The "Elsinore Project" Thread

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Are you attaching the waveguide to the tweeters or is everything held in by pressure (waveguide pressing back the tweeter into the cutout/stiffener)?


Tweeter recessed and mounted to sub front panel
Waveguide independently mounted to subfront with screws clear of tweeter.

Have to get the tweeter recess right so 3mm projection either just touches tweeter face or slight gap? Probably slight gap is best?
 
Some Waveguide fillers

Some one already mentioned it but think I'll try gluing in filler and then using filler around the edges. At this point I can level the the mdf and veneer over the front complete.

My fronts are 17.5 mm ply so have to recess Wg a little more into the sub front..

The tweeter looks to be significantly offset vertically to the waveguide in that photo, it it just stuck in roughly for a photo?
 
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The tweeter looks to be significantly offset vertically to the waveguide in that photo, it it just stuck in roughly for a photo?

Good Eye. The filler is not glued in position in that photo, I just let the filler sit there. On my other pair I have both fillers glued on - I put the tweeters in the recess and aligned waveguides over the tweeter, then placed the fillers over wg. Then I drew 3 scribe marks on the filler and cabinet so I could remove the components and glue in fillers..
 
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Tweeter recessed and mounted to sub front panel
Waveguide independently mounted to subfront with screws clear of tweeter.

Have to get the tweeter recess right so 3mm projection either just touches tweeter face or slight gap? Probably slight gap is best?

I would think you would want it to touch the face and leave no gap. Probably build a gasket out of felt or similar and use that to ensure a seal. Zaph did something similar for his TMM waveguide build.
 
Time to reveal something:

The Elsinore Mk5 has an until now un-announced feature: Right now in my system I am running it with a Current Amplifier.

Yes, the Mk5 are compatible with current drive, and I do believe this is the only multi-way speaker system, DIY or otherwise, that may be so described.

Some may be aware that Nelson Pass made the F1 "transconductance" amplifier. This simply another way of saying it outputs current.

Normal amplifiers are of the "voltage"kind, this is 99.999% of all amplifiers out there. My memory of what the text book says is that we have a voltage interface when the insertion (the load) loss is no more than 1dB or less. The voltage amp tries to maintain voltage (regulate it) irrespective of the load in Ohms.

Typically this means that the voltage amp should have no more than 1/10th the output impedance of the rated load in Ohms. So for an 8 Ohm speaker the output impedance should not be higher than 0.8 Ohm and for a 4 Ohm speaker no more than 0.4 Ohm. These are simply rule of thumb, but you could get precise figures if you figured out what output Z would cause exactly 1dB voltage drop.

The "current" amplifier works just in reverse. While a "voltage" amp is defined by it low output impedance, the "current" amplifier is defined by it very high output impedance. Maybe we should use the same rule of thumb and say it should be at least 80 Ohm for an 8 Ohm speaker system, and similarly 40 Ohm for 4 Ohm.

The Nelson Pass F1 had an output impedance of 80 Ohm. The later F1J had about 50 Ohm. So you can see the picture.

I have built a current amplfier with well over 100 Ohm output impedance, indeed as configured right now is is closer to 200 Ohm than 100 Ohm.

And it works!

I am thinking about publishing the amp design on a suitable forum here on diyaudio.com - which one and when is not yet decided.

BTW, it sounds VERY GOOD!

Cheers, Joe R.

PS: IF ANYBODY LOCALLY WANTS TO DROP IN AND HEAR THIS - YOU WILL BE WELCOME!
 
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I have built a current amplfier with well over 100 Ohm output impedance, indeed as configured right now is is closer to 200 Ohm than 100 Ohm.

And it works!

I am thinking about publishing the amp design on a suitable forum here on diyaudio.com - which one and when is not yet decided.

BTW, it sounds VERY GOOD!



I bet it does Joe and thanks for even contemplating sharing your hard earned work.

Still over the moon with the Elsinores by the way.:D



Cheers Paul
 
Hi Guys

Finally got around to get the website somewhere near up to scratch. Up to now scant mention of the Mk5, but pretty much all have appeared here already.

For those locally I will be able to help out with kits, everything but the construction of the box can be supplied as a kit or possibly do the crossover only. But not everybody needs the same thing, so PM me.

Cheers, Joe R.
 
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Work in progress
 

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