The "Elsinore Project" Thread

[jdkJake]

Originally Posted by ermat1234

Can anyone tell me the Tweeter and driver screw lengths. Also screw diamater.
Are allen head cap screws with huricane nuts best option to secure speakers into MDF?

I believe you stated you are using Joel's waveguides. These come with the hardware to mount the waveguide to the cabinet subpanel. They work fine.

As for the other drivers, I used #8 deep thread, pan head screws from parts express (black). I used the 1 inch, but, I am sure the 3/4 would work fine as well. That said, I built with BB plywood instead of MDF. I would expect the same screws would work fine, but, I do not have the direct experience with an MDF build. Machine screws with a hurricane nut may work far better for MDF. Especially if you expect to remove the drivers more than a few times.

[irext]

Originally Posted by jdkJake

I believe you stated you are using Joel's waveguides. These come with the hardware to mount the waveguide to the cabinet subpanel. They work fine.

As for the other drivers, I used #8 deep thread, pan head screws from parts express (black). I used the 1 inch, but, I am sure the 3/4 would work fine as well. That said, I built with BB plywood instead of MDF. I would expect the same screws would work fine, but, I do not have the direct experience with an MDF build. Machine screws with a hurricane nut may work far better for MDF. Especially if you expect to remove the drivers more than a few times.

WES Components in Sydney have some allen head self tappers in anodized black. They are 20mm long with 4mm dia shaft and 7mm dia head and bight in very firmly to the MDF front panel. They look very nice from the front and match the mounting hole size in the 6.5" drivers perfectly. All for the princely some of $2.05 for a bag of 20.

[jdkJake]

So, I have been listening to the Elsinores for a few weeks now. I have them pretty much aligned properly and the mids and treble, while slightly forward with the amp currently employed, are very, very sweet. Amazing imaging. The bass, well, something is slightly amiss, but, hard to place exactly what. Certainly not as extended as I was expecting.

So, time to break out the measurement tools and see what exactly is going on as I suspect I missed with the port tuning. Sure enough, the measurements tell the story.

The first picture is the impedance using Joe's crossover as designed.

The second picture, is with L4/R2/C3 taken out of the circuit to allow the port tuning to be derived from the impedance measure. The picture shows the port to be around ~27Hz. A bit low from the 33Hz target.

The third picture is with the port sealed. This allowed using a calculation to get a better estimate of the tuning (Fb = SQRT(Fh**2 + Fl**2 - Fc**2). This puts the port to be around ~25hz.

So, looks like I am a bit too long on the port or a bit too much on the dampening material. Either way, I am somewhere around 6 to 8Hz off of the target tuning. I suppose I could try a single layer of dampening material on the back panel vice the double layer currently employed, but, I would be surprised if that moved the tuning quite that much. That said, I am not sure. I lack the experience to say one way or the other.

First, I should probably calculate how much material would need to come off the port given the current amount of dampening material.

Let the finessing begin!

[tpate]

Jdkjake, When we tuned the port on my set I had several length's on hand, 1/4 inch increments and used duct tape to seal the gap around the port. I ended up using the shortest one I had on hand and siliconed it in place The 30 ohm resistors really tighten up the bass. If you have been enjoying the way they sound I don't think I would change the damping material until you try different port lengths.

[irext]

Originally Posted by jdkJake

So, I have been listening to the Elsinores for a few weeks now. I have them pretty much aligned properly and the mids and treble, while slightly forward with the amp currently employed, are very, very sweet. Amazing imaging. The bass, well, something is slightly amiss, but, hard to place exactly what. Certainly not as extended as I was expecting.

So, time to break out the measurement tools and see what exactly is going on as I suspect I missed with the port tuning. Sure enough, the measurements tell the story.

The first picture is the impedance using Joe's crossover as designed.

The second picture, is with L4/R2/C3 taken out of the circuit to allow the port tuning to be derived from the impedance measure. The picture shows the port to be around ~27Hz. A bit low from the 33Hz target.

The third picture is with the port sealed. This allowed using a calculation to get a better estimate of the tuning (Fb = SQRT(Fh**2 + Fl**2 - Fc**2). This puts the port to be around ~25hz.

So, looks like I am a bit too long on the port or a bit too much on the dampening material. Either way, I am somewhere around 6 to 8Hz off of the target tuning. I suppose I could try a single layer of dampening material on the back panel vice the double layer currently employed, but, I would be surprised if that moved the tuning quite that much. That said, I am not sure. I lack the experience to say one way or the other.

First, I should probably calculate how much material would need to come off the port given the current amount of dampening material.

Let the finessing begin!

