The "Elsinore Project" Thread - Page 56 - diyAudio
Go Back   Home > Forums > Loudspeakers > Multi-Way

Multi-Way Conventional loudspeakers with crossovers

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 29th June 2009, 06:20 AM   #551
diyAudio Member
 
Joe Rasmussen's Avatar
 
Join Date: Jan 2003
Location: Sydney, Australia
Send a message via MSN to Joe Rasmussen
Quote:
Originally posted by EUVL
Actually what is the pipe size (dia & length) for the Hamlet?
Same as Elsinore?

I searched but it wasn't mentioned explicitly elsewhere......
Patrick
Exactly, because it hasn't been determined yet. Diameter cannot stay the same as the Elsinore as that would make the port way too long, so to make the length manageable it has to have a smaller diameter.

So it comes down to what diameter PVC pipe is available. I think 65mm, aiming at a length no larger than 150mm and possibly less than 100mm.

Joe R.
__________________
The "Elsinore Project" DIY Speaker System
Custom Analogue Audio - we also support and promote non-profit DIY
  Reply With Quote
Old 29th June 2009, 10:08 AM   #552
Luke is offline Luke  New Zealand
diyAudio Member
 
Join Date: Sep 2001
Location: Wellington NZ
Send a message via AIM to Luke
Hi Joe,

I just read your write up on your website about the Elsinores. It states that the efficency is 94db and impeadance is 8 ohm.
In your graphs the efficency seems to hover around 90db and is pretty flat. Also I cant see how they can be 8 ohm as the mid bass are 2 8 ohms in series and the bass the same? Graphs I guess tend to indicate 12 ohm.
Am I correct here or have I missed something.
Im reasonalby interested in these but Im not sure they meet my requirements. I want efficency in the mid 90s for and lots of slam, dymanics, speed etc. Think these fit the bill, or are there more suitable projects I should look at? Im sure these are great speakers but its so hard to know without listening.
  Reply With Quote
Old 30th June 2009, 09:26 AM   #553
diyAudio Member
 
Joe Rasmussen's Avatar
 
Join Date: Jan 2003
Location: Sydney, Australia
Send a message via MSN to Joe Rasmussen
Quote:
Originally posted by Luke
Hi Joe,

I just read your write up on your website about the Elsinores. It states that the efficency is 94db and impeadance is 8 ohm.
In your graphs the efficency seems to hover around 90db and is pretty flat. Also I cant see how they can be 8 ohm...

Im reasonalby interested... I want efficency in the mid 90s for and lots of slam, dymanics, speed etc...
I don't recall claiming 94dB?

I don't have a quick answer, but here goes... [up he goes on his soap box]

This whole topic is a confusing concept and it is not hard to see why. You like high efficiency, yet most speakers are rated @ x dB sensitivity - they are not the same. High sensitivity only makes sense if the speaker is high impedance, only then do you have high efficiency. Sensitivy is SPL @ 1M with 2.83V RMS input and is irrespective to impedance, which could be 1 Ohm (some ribbons are) and hence low efficiency. Efficiency is based on current times volts for a specific SPL and is rather more difficult to quantify.

I am not trying to sound preachy, but what you, and I too, want is high sensitivity while maintaining as high as possible impedance. Also getting the load as resistive and even a little inductive also helps.

Go full range drivers and you will have it most of the time but with other limitations. That and other systems also trade genuine bass extension for higher sensitivity, which means that if you want, and I think you do, some real slam and dynamics you have to compromise a little. But where is the compromise?

Let's look at the individual Elsinore drivers, they are 89dB/1M SPL @ 8 Ohm. Put them in series parallel you get 95dB/1M SPL @ 8 Ohm. Leave there and you would have the goal you seek, right? But not so quick. If you want the bass to be there in a balanced degree you have to compensate for diffraction loss which is a theroretical 6dB. That will get you back to 89dB. (But a full compensation of the single 89dB driver would give you 84dB, no so hot, so it is still way better.)

