AudioCircle
Industry Circles => GR Research => Topic started by: rockdrummer on 7 Jul 2019, 02:18 pm
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Hi everyone. I love seeing build threads, and also sharing to get advice too. I've built a few GR kits, and this is my second go-round with epoxy. I used epoxy on the outside of my H-frames.
Got the kit from Danny and a sheet of no-rez, and it arrive packed great. The flat pack from Jay was also packed perfectly. At this point, I'm glued up, and a first coat of Raka 127/non-blushing 350 epoxy went on last night.
(https://www.audiocircle.com/image.php?id=196319)
(https://www.audiocircle.com/image.php?id=196318)
(https://www.audiocircle.com/image.php?id=196321)
(https://www.audiocircle.com/image.php?id=196322)
I see some runs in it, so I need to be a bit more careful. A little extra sanding in my future. Should go quicker than the h frames though!
I will be spraying over last and I may put grill cloth between the drivers and the front baffle.
I just thought about this, after I get dry enough, I need to test fit the drivers to make sure I don't thicken up the back recesses too much and make the neo drivers too snug to fit. Thinking out loud.
See you when I get more done.
Ben
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Nice build!
Yes, the opening for the GR-NEO3 is tight, so do a test fit before putting more finish in the area.
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Looking forward to seeing more in this thread. :thumb:
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Looks good Ben :thumb:
As rich mentioned, the opening around the tweeter is tight, on this first run of baffles I had to scrape out every tweeter recess out as they were designed to fit the original Neo3 PDr ... Danny's came in just slightly larger . All subsequent runs will have a slightly larger recess for the tweeter so no more scraping .... makes me happy :green:
jay
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Hi all, back with an update. 4 coats of epoxy on thr cabinets. Here are a few images.
Sanding off the small runs down the face, not hard, but a bit time consuming.
(https://www.audiocircle.com/image.php?id=196615)
The face comes out so smooth and easy, the waveguides, however, I knew they would be more work.
(https://www.audiocircle.com/image.php?id=196611)
There was much more care taken when sanding out the corners of the waveguides. I used 150 grit where on flat surfaces I used 100 to start.
(https://www.audiocircle.com/image.php?id=196612)
(https://www.audiocircle.com/image.php?id=196613)
I think I went through the epoxy into the medex baffle ever so slightly, on the spine between the neo 3 and 10. So I touched that up and I am pretty sure I have stayed on the epoxy this time.
I had that issue on the rounded bases of my h frames. This time I made sure to just get mostly smooth so I would leave enough for the epoxy to layer.
Once I finish the second baffle, I will start sanding 220 and then 320. I will also post pics of the crossover boards when I get the final coat on.
Hey Jay, the drivers fit just right in the back of the baffle, so thanks for your work scraping them out!
More later.
Ben
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Looking good Ben :thumb:
2nd round of baffles should be available next week and no more sanding / scraping !!
jay
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Hi again. Just wanted to put a couple more shots up of the baffle, and hopefully some incentive for others who may be thinking epoxy isn't worth the effort or too much work. I'm not much of a "woodwork craftsman" but I like to dabble and this was easy, after some research and prep, with some awesome results.
(https://www.audiocircle.com/image.php?id=196650)
(https://www.audiocircle.com/image.php?id=196651)
(https://www.audiocircle.com/image.php?id=196652)
(https://www.audiocircle.com/image.php?id=196653)
Those seams are perfectly smooth and any light discoloration is wood glue underneath.
Ben
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Hi, curing question. I emailed Raka last week but they didn't respond. How long should I let the last coat of epoxy cure before spray painting? I read online that 72 hours was fine, but I had 1 week in the back of my mind.
I'm out of town, and was hoping to get the 2nd cabinet sanded when I get back. If I need to put another coat on, then I'm pushed back again. Oh well.
Thanks
Ben
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Hi, curing question. I emailed Raka last week but they didn't respond. How long should I let the last coat of epoxy cure before spray painting? I read online that 72 hours was fine, but I had 1 week in the back of my mind.
I'm out of town, and was hoping to get the 2nd cabinet sanded when I get back. If I need to put another coat on, then I'm pushed back again. Oh well.
Thanks
Ben
I don't know about Raka but I normally let West Systems epoxy cure 24 hours before sanding then start applying either primer/sealer or veneer the next day. But then I sand most of the epoxy off so there is not much of a build. I would guess the thicker the epoxy, the longer it needs to cure.
Mike
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Thanks , Mike.
I will probably be able to finish up my crossover boards first, then paint those a black. I'm excited to get working on those. That will give me any time to let a possible last coat cure up on the second cabinet.
I get back from Washington D.C. with my family late Monday, so Tuesday morning I hope to get into the garage and sand till my heart's content!
