Cal_Cobra
Active Member
- Joined
- Mar 19, 2024
- Messages
- 131
- Likes
- 76
Full Sehlin crossover upgrade to mod #6.
-
Welcome to ASR. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!
Hivi 3.1A DIY Speaker With Sehlin Mod Review
- Thread starter amirm
- Start date
I almost screwed up really big. Let me warn you guys and show you how to fix this and things that work that no body has tried .
Instead of iron one veneer with glue I had home depot cut melamine sheets to about 1/2" overhang on all edges. I forgot I had 2 speaker boxes so I only had enough for 1 but I tried to be clever and clamp 2 boxes vertically and also in these pictures horizontally. When I clamped two vertical boxes I put veneer only on the back side because I wanted the front where the speakers are to be last so you can't see the edges from the other veneers , melamine and the veneers faced outward and I clamped the stack with clamps. It worked. Iron on seemed like a hassle and didn't want to destroy my iron.
Next I sanded the sides with a 220 grit random orbit sander. And tried to be cool by using a large melamine for clamping the tops and bottoms of both speakers together. I put titebond 2 on the veneers and speaker box as usual , laid both speakers side by side and put the large melamine sheet on top like a sandwich and clamped for 8 hours. Woke up and all veneers were heavily warped. This means you cannot use 1 large platen board spread across more than 1 box.
Miraculous I fixed it by using a plant water atomizer spray bottle to soak the whole veneer and less than cotton setting to iron out the mess. It somehow worked! I laid out the heat fast to heat the whole veneer and then went slow to press out the wrinkles from the center outwards. The edges will wrinkle really badly but the edge glueline confirms the veneer is straight at the edges .
Also my new trim router had a bolt sticking out. It gouged lines into my veneer into the back speaker veneer. I remembered a trick by using water and the iron to steak out the gouged marks. It worked!!!
Look at these pictures
Also harbor freight has corner band clamps for $5, 1 band clamp equals 2 bar clamps. It's the cheapest way other than duct tape or regular ratchet straps to clamp these down, not shown in photos. Remove the corner brackets just use the strapping by itself
Instead of iron one veneer with glue I had home depot cut melamine sheets to about 1/2" overhang on all edges. I forgot I had 2 speaker boxes so I only had enough for 1 but I tried to be clever and clamp 2 boxes vertically and also in these pictures horizontally. When I clamped two vertical boxes I put veneer only on the back side because I wanted the front where the speakers are to be last so you can't see the edges from the other veneers , melamine and the veneers faced outward and I clamped the stack with clamps. It worked. Iron on seemed like a hassle and didn't want to destroy my iron.
Next I sanded the sides with a 220 grit random orbit sander. And tried to be cool by using a large melamine for clamping the tops and bottoms of both speakers together. I put titebond 2 on the veneers and speaker box as usual , laid both speakers side by side and put the large melamine sheet on top like a sandwich and clamped for 8 hours. Woke up and all veneers were heavily warped. This means you cannot use 1 large platen board spread across more than 1 box.
Miraculous I fixed it by using a plant water atomizer spray bottle to soak the whole veneer and less than cotton setting to iron out the mess. It somehow worked! I laid out the heat fast to heat the whole veneer and then went slow to press out the wrinkles from the center outwards. The edges will wrinkle really badly but the edge glueline confirms the veneer is straight at the edges .
Also my new trim router had a bolt sticking out. It gouged lines into my veneer into the back speaker veneer. I remembered a trick by using water and the iron to steak out the gouged marks. It worked!!!
Look at these pictures
Also harbor freight has corner band clamps for $5, 1 band clamp equals 2 bar clamps. It's the cheapest way other than duct tape or regular ratchet straps to clamp these down, not shown in photos. Remove the corner brackets just use the strapping by itself
Attachments
It's super easy to do and is the go to method because it just works. It won't destroy your iron.