Do you see the trend? And also the designer has an option to what degree to correct for diffraction loss? Only he can decide but whatever he does he will need to determine it to be between 0dB and the full 6dB compensation. I would think most aim for 4dB approx but there are those quite willing to sacrifice the full 6dB and perhaps even over-cook it and get even more bottom end, but sacrificing sens.

Indeed even with Lowthers @ around 96-97dB sens with full correction is only 90-91dB (rear horns don't boost sens). Bass below 100-200 Hertz have been truncated if you only aim for max sensitivity.

Now let's look at what the Elsinores do. They series the upper two drivers to give nominally 16 Ohm and 89dB. 89dB may not seem so good, but this does not need compensation and has high efficiency. Now look at the bottom two drivers and things gets interesting. we've halved the current while maintaing same sens. They too are in series and 16 Ohm, but at low frequencies are in series parallel with upper two drivers, so nominally 8 Ohm. But the roll-off is so gradual that it does two things, it fills in the diffraction loss at low frequencies and also, because it's so gradual rolling off (lese than 6dB/Octave), also manages to boost the overall sensitivity by several dB up to above 1500 Hertz and then the gradual take-up by the tweeter maintains it above that.

In practice when comparing with other speakers rated at 88-89dB, the Elsinores sounds noticeably louder. This was noticed when changing speakers without disturbing the volume control setting. At one time this was done with a known reviewer in the room and he actually was the one who turned down the volume control. I took the opportunity to ask how much he estimated he reduced the volume by and he said 4 or maybe 5dB. This certainly puts it above 90dB somewhat.

As for my graphs you comment on, well I am conservative when I set it up and you have just given me full justification for doing that. At least I make no false claims. But it is known that manufacturers claims are not always correct and also SPL is not the easiest thing to calibrate and measure.

Re the rated/nominal impedance of a loudspeaker, I follow the well estabished convention that the impedance must not drop below 0.707 times rated impedance. So an 8 Ohm should not drop below 5.65 Ohm at any frequency and 4 Ohm not below 2.85 Ohm etc. A 16 Ohm not go below 11.3 Ohm.

Re coming back to full range drivers, I have a pair of Visaton B200 and the manufacturer recommends a contour filter that compensates for diffraction loss. It ends up about the same as the Elsinores even though rated 96dB. Some do similarly with other full-range drivers and some like it, others maybe not. But it is tweakable to suit taste. So full range high sensitivity do not offer as much hope if you want a bottom end to match. So what do they do (and I heard a major Lowther horns on the weekend doing this) add a sub-woofer that can be very hit and miss.

Finally, and this sorta sounds a bit black magic, but the Elsinores have another quality that numbers just don't even hint at. Their ability to provide that certain jump factor and incredibly low dynamic compression, they just don't need a big muscle amp to get going and produce a really powerful sound. Do they sound louder than they measure? I can say that we did a controlled comparison between two CD players and matched their outputs to 0.07dB and yet the player that had superior dynamics gave the impression of being several dB louder. It was actually 0.07dB lower. This was heard by everybody in the room. I am quite sure the same can be applied to speakers etc.

I use the Elsinores currently with a 20W amplifier and have also used them together in a large carpeted community hall where Audiophile Society of NSW meet (the amp won the major blind shoot-out earlier this year) and it went quite loud indeed. It has also been tried with 6 Watt amplifiers and often surprised listeners that a speaker of this size is so capable with such a small amp. But since I like "Child in Time" by Deep Purple at fairly high SPL, then 20 Watts is quite nice in a thunderous way.

Now what about a 2 metre high Line Source? That could give you 101dB before compensation using 12 of the same drivers. It would be a 6 Ohm system. One day...