Ben
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Hi there. I will be posting more pics in an update soon, but one quick neo 3 question.
Anyone know if the black yarn goes on the outside chambers of the front AND back of the driver?
Thanks.
Ben
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Ben,
The yarn goes in the outside chambers only on the front of the GR-NEO3 tweeters.
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Thanks Hal.
Ben
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Just got my pair of Super Mini baffles built, drivers and wiring installed.
(https://www.audiocircle.com/image.php?id=197195)
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Awesome! Bet that combo of a Gibson SG and Laney/Marshall sounds good too!
Ben
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Yes it does! :D
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My yarn's in the back. I guess I need to make a change.
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Almost finished :cry:
I'm sure I'm not the only one who gets sad when the building process is done. Love working on things like this.
Finished sanding, got to painting. I'm not good at spray painting. I always end up with inconsistent finishes. I think I'm moving too fast and I don't get good coverage with passes that are probably too far apart. Anyway.
(https://www.audiocircle.com/image.php?id=197398)
Crossover boards
(https://www.audiocircle.com/image.php?id=197399)
I didn't use gaskets on the neo 10. That way, the driver rests up against the baffle with very little gap between it and the waveguide. I used a big drill bit by hand to open up spots where rivets protrude.
(https://www.audiocircle.com/image.php?id=197400)
(https://www.audiocircle.com/image.php?id=197401)
Finished crossovers. I made them as copies to keep wiring simple for me.
(https://www.audiocircle.com/image.php?id=197402)
(https://www.audiocircle.com/image.php?id=197403)
Ordered the miflex bypass caps from Danny, and a replacement for a tweeter that didn't work.
My phone camera is cloudy, so I'm hoping to get good clean pictures of the finish when I'm up and running.
Thanks
Ben
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Almost finished :cry:
I'm sure I'm not the only one who gets sad when the building process is done. Love working on things like this.
Finished sanding, got to painting. I'm not good at spray painting. I always end up with inconsistent finishes. I think I'm moving too fast and I don't get good coverage with passes that are probably too far apart. Anyway.
You and me both. I spent a good 4 months trying to teach myself how to spray paint to get consistent results before I even thought about attempting to spray paint my Super 7s. I learned a lot from this guy https://www.youtube.com/watch?v=qB_MtpaMYaY&t=397s (https://www.youtube.com/watch?v=qB_MtpaMYaY&t=397s) but I am convinced I'll never be good at it.
I found a routine that works for me though - it just uses a ton of paint. I spray the first coat on which typically for me is either uneven, has rough spots and runs or the worst of all, tiger striping - I have learned to minimize all of these though by doing multiple light coats. After 48 hours I then sand the uneven and rough spots in the first coat with 600 grit - 400 for paint runs/drips. Then I paint again but this time I don't have to spray on nearly as much which means it is impossible to make as many mistakes as I made in the first coat. I sand any imperfections out again and spray an even lighter coat. Repeat until I am broke from buying spray cans or I get the finish I want. Its definitely not professional advice lol.
I have also found that I have an easier time with "wetter" spray paints like Krylon as opposed to Rustoleum which tends to go on drier. I find rustoleum to be superior to Krylon but every single time I have tried to use it I get heavy tiger striping because again, I suck at this. Krylon gives me a much larger margin of error I just have to watch for runs. Krylon is so wet that I can sometimes wipe runs off and quickly repaint with no issues. So I keep a microfiber cloth handy when I paint.
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In my experience painting plastic models, this first coat goes on thin. Your mileage may vary.
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:D looks great,, X-over work is very neatly done. Nice project. :D
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Jay / Danny,
Not intending to crap on this thread, but...given the challenges of a DIY'er to apply paint worthy of this speaker, have you thought about going all "Vandersteen" on this design, i.e. putting a couple of dowels in the rear corners, CNC'ing some nice hardwood caps for the tops and bottoms, and wrapping the speaker in fabric? I could see offering just enough fabric to staple the ends to the dowels, allowing for a twist or 2 to cover the staples and pull taught (the back would remain open for access to the drivers and crossovers). The caps would have holes for the dowels, grooves to seat the wings, and a narrow groove for the edge of the fabric to fit into. Depending on the hardwood used, a simple tung oil finish may be all that is necessary.
Just some Friday afternoon thoughts.
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Ben
go easy on yourself man. doing a great job. Always remember, lot's of light coats using a spary bomb is always gong to result in better finish. Block sanding between coats is the way to go... over and over.. Will eventually result
in a gorgeous finish.
jay
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Hi there. I'm back, and here is the embarrassing story I have.
I got the replacement driver from Danny, got it wired up and it worked great. Soldered in the bypass caps and hooked up my stereomour from bottlehead and it sounded great. Not lots of headroom (3.5 watts).