It's interesting that you find the LF somewhat lacking. I must admit to occasionally thinking that they should have a little more energy in the LF region considering their significant volume. Then I listen to them another day and find the LF to be quite adequate (different mood I guess). I have not made any measurements at all and I know I really should (and will) do this. I have however considered removing some of the damping material from the rear of the cabinet. The material I used was not the poly wool as specified as I could not get my hands on it without buying large quantities at an unreasonable cost. I ended up using Acoustic absorbent material after much research. I used the least dense available but I'm starting to think it may still be significantly more dense than the poly wool batts. I will try removing half of the material from the rear portion of the cabinet to see what difference is made. I remember reading somewhere else on this forum of a constructor who removed damping material to achieve better LF. Joe Ras does go to some lengths to emphasize the importance of the correct density of the material. I just wish I had the exact same material he used so that there would be no doubt. But as you say "let the finessing begin" I am extremely interested in your findings and I'll keep you posted on mine.

Cheers.

[jdkJake]

Originally Posted by tpate

Jdkjake, When we tuned the port on my set I had several length's on hand, 1/4 inch increments and used duct tape to seal the gap around the port. I ended up using the shortest one I had on hand and siliconed it in place The 30 ohm resistors really tighten up the bass. If you have been enjoying the way they sound I don't think I would change the damping material until you try different port lengths.

Yeah, I am hesitant to remove any of the dampening material at this time. If I try anything, I would remove one of the layers from the back panel (I have a single layer of material on the sides and a double layer on the back). Although, this is probably the most important panel to dampen properly. As it stand now, my double layer is still slightly thinner than Joe recommends and the side panels slightly thicker. Probably best to leave well enough alone in that area.

While I have the drivers out, I will pop on those 33R resistors.

[jdkJake]

Originally Posted by irext

It's interesting that you find the LF somewhat lacking. I must admit to occasionally thinking that they should have a little more energy in the LF region considering their significant volume. Then I listen to them another day and find the LF to be quite adequate (different mood I guess). I have not made any measurements at all and I know I really should (and will) do this. I have however considered removing some of the damping material from the rear of the cabinet. The material I used was not the poly wool as specified as I could not get my hands on it without buying large quantities at an unreasonable cost. I ended up using Acoustic absorbent material after much research. I used the least dense available but I'm starting to think it may still be significantly more dense than the poly wool batts. I will try removing half of the material from the rear portion of the cabinet to see what difference is made. I remember reading somewhere else on this forum of a constructor who removed damping material to achieve better LF. Joe Ras does go to some lengths to emphasize the importance of the correct density of the material. I just wish I had the exact same material he used so that there would be no doubt. But as you say "let the finessing begin" I am extremely interested in your findings and I'll keep you posted on mine.

Cheers.

I don't think the bass is lacking per se, perhaps a bit rolled off in the deep, deep bass. I think the subsonic re-enforcement at 25Hz (current port tuning) only benefits a small amount of listening material whereas up in the low to mod 30's would hopefully suit a wider range of music. Being a quiet, lazy Sunday morning, I have some Bill Evan on right now that sounds absolutely wonderful.

But, this is all speculation at this point. My main goal is to get the speakers performing within Joe's stated design goals before commenting further.

BTW, Joe went with a couple different dampening material recommendations. First, he started with a wool/poly blend and then went to a pure poly solution. I think the density rating for the pure poly is captured on a picture somewhere in this thread. As for the wool/poly blend, the Monacor MDM-3 is probably the most widely available material that matches the original recommendation in everything but thickness. I got mine from MCM, but, I am sure there are plenty of sources if you are unhappy with the poly you are currently using.

[jdkJake]

irext,

Here is a link to Joe's poly material. It is R3.0 in density:

The "Elsinore Project" Thread

spoonted also recommended different material in this post:

The "Elsinore Project" Thread

Hope this helps.

[tpate]

I use a sub with my system, the only way I found to make the transition seamless is by using an amp with a variable phase control. I set the crossover at 40hz for the sub and run the Elsinores full range. A really good amp for the bass is a must. When I listen to how loud the sub is when the mains are off I find it hard to believe that little sound can make such a big difference.

[irext]

Well today I spent the whole day replacing the damping material in the rear chamber. The original material was acoustic absorbent material (the grey stuff) and I filled the chamber to the thickness specified by Joe Ras. The replacement material is made specifically for Speaker cabinet damping but is only about 10mm thick. I had to layer it to get the required thickness. (see attached photo). The difference is very noticeable. There appears to be much more energy in the LF region and it appears more extended. I am so glad you prompted me into action JK . I will now arrange to make the necessary measurements to ensure the box is correctly tuned but there is a definite improvement so far. Obviously my original material was just simply too dense and was actually reducing the box volume.