ER18 build (for real this time!)

mattsk8

mattsk8

Full Audioholic
Regarding veneer, it looks like the dimensions of the ER18 don't play nice with standard paper backed veneer sizes. I would like to run the veneer with the grain running vertically, up & over the speaker. The way I see it (44.5+44.5+9), that equals about 98", standard veneer is 8' or 96" long unless it's special order, standard veneer isn't long enough to do the job. Hope I'm explaining clearly here.

I've thought about putting a piece of trim, say 1.5" x 1/4" thick, on the lower end of the cab, that would take up some room, but , not sure how that extra trim is going to look with the floating shadow piece effect.

Any thoughts ? When you make your own veneer, how thin can you cut it ??


Dave
So going from memory (I'm at work right now working very hard :)) those cabinets are 13" deep x 9" wide x 44 1/2" tall. If you had a 4x8' sheet, you should be able to get 2- 13" x 44 1/2" pcs for the sides, and your 9" wide x 44 1/2" pc for the front to equal a used portion of 35" x 44 1/2". That'll leave plenty for the top of the cabinet and you'll have only used [less than] 1/2 of the 4x8' sheet of veneer. I'd paint the backs satin black and veneer the rest- that's how I did those tritrix and it looks very professional plus saves on veneer; but, if you're going to do that I hope you have your MDF endgrain exposed on the sides rather than the front and back. Its waaaaay easier to paint the back if you don't have to bury MDF endgrain. How you finish that front baffle could be a game changer though, but I think you would still have plenty of veneer even considering all the different baffle options. Hope that helps!

As far as making veneer goes, it's a much different process. Basically I'll take some 1" thick rough sawn cherry and resaw it w/ my bandsaw into (hopefully) 3- 1/4" thick pieces. Then I'll finish plane those down to my finished thickness of 1/8" w/ my planer. So my finished veneer will be 1/8" thick x however wide the board was. A LOT of work but the finished product is very pretty and real looking, plus w/ the thicker veneer your round over options are almost endless for finishing the corners and edges of the cabinets. I may even just try for 2- 1/4" thick slices out of each board instead of 1/8", just so I can get those bigger roundovers (like a 3/4" ro instead of a 3/8"). If I just confused the crap out of you let me know and I'll send you a link to the process!

If this process appeals to you, you might be able to get hardwood finish planed to those thicknesses from Woodcraft (or a similar store) for probably even cheaper than you'll pay for your veneer. Just a thought but don't think of it as a money saver cuz it takes a LOT more time to apply than standard veneer!!
 
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David LR

Junior Audioholic
Thanks, Matt-I understand what you are saying. However, for it to work that way, the veneer grain would have to be oriented horizontally. I guess I didn't explain myself well. Not sure I like the horizontal look. What I"m trying to do is run the grain vertically, up & over the cab, down the other side, doing the best I can to match the grain at the corners. So, I would need to use the long dimension of the 4x8 which is 96", I need at least 98, not even allowing for 1/16-1/8 wastage at the edge transitions.

You're right, though, plenty of material if I do it the efficient way, just not sure I like that look. I could probably get used to it though, I"m not going to buy TWO 4x8 sheets just so I can have the vertical look.
 
mattsk8

mattsk8

Full Audioholic
I get it, you want the grain to be continuous from one side, over the top, then down the other side- correct? I'm not sure if I'd be too worried about that cuz no matter what you'll have the front and rear baffles to contend w/, unless you're doing those black. Are you using round overs on the top?
 
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David LR

Junior Audioholic
Correct, yes, that's the idea

I guess it depends on the kind of look you're going for.
These speakers in the Gallery section at Salk Sound are pretty much
have the look I want, most have the grain running vertically although you can't
see if they tried to match the grain. Probably did, the craftsmanship looks superb.

SongTower Images
 
mattsk8

mattsk8

Full Audioholic
Correct, yes, that's the idea

I guess it depends on the kind of look you're going for.
These speakers in the Gallery section at Salk Sound are pretty much
have the look I want, most have the grain running vertically although you can't
see if they tried to match the grain. Probably did, the craftsmanship looks superb.

SongTower Images
Are you going to do round overs?