Cal_Cobra
Active Member
- Joined
- Mar 19, 2024
- Messages
- 131
- Likes
- 76
Oh man that had to be a sinking moment when you first saw the veneer was warped, glad you were able to save it! So many things that can go wrong finishing the speaker cabinets (as I discovered using Minwax finish!), maybe the guys that roll-on house paint are wiser than we give them credit
Good tip on the harbor freight $5 band clamps. I was able to make one work, but there were a couple of times where a second band clamp would've made life easier.
when I looked it up it said a lot of people were buying used irons from goodwill just for this so I assumed this must destroy the iron, but you're right my iron looks fine and I've ironed almost every side even after glue up just in case
as soon as I took off the platen boards and saw it I was like, "yep I f%$#ed up" I wasn't pooping my pants yet until after I tried ironing. if that didn't work that would have sucked. After using a random orbit sander with 220 grit and gorilla wood filler, it actually sands easier than a car fender. I think spraying these with car paint after priming and sanding the primer would work. I just have to figure out how to spray a part that is 360 degrees, car parts do not require spraying the bottom and gravity will work against me. I used veneer because I'm going to mix and use stain with layers like they do in guitars for that rainbow effect. car paint only looks good on something with a lot of streamlined curves like a car, not on a square box, my guess. or at least just car paint for the front but figuring out how to do that seemed like a hassle. I know people here have done it but I'm picky, I want it to look like at least a small shop made itOh man that had to be a sinking moment when you first saw the veneer was warped, glad you were able to save it! So many things that can go wrong finishing the speaker cabinets (as I discovered using Minwax finish!), maybe the guys that roll-on house paint are wiser than we give them credit
Good tip on the harbor freight $5 band clamps. I was able to make one work, but there were a couple of times where a second band clamp would've made life easier.
Thanks, i spent some time just re connecting the drivers this morning, and it sounds as it should, ... it had to be a phase issue .. one of those things that you swear you got right but I obviously didn't, embarrassing lol
Cal_Cobra
Active Member
- Joined
- Mar 19, 2024
- Messages
- 131
- Likes
- 76
Glad you got it sorted out, at least it was an easy fix
Just wanted to show you guys something I learned. For the ribbon tweeter and bass port holes and even the main woofer a flush cut router bit is too long due to the bearing. The hole depth in the speaker box is extremely thin. I used a Dremel type tool, you want one with speed control. Get rotozip drywall bits gp8 for $12. Use an angle grinder with a grinding wheel, not cut off wheel and grind the tip off so it will touch the veneer but still have barely enough smooth section at the top to use as a guide against the round hole they already cut for the speaker. The bit will turn black and blue due to the heat, hold the bit with adjustable pliers for safety. I tested the ribbon tweeter and it will barely not fit so you still have to sand more to fit it. You could make a template out of wood or foam using the tweeter to trace the shape and super glue the sandpaper to it so you have the shape of the tweeter. I'm guessing most of not everyone else just used a razor blade to cut out that opening. Also don't touch the rotozip bit to the bottom, you can see my mistake. It won't effect the speaker though so it will be hidden
Also I was getting massive chip out from the veneer first time I tried it, thought the blade wore out, but that seemed too quick because I barely used it on the other holes. The problem was the tweeter hole is even thinner than the other holes, you have to grind the tip on the bit some more. If you get massive tear out , stop, and grind the tip some more. Luckily I was able to push the frayed edges of the tear out using cut resistant gloves and use the newly grinded bit to cut off most of the tear out splinters, picture is after I did that
Also I was getting massive chip out from the veneer first time I tried it, thought the blade wore out, but that seemed too quick because I barely used it on the other holes. The problem was the tweeter hole is even thinner than the other holes, you have to grind the tip on the bit some more. If you get massive tear out , stop, and grind the tip some more. Luckily I was able to push the frayed edges of the tear out using cut resistant gloves and use the newly grinded bit to cut off most of the tear out splinters, picture is after I did that
Attachments
Last edited:
I just checked , those are the same bits i was looking at on amazon, none are 3mm or even close, do you have a link? all of the ones searched with your keywords show a bearing or a round tip, which definitely are not 3mm, maybe 1/4" or a bit less. this one was closest but still would need shortened with angle grinder.
