The "Elsinore Project" Thread

[Joe Rasmussen]

Originally posted by otto88
Joe,

That 830875 has a damn smooth response!

http://www.tymphany.com/datasheet/printview.php?id=12

How much are they here in Oz?

It's a honey and sounds as smooth as it looks.

I buy minimum qty of ten plus at a time and direct from the importer here in Sydney - cannot disclose. But www.speakerbits.com sells them for A$93.13 out of Melbourne, call Tom Mannning. That's quite reasonable, maybe he will discount for eight?

http://www.speakerbits.com/Default.a...upage=150&pi=2 scroll down at bit over half way.

# Speakerbits
# Unit F51 / 63 Turner Street
# Port Melbourne VIC 3207
#
# Phone: +61(0)3 9647 7000
# Fax: +61 (0)3 9681 8207

Joe R.

[nitronori]

I forgot, for L5 do you suggest a ferrite core coil or air core coil?

Since I have to buy them, ther's 1/2 euros difference beetween the two, not so much... In commercial speaker I've seen always ferrite core coil, but air one should produce less distortion. DCR here isn't critical right, could be as high as 1ohm.

C4 could be a bipolar cap like in C3?

For R3 I want to use a wirewound not inductive resitor, 6w rating is enough here?

For the rest of resistors Metal oxide 10W.

thank you

[otto88]

Thanks Joe, that's value!

[Joe Rasmussen]

Originally posted by nitronori
I forgot, for L5 do you suggest a ferrite core coil or air core coil?

C4 could be a bipolar cap like in C3?

For R3 I want to use a wirewound not inductive resitor, 6w rating is enough here?

For the rest of resistors Metal oxide 10W.

thank you

The L5 is part of the Conjugate Filter and in series with R4 (22R) so saturation is highly unlikely, so using a decent ferrite core should be no problem.

I use a BiPolar for C3 - in this case not detrimental to the performance. There are of course instances where they should be avoided like the plague, but I use TWO BiPolars in the Elsinores where they do a job that lowers distortion and actually makes for better sound.

Re resistors, I use 5W Dales non-inductive wirewound myself, more than adequate.

Joe R.

[Francois G]

Originally posted by Joe Rasmussen


Your local hardware store should have some 90mm PVC tubing used in plumbing, or try a plumbing supply store?

I too have not been able to find a ready-made port down here in Oz. There is a 100mm gap between the two vertical braces (rear panel) so that limits the size to that. Could use 3" or 80mm, but the length would need to be shorter to tune box to 35Hz and will also mean a significant increase in vent mac and possible noise.

Joe R.

I got my drivers and I'm planning box construction. That brought up the question of vent size. The above does not talk about inside of outside diameter. Since Joe specified a 90 mm hole I'm looking for a pipe/tube with OD 3.5 inches; probably 3" ID. Is this correct?

I have not been able to find a supplier with 3.5" OD PVC pipe - could any of you guys in the US point me in the right direction?

Thanks,
Francois

PS. Are there any Elsinore builders in the US? Please drop me email.

[Francois G]

Originally posted by Francois G


I have not been able to find a supplier with 3.5" OD PVC pipe - could any of you guys in the US point me in the right direction?

I think I got it! I need to buy a 3" pipe since PVC pipes are apparently specified by ID not OD. But then Joe wrote that 3" pipe may be too small in the quote above. It seems that 3" pipes have an OD of about 87mm. Is a 3" ID pipe a good to substitute for the pipe in the 90 mm hole Joe had intended?

I can buy 3" pipes at several places - sorry for the bother.

Thanks,
Francois

[Joe Rasmussen]

Originally posted by Francois G


I think I got it! I need to buy a 3" pipe since PVC pipes are apparently specified by ID not OD. But then Joe wrote that 3" pipe may be too small in the quote above. It seems that 3" pipes have an OD of about 87mm. Is a 3" ID pipe a good to substitute for the pipe in the 90 mm hole Joe had intended?

I can buy 3" pipes at several places - sorry for the bother.

Thanks,
Francois

Hi Francois

Needless to say it is the inside diameter that is the important factor. The required length of the vent changes accordingly to maintain the same Fb. So here are the figures, use as a guide:

Internal Dimension = Vent Length:

90mm = 88mm - OK

87mm outside = 80mm - OK

85mm = 75mm - OK

82.5 = 69mm - Borderline

80mm = 63mm - TOO SHORT

77.5mm = 57mm - TOO SHORT

75mm = 52mm - TOO SHORT

What concerns me the most by those lengths is that 52mm for an inside diameter of 75mm means that the vent does not finish far enough into the box and hence the area in front of the internal main brace. Because of this I would not like to use any less than just over 82mm inside diameter.

The other consideration is the peak velocity in the vent should be kept under 0.1 Mach (velocity) @ Fb for a reasonable rated SPL. The larger the diameter the greater the SPL before 0.1 Mach is reached.

ALTERNATIVE:

You could use postal tubes from you local post office. These are usually cardboard - but I have used them. A good idea is to use something to coat them - even just white wood glue that dries clear - to stiffen them further and protect them from any possible air moisture. If the right PVC pipe is not available, this will do the job at a pinch.

Joe R.

[Francois G]

Joe,

Many thanks for your guidance on vent selection. I ought to be able to make it work within the acceptable range you provided.

Regards,
Francois

[WS6Fury]

I must say, out of all the speakers I've seen so far within the affordable range whether diy or commercial, this is one of the most beautiful and meanest looking floor stander!!

Needless to say, this made me join the site So I have a few questions from a newb interested in this project as I love to make my own:

1) Is there a room size recommendation for these monsters?

2) Is there any special receiver requirement to push the speakers? ( I would be working off a Yamaha 3800)

3) Will this design work for low volume levels in HT use at night time (obviously made for ******* your neighbors off hehe )

Coming from the US, has anyone been able to come up with a complete and comparable parts list in the US to build the crossovers? I know madisound has the speakers...

Please forgive me if this has been answered someplace else in the thread. Too many pages to weed through with tons of info at work.

[rob323]

I can help with the easy questions.

2) Is there any special receiver requirement to push the speakers? ( I would be working off a Yamaha 3800)

I have run mine off 18 watt valve amps to a more than comfortable long term listening level, and Joe uses valve amps all the time. I'm pretty sure your Yammy has over 100 watts per channel and will do it standing on it's head, without breaking a sweat and give you irreparable hearing damage in no time .

3) Will this design work for low volume levels in HT use at night time (obviously made for ******* your neighbours off hehe )

I quite often listen at night with my son asleep in the next room, so down around 80 dB range. They do everything at low volumes that they do at stupid volumes. No need to turn them up to wait for the bass to catch up, so to speak. Of course you don't "feel" the sound like you do when the volume is turned up.

Please forgive me if this has been answered some place else in the thread. Too many pages to weed through with tons of info at work. [/B]

You obviously haven't read the Elsinore part of Joe's website from front to back then if you consider this a long thread