[corradizo]

After finding myself completely disgusted with my new bedroom tv's "speakers" I set out to find something I could build that would have high WAF. This meant small, really small and wall mounted. After going back and forth on the Overnight Sensations in a customized enclosure and the Helium's, I finally went with the Helium's due to their smaller size and since I could save time with the Parts Express flat pack. The Heliums are designed by Scott Sehlin and posted in the parts express speaker gallery here and on the Midwest Audio Club Website here. I bought all the parts from PE for these and they came in around $125 for the pair (this includes the enclosure flat pack!).

I'll be documenting my build (ok - glue and cut 8 holes...) as I go in hopes this will help some one. This will be my first set of speakers outside of my subs.

Here is the BOM:


300-7060 PARTS EXPRESS KNOCK-DOWN MDF 0.04 CU. FT. MICRO BOOKSHELF
015-3939 OHM 5W RESISTOR WIRE WOUND 5% TOLERANCE
027-414 DAYTON AUDIO DMPC-2.0 2.0UF 250V POLYPROPYLENE CAPACITOR
004-2 DAYTON AUDIO DNR-2.0 2 OHM 10W PRECISION AUDIO GRADE RESISTO
016-15 15 OHM 10W RESISTOR WIRE WOUND 5% TOLERANCE
027-421 DAYTON AUDIO DMPC-4.0 4.0UF 250V POLYPROPYLENE CAPACITOR
255-024 JANTZEN AUDIO 0.20MH 20 AWG AIR CORE INDUCTOR CROSSOVER COIL
260-294 ROUND SPEAKER WIRE TERMINAL CUP SPRING TYPE
269-303 FERRITE CORE CROSSOVER INDUCTOR 2.5MH 21 AWG 125 WATT
IMPORTANT: This is a clearance item because i'm cheap. When you knock out the Ferrite core, this becomes a 1mh inductor as is required by Scotts design.
275-025 DAYTON AUDIO ND16FA-6 5/8" NEODYMIUM DOME TWEETER
290-224 DAYTON AUDIO ND91-4 3-1/2" ALUMINUM CONE FULL-RANGE DRIVER

 

[corradizo]

Reserved

 

[corradizo]

Reserved again

 

[corradizo]

I've cut some holes, some too big. Back filled it with Spackle paste..love this stuff. I got my teeny tweeter pressed in really well. I have my woffer installed. I shaved the back side of the MDF so the woofer can breath. I built my 3/4" ID port. I drilled the external side 3/4" about half way through then drilled the back with a 1" bit. I sanded the PVC a little to press fit it in place. Now I'm mocking up the crossover.

Speaker pron:

 

[corradizo]

Think I can solder right to the tweeter and woofer tabs or should I get cramp on fasteners? I plan to hot glue the crossover pieces to the inside of the box.

 

[Bombelman]

Think I can solder right to the tweeter and woofer tabs or should I get cramp on fasteners? I plan to hot glue the crossover pieces to the inside of the box.

looking great ! pre-tin and just solder, would be fine... do not overheat...

 

[corradizo]

Thx, I did that on the wires and on the speaker tabs.

Pre tin the tab, and the wire, then put eh together

Shrink tube, cuz it was on sale at harbor freight...

I don't have a heat gun so I used the solder iron to melt it on..

I then ran the amp side wires through the hope in the MDF.

Ghetto iron holder, comes in handy.

Let's rock! They sound awesome!!! Huge even.

 

[corradizo]

Now I need to take them apart, glue them up, paint them and then make some speaker grills.

 

[corradizo]

My babies are in the bedroom! Not painted yet, not mounted, but daaaamn do they found big and so clear. I can't believe it. They do need a sub so I'll probably find a way to squeeze and si18 behind the couch

I tested them on the top of the chifarobe, not in the cabinet. For a little over 100 bucks, they are a great value. Those little ports really really pump!!

