Wharfedale titan 8 schematic

[diydidi]

Hi all!
Anybody have this schematic for me please!!!??

[lanternfish]

Hi. I am new to the forums.
Like diydidi I too am looking for a schematic for a Titan 8 Active.
The amp is briefly turning on then quickly shuts down. After that it has to be off for a while before attempting to switch on. I have to disconnect CON13A to keep the PSU on so am guessing that one of the amps (LF or HF) is shutting the supply down.
Any help will be much appreciated.
Thanks

[Eddie Woods]

Titan 8

Hi. I am new to the forums.
Like diydidi I too am looking for a schematic for a Titan 8 Active.
The amp is briefly turning on then quickly shuts down. After that it has to be off for a while before attempting to switch on. I have to disconnect CON13A to keep the PSU on so am guessing that one of the amps (LF or HF) is shutting the supply down.
Any help will be much appreciated.
Thanks

This is a bit of a late reply, however - these things seem to be double earthed and it confuses them. Remove the earth wire from the plug and it will work!

[Jazz P Bass]

Uhhm, Eddie: removing the earth wire is against most codes, to say the least.

Unsafe to say the most.

[J M Fahey]

Not sure what double earthed means either.

[Eddie Woods]

Uhhm, Eddie: removing the earth wire is against most codes, to say the least.

Unsafe to say the most.

Have you tried metering one of these units with this fault? You will be tearing your hair out after around 30 hours of failure.
The unit appears to be earthing on the jack lead as well as the plug lead - which is obviously not an intended design feature and one that Wharfdale seem to be in no rush to recognise or recall on.
You could clip out a couple of capacitors and this would also resolve the problem but that is definitely not advisable because then no one would know that the unit had been had been erratically rectified.

However, seeing as Wharfdale do not reply and don't have a solution - what is your solution to the problem?

[The Dude]

Removing the AC ground is not a good idea/ill advised as Jazz posted. The jack is supposed to be earthed to prevent electrocution, especially in the case where a user plugs a microphone directly into the speaker. If you have a ground loop connecting the unit to something other than a microphone, the proper method is to clip the ground on the send end of the connection cable. Here's a useful document showing proper interconnection methods,

Sound System Interconnection

[Eddie Woods]

Removing the AC ground is not a good idea/ill advised as Jazz posted. The jack is supposed to be earthed to prevent electrocution, especially in the case where a user plugs a microphone directly into the speaker. If you have a ground loop connecting the unit to something other than a microphone, the proper method is to clip the ground on the send end of the connection cable. Here's a useful document showing proper interconnection methods,

Sound System Interconnection

Thanks for the info - The method specified by AES48 is to use balanced lines and tie the cable shield to the metal chassis (right where it enters the chassis) at both ends of the cable.
Metal chassis? You really don't know these speakers.
I use these speakers as fold back monitors through a Yamaha PA and four years later with no AC earth nobody is dead or electrocuted because it is pretty near impossible to get electrocuted by plastic.
Your solution is not one - the real solution is for the suppliers to recognise the defect - but the recall costs probably make that somewhat prohibitive.
No one should have to be finding a solution to a manufacturing defect apart from the manufacturer.
I found a way round it and it works - you may not like it - but that's only your opinion.

[g1]

Schematic for Titan 8 Active here:
http://music-electronics-forum.com/a...7-titan-8a.pdf

[paleeman]

Thanks for the info - The method specified by AES48 is to use balanced lines and tie the cable shield to the metal chassis (right where it enters the chassis) at both ends of the cable.
Metal chassis? You really don't know these speakers.
I use these speakers as fold back monitors through a Yamaha PA and four years later with no AC earth nobody is dead or electrocuted because it is pretty near impossible to get electrocuted by plastic.
Your solution is not one - the real solution is for the suppliers to recognise the defect - but the recall costs probably make that somewhat prohibitive.
No one should have to be finding a solution to a manufacturing defect apart from the manufacturer.
I found a way round it and it works - you may not like it - but that's only your opinion.

Hi Eddie

It is very good to hear, that you have found a solution to this problem. Which is not really a problem, or a defect, but rather a manufacturing choice. Sure, they could've gone with the ground lift option, but they didn't. They chose to have the signal ground connected to earth with a 2R2 resistor. Probably, this is what is "confusing" you.

You may choose to lift the signal ground from earth. As one might know, in sound recording and reproduction, ground lift or earth lift is a technique used to reduce or eliminate ground-related noise arising from ground loops in audio cables. But the earth connection to the unit remains for safety reasons.

I advise you against removing the earth connection from the unit, because it's against code. While it is true, that it is pretty near impossible to get electrocuted by plastic, you should be very confident, that none of the insulating washers under the power transistors fail, 'cause that would be a real shame to have 400V DC finding it's way, back to your mixing console, via the jack ground, or even worse, to you singers microphone.

[g1]

So what happens if you lift the ground from earth at the input end, and leave it connected at the AC line end?
I would think that should be the proper way to avoid the "double earthed" issue.

[paleeman]

Yes, indeed. It would be the proper way.

You can achieve this in a pleasingly ingenious and simple manner by removing the R33 that connects the earth and the signal ground. Sure, it would have been easier if the brains at Wharfedale, implemented a ground lift switch in their design, but they didn't.

[The Dude]

Thanks for the info - The method specified by AES48 is to use balanced lines and tie the cable shield to the metal chassis (right where it enters the chassis) at both ends of the cable.
Metal chassis? You really don't know these speakers.
I use these speakers as fold back monitors through a Yamaha PA and four years later with no AC earth nobody is dead or electrocuted because it is pretty near impossible to get electrocuted by plastic.
Your solution is not one - the real solution is for the suppliers to recognise the defect - but the recall costs probably make that somewhat prohibitive.
No one should have to be finding a solution to a manufacturing defect apart from the manufacturer.
I found a way round it and it works - you may not like it - but that's only your opinion.

Oh, it doesn't matter if I like it. Do as you like. I'm just pointing out that this is not the safe/accepted/right way to go about solving the problem. This is not a factory defect requiring a recall. There's lots of gear out there that has the potential for ground loops when interconnected. Ok, they didn't put in a ground lift switch for convenience, but that's not a defect. If you buy a car without air conditioning and you get hot , does that mean the car should be recalled? The problem can be remedied by clipping the ground in the interconnect cable, which is the same as switching a ground lift switch. Both the send and the receive unit remain earthed. I'm not here to argue (only trying to help) and my solution is not merely opinion. It's the correct/accepted way of eliminating a ground loop in this application. If you choose to do something else, fine by me.

[g1]

I still am unable to see how the ground loop or 'double earth' is making the thing go into shut down, which is what Eddie seemed to be saying in post #3.
Oscillation?

[Jazz P Bass]

I think what Eddie is missing is the "reason" for having the 3rd prong ground pin on the plug.

It's not simply a matter of the enclosure being made of plastic or not.

It's the INSIDES that are relevant.

If mains voltage somehow comes in contact with the ground scheme INSIDE the amplifier, the 3rd prong will help to 'blow' the outlet circuit breaker (fuse) that the unit is plugged in to.