IMO, I think the front baffle to the sides of the cabinets are more important for grain matching than sides to top. Going over that in my head, no matter what you do, it would be impossible to match the front baffle grain to both sides if you matched sides to the top. If you were extremely careful and good w/ a utility knive you could get the top matched to the sides and get the front baffle matched to one corner, but you still would have to contend w/ the other side of the front to the cabinet side. Very confusing :p

I would worry more about front baffle to sides for grain pattern if it were me. I'm guessing you're going to do the black baffle around the drivers as well, correct?
 
mattsk8

mattsk8

Full Audioholic
Progress! Slooowly but surely. Sorry to anyone anticipating this, I shouldn't have put a time on my "hope to complete". I think I've said a couple weeks a few times now over the coarse of a few months :eek:. Busy busy

Anyhow. I have all the dados and rabbets cut in. I also have the veneer for the sides of the cabinets cut. Originally, the plan was to match that table's design. Then, after a bit of resawing and planing, I had some nice bookmatched pcs so I decided to go that route- mainly because it would be way easier. Unfortunately, I got a little arrogent w/ my planer and tried to take the veneer down to 3/32; needless to say I found the limits of my planer for veneer thickness! Ended up taking some decent chunks out of a couple pcs so I decided to go back to the strips to save on cherry.

Here's some pics of the strips I plan on using for the sides



Pic w/ the cherry baffle glued on, braces, rabbets and dados



I cut a 1/4" channel in the bottom of the baffle so I can tuck the 1/4" thick veneer under it. That way I won't have to match the contour of the radius on the bottom of the baffle



A pic of the baffles w/ the drivers marked out and ready to be routed in. By the time I had em ready for the router it was after 10pm n didn't want to make new enemys next door; should get those cut out tonight. Then xovers, then assemble cabinets!! Getting excited! I threw that board on them just to show it, it's the wood I started w/ (cherry). Resawed that into the veneer I'm using.

 
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David LR

Junior Audioholic
Lookin' good, Matt ! You've obviously got some great wood working skills.

No way I would have glued beautiful cherry baffles onto the underlying MDF before cutting holes. I've already screwed up on one of the baffles, had to make another one.

Question- how thick are the veneer strips you've cut for the sides ?? Just wondering how much width can be added before interfering with the original baffle step compensation designed into the crossover network.

I need to post my progress as well, working on routing driver holes in the baffles. I messed up on the depth setting on a woofer hole, way to deep for a flush mount, so, had to start over on that one ! AARGH !

Cherry is one of my favorite woods, looking forward to your finished product.

Dave
 
mattsk8

mattsk8

Full Audioholic
Lookin' good, Matt ! You've obviously got some great wood working skills.

No way I would have glued beautiful cherry baffles onto the underlying MDF before cutting holes. I've already screwed up on one of the baffles, had to make another one.

Question- how thick are the veneer strips you've cut for the sides ?? Just wondering how much width can be added before interfering with the original baffle step compensation designed into the crossover network.

I need to post my progress as well, working on routing driver holes in the baffles. I messed up on the depth setting on a woofer hole, way to deep for a flush mount, so, had to start over on that one ! AARGH !

Cherry is one of my favorite woods, looking forward to your finished product.

Dave
Thanks for the compliment! As far as thickness for the veneer on the sides, that's why I tried to make that veneer as thin as possible. I ended up w/ 3/32" so it should only add 3/16" to the total width of the front baffle's original design. I'm going to do 1/2" round overs so I'm hoping for no noticable difference. I'm going to make the veneer strips for the front 1/4" thick just cuz the thicker it is, the easier it is to make and I'm all about less work ;).

I did get my holes cut in. I made my depth 3/16" for the woofers and the tweeters. Getting the diameter for the actual woofer hole was a little tricky. I did end up a teeny bit heavy because when I did my practice hole in a piece of mdf at 5 11/16" the woofers were a bit tight, I would've had to tap them in. I made them 5 3/4" which is a bit loose but my circle jig only goes in 1/16" increments. Here's a pic w/ the holes cut in. I do have a few burn marks to recon w/. Hoping they won't show w/ the drivers mounted cuz that would be a pain to sand out!



I do have a question, How do I take the .1 mh 19 gauge inductor down to .06 mh? It says to unwind it, but how do I know how much to unwind to get it to .06mh??
 
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David LR

Junior Audioholic
"I do have a question, How do I take the .1 mh 19 gauge inductor down to .06 mh? It says to unwind it, but how do I know how much to unwind to get it to .06mh??"

