Newbie Building a Lyra

[MITMechE]

check www.madisound.com they have 16 ga air core inductors.

I'd probably go with the Jantzen 15 ga inductors if you really want to get everything from partsexpress.com

You probably won't be able to tell a real difference either way, but when in doubt I think it's best to go as closely as you can to Wayne's design.

[ingvar ahlberg]

I'd still like to know, however, if the sound difference between the midrange inductor at 20awg (bobbin-wound air core) and the inductor 18awg (air core, not bobbin-wound) is noticable to your average schmo.

No one will hear any difference, if they dont know whats there, and if You tell them and they here it You probably have caught them lying.
The resistance rise going from 18 to 20 awg is in milliohm range, if You plan to use them as stage monitors at Hollywood bowl with
a 1kW pa amp at full throttle, this makes a difference but i think Your drivers would dislike that.
The bobbin is just more convenient to wind the cu wire on, nothing else. Go with the inductors easily obtained, and good luck,- the Lyra is reminiscent of the best AR and Roy Allison 70´s designs in sound- realy enjoyable.

[Kofi Annan]

Thanks! That's what I wanted to know.

I actually wound up ordering most of the inductors from Madisound. I used a steel core (Sledgehammer) instead of an iron core for the inductor in the woofer (guy at Madisound said there would be no difference) and I got some heavier inductors (Sidewinders) from him in place of a few others (only changed about 2 gauge).

I can't wait for this stuff to arrive so I can start building. Any tips on how to best parallel the caps? I could just tie together the leads, but I'm thinking I could use a terminal strip to connect them together. I think in one case, I will need to parallel four caps, so it may get messy if I don't have a plan.

Thanks again for all the great advice! I'll post some photos when the building is complete. Now its just waiting for the parts....

Kofi

[Gaucho]

Thanks again for all the great advice! I'll post some photos when the building is complete. Now its just waiting for the parts....

Cool, can't wait to see the pics. Have fun!

Gaucho

[navin]

Originally posted by Kofi Annan
Thanks for the explanation. I'd still like to know, however, if the sound difference between the midrange inductor at 20awg (bobbin-wound air core) and the inductor 18awg (air core, not bobbin-wound) is noticable to your average schmo.Kofi

dude we are not average "schmo"s here. Neither is Kofi Annan :-)

The average schmo gets himself a bose or sony.

the non average schmo decides which car to buy based on how a properly installed stereo in it will should (never mind fuel mileage, cost of maintanance, and what JD power and Consumer Reports say).

In fact I have just rejected a car after the dealer told me I cannot change the car's stereo and that the factory supplied 6 CD changer/tape deck are "all you need". The factory supplied system did not even have pre outs!!!!!! most of us are NON average schmos!

as far as hearing things are concerned it pays to have family members who have slowly been trained to listen (instead of hear) and use them as judges.

my wife and sister can detect small changes in the speaker ccrossover. changes that LSP Cad claims are only 0.5db. and they dont know what changes to expect. their ears are my 1st judge.

[Kofi Annan]

my wife and sister can detect small changes in the speaker ccrossover

Please send your wife and sister to the UN building this weekend. Chirac and I will be there putting together the Lyra crossover and we will need their expertise. Just tell the girl at the front desk that Kofi says they can come in.

While I have your attention (and since I've never ordered speakers before), I have some bonus round questions for you (plural):

Although I ordered some mounting screws, I'm assuming that the speakers will come with some kind of mounting kit and instructions. It can't be that hard as long as they tell you how big to cut the holes, but I thought I'd check anyway.

Also, speakers in the Lyra are supposed to be "flush mounted". I imagine that this means the speaker structure should be flush with the MDF and I'm hoping that the speaker documentation will come with information on how deep the recess should be for a flush mount. Can anyone confirm?

One last thing-- there is no mention of any required stuffing for the inside of the speaker box. Does anyone know if its best to stuff the box with foam / speaker stuff or should I leave it alone for best performance. I don't mind messing with it, but I just wanted some opinions.

Kofi

[ingvar ahlberg]

I do agree with Navin that we hear differences totally unmeasurable, was refering to the case with Kofi´s inductors which will be allright, and besides, who wants a finished project?
Isn´t that what this is all about, keep tweaking and improving?
How many of us has left the cabinet of a bought amp unopened for more than five minutes?
As for the family doubling as listening panel i also agree but i´m fortunate enough to have the absolute subjective reference living in this family:
The cat, Yes the same one that makes a mess in polyurethane compound and has managed to claw the needle off from one of the Ortofon SPU´s, she has a favourite spot in the middle seat in the music sofa. When i play music, anykind, she remains in place, purring, whatever level. On the rare occasions i play a CD she leaves, whatever music, whatever level.
Mounting screws: Use T-nuts and machine screws, at least for bass unit. Recession into baffle is not critical, You will gain more from attaching an absorbing "fence" of felt or such around the drivers.
Stuffing is important, a globaly available damping material would be Acousto Q, a good idea is to attach felt mat to all inner surface prior to stuffing, ( green felt mat sold cheaply at auto spare supliers) The Lyra should be quite heavily stuffed so start with filling the cabinet loosely and listen, if bottom end seems soft add and keep listening.
And Navin, i agree on the car issue too.

[Kofi Annan]

OK-- Mrs. Annan has indicated that we are short on cash, so I'm thinking I can get away wiith some Dacron (polyfill) stuffing from the crappy craft store that she hails. Will this do?

Also, I believe I need to stuff the sides of the enclosure rather than having the stuffing fly all over the place. Can you offer any stuffing tips?

Recession into baffle is not critical, You will gain more from attaching an absorbing "fence" of felt or such around the drivers.

Will this speaker gasket do?

Anyway, I intend to recess them since I think it will at least look better, but do you know if the recess measurements are included with the speakers, or will I have to measure? I suck at measuring.

Kofi

[ingvar ahlberg]

The polyfill will do allright, as the box should be pretty much filled ( lightly packed) with the damping material it will stay pretty much where it is, but do try the felt attached to inner surfaces.
The gasket is for making the mating surface of driver and box airtight. Recessing do look better, there will propably not be any advice or measurements supplied with drivers so look up the yardstick. You can still use the absorbing fence even though drivers are recessed with the same gain. The craft store is bound to have ample supply of suitable material.

[Kofi Annan]

Alright! Thanks for all the advice. My parts should arrive tomorrow and I suppose I'll start building the crossovers.... tomorrow.

Thanks again-- I'll post pictures either when they're finished or when I frog it up so bad and I freak so far out with anger that I need someone to look into the madness in my eyes and feel my murderous rage as I slowly descend into the Void of Anguish to be consumed by the All Cleansing Fire of Rage at which point I will be reborn into a metalloid inductor-charged speaker-like being who will wreak havoc on his tormentors, bringing unto them their ultimate death, resting only to conjure beings of similar ilk but with different wire gauges and DCR ratings who will wrest from the world any remaining traces of the Holy and the Just so that all of our kind may live in a world of Chaos and Ruin WITHOUT ANY SPEAKERS.

Thanks!
Kofi