Whiteside Router Bits SC28C Flush Trim Bit with Solid Carbide
Last edited:
it's still too thick to fit under the tweeter hole. grinding off the bit is the only way. ok i measured it, it's 2.5mm but you would need a 2mm bit to be safe. it's just extremely thin, there's no way around it other than grinding off any bit you use. or rabbetting it from scratch again
Last edited:
You could make a circle with router the slightly snaller size than the driver hole, glue some 80 grit to it and trim around the edges with an xacto. This would give you a sanding disc to make the depth of the driver hole deeper without touching the sides, then the dado pilot bit can fit. Don't have to get the sanding disc all the way to the edge, the dado pilot bit can take off a bit with the non cutting area at the bottom, it's spinning very fast and mdf is sort of soft in this regard.
You could also just cut as close as you can leaving a lip and just sand it down till its flush. I tend to use something circular as a backer for the sand paper for that method and wrap a strip of 150 grit around it or glue it if i can (I only use 3m purple sand paper, everything else is junk imo). That method should get it flush without taking so much off with each pass that you get a noticeably uneven circle. I've had to utilize both methods above to expand and trim driver holes and the results are great. A power tool without some sort of guide for the cutting apparatus seems like it's just asking for poor results.
You could also just cut as close as you can leaving a lip and just sand it down till its flush. I tend to use something circular as a backer for the sand paper for that method and wrap a strip of 150 grit around it or glue it if i can (I only use 3m purple sand paper, everything else is junk imo). That method should get it flush without taking so much off with each pass that you get a noticeably uneven circle. I've had to utilize both methods above to expand and trim driver holes and the results are great. A power tool without some sort of guide for the cutting apparatus seems like it's just asking for poor results.
New member here! Been working on my Swan 3.1 for several years now and wanted to pass along a few tips that may be helpful. Been lurking on this subject for some time now.
Tip #1...Finishing the cabinet is a DIY weak point that people seem to struggle with. Spray paint on MDF doesn't cut it. For more professional results... At Home Depot they sell 1/4 round wood trim that is easily cut and glued to the outside edge of the cabinet. This gives a nice large round-over instead of square edges or routing. I fill in any gaps using Bondo for a perfect fit to the cabinet. Once all fitted and sanded smooth with no gaps spray paint the face with FLAT black paint. I used Rustoleum high performance enamel #7578. 3 or 4 light coats yielded a perfect flat finish. Make sure to spray on the speaker openings as well.
#2.... At "Floor & Decor' they sell Pre-finished wood flooring. REAL wood veneer glued to a 3/8" plywood plank. Loads of great color choices of stained and professionally clear coated wood flooring. Just cut/fit and install!! No staining and no finishing required. My daughter had left over "African Tiger Wood" she had installed on her kitchen floor. It was beautiful so I used that as an experiment.
Important... the thickness of the plywood plank is 3/8" thick so it mates up flush with the attached round over when you install the wood on the sides of the cabinet. I used a tube of urethane glue out of a caulking gun. It a thick glue that allows for some slight height adjustments. Very strong. I also ripped the 6" planks into more manageable 3" strips. Take each piece and fit it perfectly.
This requires using a thin blade on a table saw to get clean cuts at a 45 degree angle at the corners where the side and the top edge meet. Take your time and dry fit each piece so it fit's properly BEFORE gluing. Start the first pieces at the 1/4 round and work towards the rear. Fit the last piece on the back edge and you're done!
This accomplishes three important things... 1. Edge diffraction eliminated rounded edges, 2. cabinet is more ridged and less resonate due to external bracing of the plywood and glue. 3. perfect professional stained and clear coated finish. Looks great even with the grills on with all black front.
Lastly install the speaker drivers. This was finished in half a day. Hope this helps!!
Tip #1...Finishing the cabinet is a DIY weak point that people seem to struggle with. Spray paint on MDF doesn't cut it. For more professional results... At Home Depot they sell 1/4 round wood trim that is easily cut and glued to the outside edge of the cabinet. This gives a nice large round-over instead of square edges or routing. I fill in any gaps using Bondo for a perfect fit to the cabinet. Once all fitted and sanded smooth with no gaps spray paint the face with FLAT black paint. I used Rustoleum high performance enamel #7578. 3 or 4 light coats yielded a perfect flat finish. Make sure to spray on the speaker openings as well.
#2.... At "Floor & Decor' they sell Pre-finished wood flooring. REAL wood veneer glued to a 3/8" plywood plank. Loads of great color choices of stained and professionally clear coated wood flooring. Just cut/fit and install!! No staining and no finishing required. My daughter had left over "African Tiger Wood" she had installed on her kitchen floor. It was beautiful so I used that as an experiment.