So I tried the bottlehead battery powered quickie preamp into the Folsom 7297 chip amp. Sounded great, but before the song was over, popping, crackling and lots of intermittent fuzz started. I tried swapping everything I could and it was still there. No idea how I was going to fix the gear. Turns out it was the directv box on the shelf below it. Took too many days to figure that out.
Love the sound, even in my untreated room.
I was going to put grill cloth over the drivers but behind the baffle, just didn't fit.
(https://www.audiocircle.com/image.php?id=197789)
(https://www.audiocircle.com/image.php?id=197790)
(https://www.audiocircle.com/image.php?id=197791)
(https://www.audiocircle.com/image.php?id=197793)
(https://www.audiocircle.com/image.php?id=197794)
(https://www.audiocircle.com/image.php?id=197792)
Now I am looking for best treatments to make and install to improve my imaging.
Thanks for looking and when I get a better handle on the sound to give a little review, I will.
Ben
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They look really good!
I find the wall behind them is really good with diffusion panels. Has worked really well in two different rooms.
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^^^^^^^^without a doubt that made a huge difference in our room.
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Hi everyone, I have a spike question.
Has anyone used parts express spikes for under servo h frame subs? I have been testing placement for quite a while, and there's lots of vibration reaching up to the top of my super mini's. I knew I would be needing spikes on this carpet, but i couldn't find weight ratings for the spikes on parts express. There are Dayton Audio outriggers which I would certainly entertain, but wasn't sure the look was what I wanted. I did want to keep cost down, but if the heavy subs with a topper on them needs a substantial spike, I don't know what it is.
I was hoping to stay under $100 for 8 spikes.
Thanks for any info you all have.
Ben
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Hi everyone, I have a spike question.
Has anyone used parts express spikes for under servo h frame subs? I have been testing placement for quite a while, and there's lots of vibration reaching up to the top of my super mini's. I knew I would be needing spikes on this carpet, but i couldn't find weight ratings for the spikes on parts express. There are Dayton Audio outriggers which I would certainly entertain, but wasn't sure the look was what I wanted. I did want to keep cost down, but if the heavy subs with a topper on them needs a substantial spike, I don't know what it is.
I was hoping to stay under $100 for 8 spikes.
Thanks for any info you all have.
Ben
I noticed Hal was using isolation under the Mini to isolate from base. Maybe he will chime in.
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Here is an alternative from Danny:
http://gr-research.com/floorspikes-chromesetof4.aspx
I use HVAC vibration blocks between the planar baffle and subs.
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I had those spikes from Danny on my super v kit. I was hoping to stay shorter.
Thanks for the quick responses!
Ben
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I don’t have spikes under the H-frames but I have Herbie’s Fat Dots between the monitor and H-Frame
Mike
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Might wanna give a couple sheets of Sorbathane a try too (betwen Super Mini's and Sub tops)
I've used it between the Encores and subs, Otica MtM's & subs and now a nice thick layer between my crossovers and sub tops on the Super7's.
It also will totally stick your speakers in place
jay
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I had those spikes from Danny on my super v kit. I was hoping to stay shorter.
Thanks for the quick responses!
Ben
Hey rockdrummer,
So, what's the verdict? How do the Super Minis integrate with the OB subs? Do you feel that they may be a bit thin in the mid-bass?
I am very curious about your experience, because I am thinking of a similar setup for myself.
Thanks
Panos
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Hey, I wish i had the ears and expertise/experience to answer that. i would have to say I'm loving them. They have around 60-80 hours on them. I've not had as much listening as I'd like, and i don't run them for long periods to burn them in.
I love the openness and the spacial soundstage. The clarity of the particular instruments and vocal details is breathtaking.
The comparison between models with and without that mid-bass heftiness is not something I can speak to. I wish i could. If some of you sat in my listening room, and i really wish it could happen!!!, I bet there could be some really good insight on my room/system. I don't have a good ear for what my rig is missing. Just what i hear now compared to before.
The subs sound good with the super minis. I LOVE the servo subs. For example, they reveal the type of pedal, and even tuning of the bass drum...Which I had not heard in other subs I have used. Top notch integration, I'm just doing the basics of levels. I feel I have some to learn about sub integration. I will be eventually building stands for the minis. The sub sounds travel up the baffle of the tops. The subs are spiked and they don't wiggle, but I can easily feel them through the tops when they play.
I think it would be fun to hear them with the servo stands that are being planned, but I don't see that happening for me due to funding.
An upgrade for me would have to be quite a big deal, because I love this set up, room treatments to come.
Sorry I can't be more help about specific details about the presence of sound quality.
Ben