Wharfedale i4T connections

[sunray]

2 hours ago, IA76 said:

I contacted Wharfedale direct from their website and they sent me this picture which ties in with the 70v layout in the manual but not the 100v one!

I believe that matches the manual perfectly

4 hours ago, DrV said:

5 hours ago, IA76 said:

using the 2KΩ setting

T1 & T2 = 1.008

T1 & T3 - just displays a 1

T1 & T4 - Just displays a 1

T2 &T4 - 0.013

Using the 200Ω setting

T1 & T2 = 1.008

T1 & T3 - just displays a 1

T1 & T4 - Just displays a 1

T2 &T4 - Just displays a 1

This is the meter

Well, I give up! There are too many unknowns. Don't suppose you can open it up and have a look? One thing I would say is that it's unlikely to have an isolating transformer as Ray shows but more likely an auto transformer (cheaper). However he has experience of installing such systems which I don't.

If it is an autotransformer then I would suggest that the speaker itself is connected between T2 and T4. Clearly 100V into .013k would be a lot more than 25W! That also means the supplier doesn't know what they're talking about. 

All that in red makes much sense, as the reading is higher than the maximum it can do little else,

Green; should not be the same, if it is 1.08KΩ then on the 200Ω setting it should be flashing 1 or if it is 1.008Ω it should be showing as 0.001KΩ on 2kΩ setting.

likewise blue; if it is 0.013KΩ it should read as 13Ω  on 200Ω setting.

 

My experience is never knowingly experienced an autotransformer. To quantify that; if I don't open an enclosure I wouldn't know and I have by no means opened a sample of everything I've worked with.

It may very well be an autotransformer however that doesn't make much difference to what we are discussing

It will still be similar turns ratio and usually with a thicker enamelled copper wire for the loudspeaker section.

Red numbers would be the terminals we have been referring to.

Edited November 14, 2023 by sunray

[IA76]

Now it finally makes sense! Thanks for all the input. It seems like the speakers had the stickers on for the i4 rather than the i4T but suprised the supplier got the terminals wrong as they sell a lot of 100v equipment.

Edited November 14, 2023 by IA76

[sunray]

31 minutes ago, IA76 said:

Now it finally makes sense! Thanks for all the input. It seems like the speakers had the stickers on for the i4 rather than the i4T but suprised the supplier got it wrong as they sell a lot of 100v equipment.

I think I may have mentioned that in post number 2 but this is a tricky area if you're not familiar with it.

I've been playing with 100V transformers for decades and much of it is second nature, it wasn't until I did the calculations for 474Ω & 104Ω that I calculated anything but some of those I've worked with never have got to the bottom of it.

A few yeas back I ordered several dozen speakers for a job and specced the T version (Fixed as 15W but 4 terminals; com/70V/100V/com), our buyer realised the version without the T (4 terminals; com/8Ω/8Ω/com ie loop in and loop out) was significantly cheaper, they arrived on site and the installers put them in and wired as low impedance. Lucky for me the labels were wrong.

Edited November 14, 2023 by sunray

[IA76]

20 minutes ago, sunray said:

I think I may have mentioned that in post number 2 but this is a tricky area if you're not familiar with it.

You did but learnt some new things with the extended discussion 🙂

[sunray]

2 minutes ago, IA76 said:

You did but learnt some new things with the extended discussion 🙂

I'm fine with that, as I mentioned it's a tricky subject  and comes with some unexpected results in the calculations.

[IA76]

The plot thickens. IAG group/Wharfedale sent an email saying this morning saying that they think that I may have the passive version of the speakers instead of the 100/70v version. They are looking in to it further.

Edited November 15, 2023 by IA76

[sunray]

17 hours ago, IA76 said:

The plot thickens. IAG group/Wharfedale sent an email saying this morning saying that they think that I may have the passive version of the speakers instead of the 100/70v version. They are looking in to it further.

If that is the case, T1 to T2 should read 0Ω, T2 to T3 should read 8Ω, T3 to T4 should read 0Ω

Equally you should hear a click with a 9v battery test across any pair of terminals on i4T but not T1 to T2 or T3 to T4 on i4.

 

[IA76]

I haven't heard back from them but opened it up to check and it has the 100v transformer inside.

[DrV]

2 hours ago, IA76 said:

I haven't heard back from them but opened it up to check and it has the 100v transformer inside.

Don't suppose you took a picture? It would be interesting to see (to me anyway 🤨)

Dave 

[IA76]

On 11/16/2023 at 12:50 PM, DrV said:

Don't suppose you took a picture? It would be interesting to see (to me anyway 🤨)

Dave 

I did.

[DrV]

Well, that answers the question about the pinout then. Never occured to me that there'd be a crossover in there too!

[sunray]

5 hours ago, DrV said:

Well, that answers the question about the pinout then. Never occured to me that there'd be a crossover in there too!

For an 8"x6" unit they are quite nice 2 way speakers, frequently specced by one of the consultants we regularly encountered.

Oh and a bracket that works.

Edited November 17, 2023 by sunray