Bottleneck speaker competition (MD/VA/DC/DE/PA)

[Paul Joppa]

Not that there's more than the slimmest chance I'll be able to make it, but an idea would be to allow either a tweeter or a woofer but not both. A fullranger by itself is pretty constrained to the 6"-8" range if it is to have a balanced spectrum, and thousands of designs have been developed and are out there on the web. But making the choice between HF and LF augmentation is a more interesting design challenge which has not been much explored.

... Except of course for the standard 8"-12" woofer with 1" tweeter which s the conventional-wisdom standard in spite of the midrange compromises. Should there be a constraint on the crossover frequency to keep it to augmentation rather than an ordinary 2-way?

 

[castlesteve]

Ray,
    I think David is proposing a small fullrange driver with a bass driver to supplement the low ranges. We could restrict the cabinetry to be an original design and not a copy of someone else`s design. That would present somewhat more of a challenge to all the builders. There are all sorts of online programs to help with box design. i think that $200.00 and requiring an original design would be a sufficient competition. i suspect that a good fullrange unit in a well designed box with correct damping will defeat a 2 driver version due to driver quality, but we`ll see!
 

 

[RayP]

I like Paul's idea of a max of one crossover and restricted xover ranges. I suppose we could just say the xover should not be in the 300 to 5000 range or whatever range we come up with.

I also like Steve's suggestion of an original design but I doubt that any of us could come up with a totally new design. Perhaps we could redefine the suggestion to 'a design that does not have a web site with plans that you just copy'. You could take the concept but use different speakers. For example, you could take the MLK open baffle on a H frame and use a different woofer and full ranger from what MLK has already used.
http://www.quarter-wave.com/Project08/Project08.html

ray

 

[dbishopbliss]

Ray just posted before me, but we were thinking along the same lines...

I was proposing either an added tweeter or woofer, but not both.  This would allow for something similar to the Jim Griffin Jordan/Aurum Cantus design or the Martin King Jordan/Goldwood design.  That said, I think that we should require entries to be an original design.  I don't think a Fostex speaker with Fountek tweeter is the same design as the Jordan/Aurum Cantus. 

I think requiring folks to build their own enclosure might put some people out of the competition so I think we should allow people to purchase pre-assembled cabinets.

So, how about this:

- full range driver 4" or smaller
- can be augmented on the high end or low end, but not both
- must be an original design
- pre-built enclosures are ok
- total cost of drivers, crossover components, damping material, input jacks must be less than $200

 

[castlesteve]

  Are we agreed on this yet? Does anyone else have any more input?

 

[RayP]

I'm fine with it and I know what I will attempt to build.

ray

 

[castlesteve]

I'm fine with it and I know what I will attempt to build.

ray

  Me too. I`m going with something simple but hopefully good sounding. i just ordered the drivers!

 

[dbishopbliss]

I think we are close enough... I'm not going to do anything that would be different from any of the guidelines that have been proposed.  Don't really know what I will build yet.  Right now, I'm building a 1960's Marshall 4x12 cabinet replica for a friend.

 

[castlesteve]

  Did we stipulate a meet date? Hopefully some time in September or later. Most of these fullrange drivers do sound better with some time on them. If you like we can do the meet at my place.

 

[dbishopbliss]

Are you suggesting September for the competition or for a meeting to finalize the rules?  I'm hoping to learn about box/baffle design, crossovers, etc.  I'm not sure how much I will really learn in such a short time. 

 

[RayP]

I had talked to Fritz about hosting in October. We'll try to set a date.

