Newbie Building a Lyra

[Kofi Annan]

Well, after much deliberation and a moment of clarity, I have decided NOT to build the J-Low Horn from Pass DIY (although I WILL do this at some point) in favor of the modest Lyra (details on the speaker here ).

I need to know a few things before I begin and since eveyone's been so helpful in the past, here are my questions:

The inductors that he has listed in his crossover schematic are listed as 16awg and 18awg. First, I'm hoping this means the same thing as "GA"-- wire gauge. Secondly, Parts Express only has 20GA air core inductors. Will it be a problem if I use these? If so, is there another place you'd recommend I shop to get the right gauge?

Also (and this is a really dumb one), where do you put the crossover circuit in the speaker? I mean, if you put it in the wrong place, it will interfere with the operation of the speaker, right?

Thanks in advance for any help you can give a schmuck like me. The first correct response will be in a drawing to win a pair of mittens or a scarf knitted by Mrs. Annan.

Also, if you can recommend similar speakers in this price range that you think would do better, be my guest.

Kofi

[Christof]

Awg can be thought of as GA

You can mount the X/O anywhere you wish, even externally in a small box. I usually mount mine to teh back wall. I use peg board to mount everything and then screw it to the wall putting rubber washers on the screw. I use the washers on both sides so the peg board floats and does not vibrate. There are probably a million ways to do this, you can't go wrong as long as everything is very secure...Lyras have lots of thunder in them!

Have fun

[officeboy]

Originally posted by Kofi Annan
Secondly, Parts Express only has 20GA air core inductors. Will it be a problem if I use these? If so, is there another place you'd recommend I shop to get the right gauge?

Kofi

Maybe you need to have a better look at PE
http://www.partsexpress.com/aircoreinductorpage.html

14,15,18,20 Awg all listed.

[Gaucho]

The inductors that he has listed in his crossover schematic are listed as 16awg and 18awg. First, I'm hoping this means the same thing as "GA"-- wire gauge. Secondly, Parts Express only has 20GA air core inductors. Will it be a problem if I use these? If so, is there another place you'd recommend I shop to get the right gauge?

Kofi,

AWG stands for American wire gauge. The 20 gauge inductors will work but heavier gauge inductors are better due to their lower resistance.

Also (and this is a really dumb one), where do you put the crossover circuit in the speaker? I mean, if you put it in the wrong place, it will interfere with the operation of the speaker, right?

It's best to keep a little distance between the drivers and the inductors in order to prevent magnetic linkage. Consider making the XO external.

Cheers,


Gaucho

ERSE inductors are avaliable at Zalytron:



http://www.zalytron.com

[Kofi Annan]

14,15,18,20 Awg all listed.

You're right! However, there still doesn't seem to be any 16awgs and the 18s I need are not there.

The 20 gauge inductors will work but heavier gauge inductors are better due to their lower resistance.

Cool, but did you mean that the lighter gauge inductors are better due to lower resistance? I'm not challenging here, just asking.

In other words, if my gauge is not available at Parts Express, should I go heavier or lighter?

Thanks again for all the great advice! I can't wait to order and get to work!

Kofi

[Kofi Annan]

Ahhh... wait a minute, here... Kofi is having a revelation.

This is just like the time I came up with the idea for UN Resolution 1441.

I think the lower the gauge number the heavier the gauge... right?!? If so, Gaucho's advice makes sense.

I need to stick to international conflict resolution. This DIY audio stuff is too taxing on the brain.

Can someone please confirm my wire gauge 101 question? Also, I need someone to wipe my nose.

Kofi

[Timn8ter]

The lower the awg number the heavier the wire; 14awg is thicker wire than 20awg and therefore has lower resistance (DCR).

I can't reach your nose.

[Kofi Annan]

I can't reach your nose.

You're just not tryin'.

Thanks for the info!

Kofi

[ingvar ahlberg]

Ok the wire gauge matter sorted, a good place to put the crossover is as on terminal panel together with input contacts.
Easily accesible when tweaking and simple wireplacement.

A good idea for the smaller caps is to parallell 1u250V polypropylene (Philips for instance) up to desired value.
Easy to change and a cheap way to attain top quality caps.

[Kofi Annan]

Thanks!

a good place to put the crossover is as on terminal panel together with input contacts

This is some sort of knockout panel on the back of the speaker, I'd guess?

A good idea for the smaller caps is to parallell 1u250V polypropylene (Philips for instance) up to desired value.

Actually, I just realized that I would have to add caps in parallel to get to the right values. I am planning on ordering Dayton polyprop caps for most of the capacitors (exception: there's a 60uF cap for the woofer and I'm going to use a non-polarized electrolytic for that one at the recommendation of someone on the speakerbuilder.net forum).

I'm going to use some .05uF polyester film caps in parallel with the Dayton polyprop caps to get to the right values. Will this cause a problem?

Also, in some cases, Parts Express did not stock the correct gauge for the inductors and they did not have a heavier gauge, so I had to go with a lighter gauge (example: traded a 16awg for an 18 awg). Will this make a big difference?

If you think I need to order different caps for the project, please let me know, but I thought the Dayton caps would work fine in the configuration I'm aiming for.

Kofi