Never done that myself, from online reading though, I know you have to have a measuring device of some kind, don't know if an ohm meter is the right one, but something like that. I think you just incrementally cut off a small portion, measuring each time until you get your target value. By small I"m assuming something like 1/4" each time, but, please don't take my word on that. Maybe somebody else can chime in with more knowledge than I.

By the way, nice look on the baffles, I like how you stopped the radius & than transitioned to the horizontal section. Must have been a little tricky to do.
 
Swerd

Swerd

Audioholic Warlord
"I do have a question, How do I take the .1 mh 19 gauge inductor down to .06 mh? It says to unwind it, but how do I know how much to unwind to get it to .06mh??"

Never done that myself, from online reading though, I know you have to have a measuring device of some kind, don't know if an ohm meter is the right one, but something like that. I think you just incrementally cut off a small portion, measuring each time until you get your target value. By small I"m assuming something like 1/4" each time, but, please don't take my word on that. Maybe somebody else can chime in with more knowledge than I.
To measure inductance you need an LC meter, such as this Digital LC Meter 390-570. A few years ago, I found a less expensive one on Amazon. Poke around to see what you can find now.

All I do is unwind the coiled wire until the meter (attach the leads to both ends of the wire) reads the desired inductance value. As wire is unwound from the spool, it no longer acts as an inductor, so you don't have to cut wire until you have the value you want. After making the cut, I use sand paper to scrape away the lacquer coating from about ½" of the end of the wire so I can solder later.

About the burn marks where you cut the recess for the drivers. I usually use a black marker, like a Sharpie pen, to blacken any visible part of the recess cut. Maybe that will cover the burn marks without sanding.
 
mattsk8

mattsk8

Full Audioholic
To measure inductance you need an LC meter, such as this Digital LC Meter 390-570. A few years ago, I found a less expensive one on Amazon. Poke around to see what you can find now.

All I do is unwind the coiled wire until the meter (attach the leads to both ends of the wire) reads the desired inductance value. As wire is unwound from the spool, it no longer acts as an inductor, so you don't have to cut wire until you have the value you want. After making the cut, I use sand paper to scrape away the lacquer coating from about ½" of the end of the wire so I can solder later.

About the burn marks where you cut the recess for the drivers. I usually use a black marker, like a Sharpie pen, to blacken any visible part of the recess cut. Maybe that will cover the burn marks without sanding.
Guessing that gadget does something that my auto ranging digital multi meter doesn't do. Maybe a future tool purchase but I need to hold off from it for now. I have to get a few things from Meniscus (binding posts, and threaded inserts) so I'll either just get the .06mh ones from them or have them unwind the ones I have. Thanks again for the input Swerd!

By the way, nice look on the baffles, I like how you stopped the radius & than transitioned to the horizontal section. Must have been a little tricky to do.
It was actually pretty easy (ish). I wanted that channel under the baffles to tuck the veneer under as well, so I made the baffle w/ the radius 1 1/2" less wide than I wanted it, then trimmed around it w/ some 3/4" pieces. Basically I cut the baffle, then made the radius on the bottom, then routed the 1/4" channel into the bottom back side of it, then glued the 3/4" pieces to the top and sides of the baffle. I'll get a better pic when I finish them and hope it'll make sense then!!
 
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mattsk8

mattsk8

Full Audioholic
Question about the xovers. In Swerd's writeup it says to use a 50 ohm resistor. I ordered the parts per the list on Swerd's write up and have 2 25 ohm resistors. My question is...

Would I hook these up so it goes- line into one resistor, then out then back into the other resistor and by the time it comes out of the second resistor I have 50 ohms of resistance?

That might seem like a really dumb question to a lot of you but there is one other option, just making sure I was doing this right. Thanks for any help!!
 
Swerd

Swerd

Audioholic Warlord
Question about the xovers. In Swerd's writeup it says to use a 50 ohm resistor. I ordered the parts per the list on Swerd's write up and have 2 25 ohm resistors. My question is...