Joe R.
__________________
The "Elsinore Project" DIY Speaker System
Custom Analogue Audio - we also support and promote non-profit DIY
  Reply With Quote
Old 1st July 2009, 07:26 AM   #554
Luke is offline Luke  New Zealand
diyAudio Member
 
Join Date: Sep 2001
Location: Wellington NZ
Send a message via AIM to Luke
Hi Joe, thanks for your thorough explanation. I understand what you say about specs being misleading, and I see how difficult it can be providing specs of loudspeaker.
I need to read your post again several times to fully digest it all. But I do get the gist of what your saying.
  Reply With Quote
Old 1st July 2009, 11:35 AM   #555
diyAudio Member
 
Joe Rasmussen's Avatar
 
Join Date: Jan 2003
Location: Sydney, Australia
Send a message via MSN to Joe Rasmussen
Quote:
Originally posted by Luke

I need to read your post again several times to fully digest it all. But I do get the gist of what your saying.
Thanks, I think reading it a couple of times and it's not too hard to get the gist of it. I do hope that you give serious consideration to building the Elsinores. I don't think you will be disappointed as this is a speaker with a big sound and yet surprisingly modest power requirements.

Joe R.
__________________
The "Elsinore Project" DIY Speaker System
Custom Analogue Audio - we also support and promote non-profit DIY
  Reply With Quote
Old 1st July 2009, 11:42 AM   #556
Salas is offline Salas  Greece
diyAudio Chief Moderator
 
Salas's Avatar
 
Join Date: Oct 2002
Location: Athens-Greece
Quote:
Originally posted by Joe Rasmussen


I hear what you say, but maybe I'm into "soft sound"? Mind you, never been accused of that. As for series parallel, that is obligatory in line sources and I am of fan of that. One day I want to do a two metre high line source, great potential genuine efficiency and equally potentially low distortion.

But will most likely let people opt for both variations in the Hamlet, it all depends how the results stack up.

Joe r.

I got softer sound in that experiment, I don't say its the norm.
  Reply With Quote
Old 11th August 2009, 01:29 AM   #557
diyAudio Member
 
critofur's Avatar
 
Join Date: Jan 2004
Location: Columbus, OH
Send a message via AIM to critofur Send a message via MSN to critofur Send a message via Yahoo to critofur
I think both types of Elsinore woofers are out of production and not in stock in the main US retailers now? Unfortunate, I like those woofers.

Shouldn't be too hard to switch to the phase plug versions of the woofers. The Peerless Nomex HDS "Exculsive". (By switch I mean design a new crossover)
__________________
Critofur
http://www.ohmspeakers.com <- all the folks here are my friends
  Reply With Quote
Old 27th August 2009, 06:19 PM   #558
diyAudio Member
 
Join Date: Feb 2007
Location: Gainesville, FL
The midwoofers are still available online for $55 apiece. Build on!

I got temporarily distracted from the construction of my concrete Elsinores, but I will be resuming very soon. I'm thinking that these should be very neat.
  Reply With Quote
Old 10th September 2009, 01:32 AM   #559
rob323 is offline rob323  Australia
diyAudio Member
 
Join Date: Jan 2007
Location: Brisbane, Australia
Joe,
Email sent, need your input please.
Rob.
  Reply With Quote
Old 13th November 2009, 07:54 PM   #560
diyAudio Member
 
Join Date: Nov 2009
Location: Saskatoon, Saskatchewan
Default Damping material

I am going to build the Elsinor MK3. Just sourcing out parts at this time.
All is available but the Wool/dacron damping material.
Any ideas what would be a match available in Canada/US?
after reading some of the post I am eager to construct.

Tim
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
"Proac 2.5 clone" or "Elsinore project" Joel Wesseling Multi-Way 10 26th May 2011 05:51 AM
A thread to post your "project files" critofur Multi-Way 10 21st March 2008 12:50 PM
"compact loudspeaker factory visit from "magico mini" thread Nanook Multi-Way 2 4th January 2008 07:30 AM
The "Really simple and cheap speaker designs for the newbie!" thread. Spasticteapot Multi-Way 5 19th March 2006 04:16 AM


New To Site? Need Help?

All times are GMT. The time now is 09:44 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2