Thread Starter

donny0m

Joined Oct 19, 2022
12
So there are some additional speaker cabinets supplied with it?
Where are you connecting them?
I'm connecting them up to speakers that I know work. Additionally, the speakers that I purchased in the set with them work with a different amp.

I'm using the speaker outputs on the back plates to connect the speakers. Have I understood your question?
 

Ian0

Joined Aug 7, 2020
6,713
I'm connecting them up to speakers that I know work. Additionally, the speakers that I purchased in the set with them work with a different amp.

I'm using the speaker outputs on the back plates to connect the speakers. Have I understood your question?
You mean the terminals labelled “Speaker level INPUTS”?
Or the RCA phono sockets labelled ”line level outputs”?
 

Thread Starter

donny0m

Joined Oct 19, 2022
12
You mean the terminals labelled “Speaker level INPUTS”?
Or the RCA phono sockets labelled ”line level outputs”?
I connected the speakers to the Speaker Level Inputs. I used the line level input RCAs to connect to the phone music input.

RCA Line outputs are untouched.
 

Ian0

Joined Aug 7, 2020
6,713
”Speaker Level inputs” are INPUTs that accept a speaker-level signal. They are not amplifier outputs.
What you have is a add-on powered subwoofer. It is intended to add a subwoofer to an existing amplifier and speakers.
 

Thread Starter

donny0m

Joined Oct 19, 2022
12
”Speaker Level inputs” are INPUTs that accept a speaker-level signal. They are not amplifier outputs.
Oh crap! So this isn't a sub woofer amplifier that's meant to drive external speakers? There wasn't an amplifier with the sale so I incorrectly assumed the sub WAS the amp. How would I drive the external speakers then. Get a separate amp?
 

Thread Starter

donny0m

Joined Oct 19, 2022
12
”Speaker Level inputs” are INPUTs that accept a speaker-level signal. They are not amplifier outputs.
What you have is a add-on powered subwoofer. It is intended to add a subwoofer to an existing amplifier and speakers.
Got it. I'll look for an amp to power the set then, thanks a lot!
 

Thread Starter

donny0m

Joined Oct 19, 2022
12
If you are getting some hiss from the speaker, it is probably working.
Thanks Ian, it works.
Will the line out from the sub give me enough to power speakers or connect to a stereo amp to drive a pair of bookshelf speakers?
 
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