 

[corradizo]

Put together some grills for the Heliums. I glued a strip of wood to the back vertically and left it unpainted because I'm going to use the removable 3m Velcro tape to stick them on the wall next to each side of the TV. Each speaker weighs 3lbs so i should be good. They will hug the TV closely so I will run the wires from the existing wall holes behind the TV and to the speakers.

The more I listen the more I like them! I'm thinking to build a pair of Jeff Bagby's Quarks next for my office.

I still need a basic receiver for the bedroom and a sub to complete the 2.1 setup. My old pioneer all in one will need to go to the garage.

 

[eng-399]

The grills turned out great. I wish someone had 5 of these and a smaller sub. It would be nice to hear the difference between these and the Bose or the 321 Bose system to compare sq. Any word on the 2 18's behind the couch in the room.

 

[corradizo]

I got them mounted to the wall last night, you can tell the difference in the way they sound due to the baffle step compensation in the crossover. They still sound great, just a little bassy which when I get an actual reciever in the bedroom should be able to flatten them out.

I am still contemplating the sub. The bedroom is about 2500 cuft and we won't be playing very loud. So I'm not sure what to build yet.

I really want to build two 18" pa-460's in 2cuft sealed boxes as mid bass modules for the media area! Haha

 

[corradizo]

Pic

 

[corradizo]

So I decided to take some measurements of these little bad boys. The measurements are from after i put them up on the wall, i don't have any from before I did that. Also, the AC was running so i think that raised the noise floor. When I hung them on the wall, it seems like I had a sub in the room! MUCH more bass. I think the baffle step compensation in the crossover has much to do with it. I'm really green with respect to REW so i'll share a link to the file in drop box in hopes that someone with much more knowledge than me can comment on the measurements.

Here is the file: https://www.dropbox.com/s/kgmjdtsawyq24ac/heliums%20in%20the%20bedroom.mdat?dl=0


So i definitely need to flatten out the

 

[michaelddd]

Very cool! Thanks for sharing your build with us. Really dig the micro-ports with the elbow. No such thing as "doesn't fit." We make'em fit!

 

[corradizo]

Glad you like it!

On another note, I did a little measuring last night and it looks like I can fit a sealed 4cuft si ht18 between the couch and window in the bedroom. Yessssss. Now to find a great deal on another inuke3000dsp...

 

[eng-399]

Glad you like it!

On another note, I did a little measuring last night and it looks like I can fit a sealed 4cuft si ht18 between the couch and window in the bedroom. Yessssss. Now to find a great deal on another inuke3000dsp...

Pete that's great news glad to hear you can fit a 18 in there. I just got my inuke 3000dsp yesterday and got from sweetwater for 270.00 out the door only 10$ off but it helps. Chris was my sales guy ask for a deal on it. You should do Atmos next for the bedroom set up!!!! would be cool in there!!!!

 

[corradizo]

I think I might take one of my 18's up to the bedroom with the 3kdsp to try it out with the Heliums. I bet the tactile will be so much better since it's a closed room and suspended floor!

 

[cmckenzie]

Dude. I'm holding you responsible for my situation. Ive been hankering to build a speaker set after putting together a chip amp a couple of years ago. I became sold on your rational for the Helium over OSs.

I've spent the last week building my cabinets (Baltic burch cab with African mohogany baffle, I might paint the cab) and went through the parts I ordered based on the part lists in your thread. My electrical schematic comprehension isnt great.

Do you have a better wring pic for the cross over? I'm finding it difficult to build the crossover. I'm as good with an iron as a router, but I'm a novice with reading electrical schematics.

Thanks. I'll share pics once I have everything assembled.

 

[corradizo]

Glad you are building them!

This is the official thread from PE:
http://techtalk.parts-express.com/f...cromonitor?244673-Helium-a-true-micromonitor=

Check it out and also here is the schematic:

http://techtalk.parts-express.com/filedata/fetch?id=1192208

All the upside down Christmas trees connect to your black terminal except for the one after the squiggly in the circle, that one connects to your red.