Would I hook these up so it goes- line into one resistor, then out then back into the other resistor and by the time it comes out of the second resistor I have 50 ohms of resistance?
Hook up the two 25 ohm resistors just as you described, in series with each other. To get the total resistance of resistors in series with each other, just add up the resistance of each individual resistor.
 
mattsk8

mattsk8

Full Audioholic
Hook up the two 25 ohm resistors just as you described, in series with each other. To get the total resistance of resistors in series with each other, just add up the resistance of each individual resistor.
Thanks!! Xovers... are done :D

Curious if someone can double check these and make sure they're right before I box them in.

Tweeter xover-



Woofer xover-

 
Swerd

Swerd

Audioholic Warlord
It looks good to me.

I can't read every value printed on the components in your photos, such as for the resistors, but I trust that you read them and got them right.
 
mattsk8

mattsk8

Full Audioholic
Since I put pics of everything else, I may as well put my screw ups on here too.

Planned on putting my threaded inserts in last night but had to rewind a bit. Woofer holes are great, but anyone that reads this and uses my tweeter hole dimensions is going to be pretty frustrated w/ me :eek:.

When I originally measured out for the tweeter cutout I just took a dial caliper and measured the cutout for the tweet based on the width of the tweeter's back side. The problem is, the tweeter's are kind of square and you can't make the holes round; if you do that (which I did) it puts the 4 mounting holes 1/16" from the edge of the cutout :mad:. My fix for this was to take a rabbeting bit and rabbet out 7/16" of the tweeter hole on the back side of the baffle. Then I cut out a piece of 3/4" mdf and glued it in. Hopefully (if I have time) this evening I'll make the correct cut out in the newly glued piece that will allow for my threaded inserts.

Pic of the repair piece glued in on the backside:



And a pic of it from the front:



The bad part of all this is that I've installed these same tweeters in the Statements once already and didn't make this dumb mistake! One of those brain dead moments I have when I'm trying to hurry I guess :(. Just glad I found a way to fix it w/out having to make the entire front baffle again :D!!
 
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David LR

Junior Audioholic
Thanks for posting the screw-ups too. It illuminates possible pitfalls for other builders plus gives them good creative solutions if it does happen. Yeah, those brain dead moments, sometimes I think we all just go on auto-pilot, not realizing we, (me anyway), have to be aware & thinking all the time or I will screw up !

Those Cherry baffles are going to look really nice !
 
jinjuku

jinjuku

Moderator
For odd shape tweeters (like ribbons) I take calipers and transfer all the different measurement points to a piece of heavy construction paper.

I connect the dots. Over cut the diagram out. I then spray adhere it to 5/8's or 3/8's brown board and cut out with a fine tooth jig saw. I now have my template showing the hole and use double sided carpet tape. I then use a bearing guided up cut spiral bit to knock out the hole on the table router.
 
mattsk8

mattsk8

Full Audioholic
For odd shape tweeters (like ribbons) I take calipers and transfer all the different measurement points to a piece of heavy construction paper.

I connect the dots. Over cut the diagram out. I then spray adhere it to 5/8's or 3/8's brown board and cut out with a fine tooth jig saw. I now have my template showing the hole and use double sided carpet tape. I then use a bearing guided up cut spiral bit to knock out the hole on the table router.
Thanks for the tip, templates are the way to go for sure. I have tons of 1/4" thick plastic up at work (I work for a plastic recycling plant) that I can make them out of.
 
mattsk8

mattsk8

Full Audioholic
All fixed :). There's a lot of debate over whether to use threaded inserts or just use pan head wood screws- I'm all about the threaded inserts. From building subwoofer boxes for cars, I learned the problem w/ woodscrews in MDF is that if you pull the drivers out and put them back in more than once or twice you end up w/ screws that don't hold anymore. W/ the threaded inserts, as long as they're installed right, it's generally good forever. This is a good thing for me because I like to totally assemble the speakers so I can listen to them before the final finish; which means I put the drivers in and pull them out a couple times at least. They do take quite a bit of time to install, but to me it's worth it. If I didn't have a drill press, it would probably be different though just because getting them in straight w/ a hand drill would be tricky.

I didn't make a template for these. The cutouts were totally done by hand w/ a 1/4" bit in my router so the holes are pretty crude, but fully functional. Kind of looks like the bat signal. The holes in the statments I built are perfect so I think I'll use those to make a template when I take them apart to finish the cabinets.

Pic of the backside w/ the inserts installed:



And a pic w/ the screws finger threaded in to make sure nothing went south when I drill the holes:

 
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