I think the actual competition should be next year, it will be a while before I can actually build my design and I think I will have to try a few iterations.

ray

 

[RayP]

We had further discussion at the meet on Saturday and I think we came up with this:

- primary speaker to be full range. What constitutes a full range speaker? Like porn, we will know it when we see it.
- can be augmented on the high end or low end, but not both - the key here is augmented, crossovers in the 500 - 2.5k range will not be acceptable
- we will have two divisions for the full range speaker < 5 inches and >= 5 inches
- must be an original design but you can take an existing design and modify it with different speakers
- pre-built enclosures are ok
- total cost of drivers, crossover components, damping material, input jacks must be less than $200
- enclosures are not included in the $200
- competition to be held sometime in April but may be pushed back
- competition to be held at Steve's place in Stirling, VA but if somebody has a nice big room in the Baltimore area and would be willing to host, we would be grateful
- each entrant gets to pick one under 3 minute piece of music to be part of the music selection (send to me when you know what it is)
- probably will use David's 817 amp which should be enough for those 83db drivers

Let me know if I missed anything or got something wrong.

ray

 

[RayP]

Well my speakers are finally playing. Just a reminder that if you haven't started yet, it's probably time to get out the cutting implements. Building always takes longer than you think.

ray

 

[dbishopbliss]

I have a gretsch guitar and a fender amp that have been consuming my time lately.  I need to get those finished so I can start on my speakers. 

Question with regard to the rules... does there have to be a single primary driver or can there be multiples?  In other words, can I build a bipole or an array (or a bipole arrays)?

 

[RayP]

I'm not opposed to arrays, particularly if they are the full rangers. And I wouldn't mind if you had multiple woofers at the bottom end or multiple tweeters at the top end if they were the augmenting speakers. As long as the speaker finishes up to be predominantly full range.

These would be interesting even though they are on sale. http://www.madisoundspeakerstore.com/approx-5-fullrange/aurasound-ns525-255-8a-5.25-paper-cone-8-ohm/

It's tough to decide what speakers to use and what design to build. There's just so much stuff out there. At least I've got mine done so I can think of something else now.

I've been thinking about the judging process and I don't think we can hide the speakers this time and I suspect some speakers will sound best in different positions from others. I think we just make a modification to the scoring process so that everybody can score the speakers but you can't score your own speaker. I think that would be fair.

ray

 

[dbishopbliss]

with regard to the judging process... we might be able to hide them, but it would require a more binary type of process and simple criteria.  Something like the following:

Put speakers A and B in position behind a screen:  Play music and people choose which one they want to hear again. 
Put speakers C and D...
Put speakers E and F...

Then put the winner of round 1 against the winner or round 2 and repeat.  The hard part would be getting the levels the same and the positioning right before the judging begins. 

We might want to let the losers compete against eachother as well.  Then let the "winner of the losers" compete against the "winner of the winners" for the finale.

Probably needs a little more work to implement, but something along those lines could work.

 

[castlesteve]

  Unfortunately i will be unable to host the speaker meet due to a tree falling on the house during the christmas holidays. We have substantial damage which the insurance company is looking after, but the room we usually use will be full of kitchen supplies as we have to empty one end of the house. Hopefully we can find a new venue https://mail.google.com/mail/?ui=2&ik=e6330b38b3&view=att&th=13485c97bf92af52&attid=0.2&disp=thd&zw

 

[dbishopbliss]

I'm sorry to hear those Paramounts with MQ Iron and Teflon capacitors were completely destroyed by the tree.  As were your Klipschorns, and AudioNote DAC.  Hard to believe there is nothing left.  Oh well, I'm sure your insurance will pay to have them replaced.  

Ray said something about the library in Elkton being available again.  That is more central for most people, so perhaps that would work.  If not, I will check with my social coordinator and see about hosting in VA again.

 

[RayP]

Good lord, Steve. That was not what I was expecting when I checked in. Since my house is surrounded by trees, I can only sympathize. Hopefully nobody was hurt which is the main thing in these situations.

How about in a week's time, we start a discussion about the date for the competition. I should be able to reserve the library room and for me at least, it will be a much shorter drive. And when you see my speakers, you will understand why a local trip for me will be much better.

For those of you who don't know where the library is, here is the address:
301 Newark Avenue, Elkton, MD 21921

So if any of you are thinking of entering, how about you respond so we can get an idea of how many entries we will have. And remember, if you enter, you get to pick a piece of music that we will use to audition the entries.

ray

 

[2wo]

Wow, sorry to hear that Steve, Merry Christmas.

I plan to have an entry, although my plan is to use some drivers from the pile in the basement. So we'll see.

I would love to go back to the Library. Not only is it our roots but it is a much easier drive for me...John