Important... the thickness of the plywood plank is 3/8" thick so it mates up flush with the attached round over when you install the wood on the sides of the cabinet. I used a tube of urethane glue out of a caulking gun. It a thick glue that allows for some slight height adjustments. Very strong. I also ripped the 6" planks into more manageable 3" strips. Take each piece and fit it perfectly.
This requires using a thin blade on a table saw to get clean cuts at a 45 degree angle at the corners where the side and the top edge meet. Take your time and dry fit each piece so it fit's properly BEFORE gluing. Start the first pieces at the 1/4 round and work towards the rear. Fit the last piece on the back edge and you're done!
This accomplishes three important things... 1. Edge diffraction eliminated rounded edges, 2. cabinet is more ridged and less resonate due to external bracing of the plywood and glue. 3. perfect professional stained and clear coated finish. Looks great even with the grills on with all black front.
Lastly install the speaker drivers. This was finished in half a day. Hope this helps!!
One other point of interest is the "perfect cross-over' modification I have tinkered with for a awhile now.
Standard crossover the tweeter was way too bright. I did the suggested 5.6 ohm resistor across the tweeter and that worked perfectly. Sharpness was gone. Done deal.
I went ahead and did the additional mods to the midrange crossover and found that I actually preferred the sound in stock form. I felt that there was a LOSS of resolution that I had enjoyed in the original voice of the midrange. So, I un-did the modification and went back to the stock crossover. Bingo the sound was again crystal clear. Much preferred. So all I ended up with was the easy tweeter mod of 5.6 ohm resistor.
I realize that the speaker measures better with the 'crossover mod' but it just didn't sound as good. A lot of people went straight into this modification without ever listening to the stock sound so they don't know what they are missing. The midrange is brilliant all on its own with stock crossover and I won't be going back. This of course is dependent on the up-stream gear your using. These speakers are amazing if you tweak them just a little. They don't need a major overhaul to sound their best. IMHO
Cheers!
Standard crossover the tweeter was way too bright. I did the suggested 5.6 ohm resistor across the tweeter and that worked perfectly. Sharpness was gone. Done deal.
I went ahead and did the additional mods to the midrange crossover and found that I actually preferred the sound in stock form. I felt that there was a LOSS of resolution that I had enjoyed in the original voice of the midrange. So, I un-did the modification and went back to the stock crossover. Bingo the sound was again crystal clear. Much preferred. So all I ended up with was the easy tweeter mod of 5.6 ohm resistor.
I realize that the speaker measures better with the 'crossover mod' but it just didn't sound as good. A lot of people went straight into this modification without ever listening to the stock sound so they don't know what they are missing. The midrange is brilliant all on its own with stock crossover and I won't be going back. This of course is dependent on the up-stream gear your using. These speakers are amazing if you tweak them just a little. They don't need a major overhaul to sound their best. IMHO
Cheers!
Edge round overs of that size don't eliminate edge diffraction, mostly lowers the frequency at which it occurs. Fairly large round overs are needed to mostly fully mitigate it in the mid and tweeter ranges. Think kii stuff or grimm ls1.
HighFutility
Active Member
- Joined
- May 8, 2022
- Messages
- 218
- Likes
- 191
I just got myself a Wiim Amp. Can I enter these into the 10 band peq ? This only uses 9.
Hello,
Can someone explain to me why are my resoults different in XSIM compared to MOD 5 graph?
I got my FRD and ZMA files with SPLtrace or FPGraph tracer, put coil rezistance in, Z offset mesured with UMIK-1,...
What am I doing it wrong?
Can someone explain to me why are my resoults different in XSIM compared to MOD 5 graph?
I got my FRD and ZMA files with SPLtrace or FPGraph tracer, put coil rezistance in, Z offset mesured with UMIK-1,...
What am I doing it wrong?
Making traces implies you're using manufacturer data, but then you stated you measured so I'm a little confused there.
If you're using manufacturer data (which it looks like you are, at least for the woofer) you need to apply diffraction sim which you can do in Virtuixcad. Honestly time to ditch xsim and just use vcad.
Similar threads
