First time OB builder

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Just finished my latest incarnation of the test baffle...
Immediately it sound much more open and natural even without touching the crossover from its previous setting.

Will fire up the cross software in a minute to see what changes it makes but for now here a pic of the new stand.
 

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Holy Dooley...its a good thing these speakers don't put out because my partner would be in trouble ;-) think I'm in love!

Made a few crude adjustments to the crossover and sat back and listened to some Pink Floyd. Listen to High Hopes with my eyes closed I nearly fell asleep I was so lost in the music.

I'm nearly scared to build the second speaker in case I ruin perfection. Ok so its not perfect yet, but it well on its way. I think it would be a close call between these and some $55k Gryphon Atlantis speakers I listen to a while back they sound that good.
 
Thanks, pretty hard to go wrong as they are all great sounding drivers, but there are certain combos that definitely sound better than others. I can see why StigErik is a fan of the baffless setup they sound great like that.

Still think there are some gains to be had in the bass department but no giant leaps, more along the lines of refinement. There are times when I think there is just the right balance of bass and other times when I think it needs to just go a bit lower.

Really glad I listened to the advice that OB is great for bass. It is in a whole different league to small drivers in a box. Thanks to everyone that persevered with me to get to this point.
 
Yes if you go back several pages you will see plans for a H frame are already afoot.
When I saw your assorted drivers on that big OB, I had feared for a minute that you might have lost control :p
But you could have a sort of inner radar leading you back on the way. Last remark: Forget about that funny "horn loading" association in connection with a woofer H frame. You might gain better looks - but nothing more. ;)
 
I have mostly abondoned the idea of fancy cabinets for now, for that very reason, it might be mostly cosmetic, and I need to focus on what makes a difference to performance.

In my extensive baffle making experience (all of 5 minutes now :)) I have come to the conclusion that virtually any thing that helps the bass will also hinder the sound.

For example I put the cardboard box that the 18" came in up against the front of the baffle (both ends taped back) to form a crude square baffle extension, and there was an audible increase in bass (SPL) and what appeared to be slighly lower in frequency, but at the same time it did seem to every so slightly colour the sound.

So I really dont want to add anything that wont help the end result. I do plan to vere slightly off the beaten path with the H frame, in as much as I plan not to mount the driver to the cabinet.

I was reading on the Linkwitz website about driver mounting Issues in speaker design - 2 and it gave me an idea, if I isolate the driver from the cabinet, I can then mount the tweeter and mids to the H frame without it receiving vibrations from the woofer.

Allowing me to kill two birds with one stone... improve the sound of the woofer and make mounting of the tweeter - mids easier.

Still trying to work out what to do with the 10", it really needs to be there but where to fit it without disturbing the balance...
 

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Sitting here listening to some music I cant help but feel that the two 8ohm 4.5" 12MUs are a bit small in cone size to produce a really balanced mid vocals.

Dont get me wrong the sound sweet as, but listening to the voices I cant help but wonder if they are slightly too high pitched to give a warm mid sound, tending to think they sound a bit too clinical.

I am also thinking about the 10" drivers I want to replace, and I keep comming back to running some 6.5" Illuminator mid woofers.

Basically that would be a similar setup to my Cremonas (1 x tweeter, 1 x 4-5" mid, 2 x 6.5" mid woofers), except I would be using an 18" woofer below the mid woofers and would want to run 4 x 4ohm 6.5" drivers (series - parrallel) to come back to 4ohm.

Just doing the Sd numbers:
1 x dipole tweeter = 22cm2
1 x 12MU = 58cm2
2 x 12MUs = 116cm2 (58cm2 each)
1 x 10" = 320cm2
4 x 6.5" = 616cm2 (154cm2 each)
2 x 10" = 640cm2 (320cms each)
1 x 18" = 1194cm2

Looking at the ScanSpeak 18WU-4741 data sheet I could cross over to the mid woofers anywhere from 2500Hz down. Giving more warmth the the mid vocals and tight punchy bass.
 

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Agree for a driver of their size they do a pretty decent job, the only thing they lack is cone size... If you play the same frequency through a large cone and a smaller cone, they both may play the same tone at the same SPL but the tonal characteristics of the drivers sound completely different.

I think that is in part what I like about the TC Sounds 18" it delivers a good amount of tight bass, but it sound like it does it effortlessly.

Probably similar to having a huge cubic inch big block making a lazy 500HP and having a highly tuned turbo 4 cylinder making the same 500HP. Both produce the same final number but there is a world of difference in the way they do it, and the way they sound.

Same goes for the mids... I plan to cross over to 4 x 18WUs and let them carry some of the vocal duties to make it less squeaky and a bit warmer / fuller sounding in the vocals.

For the rear channels it is quite possible the 12MUs might be all I use for mid through to bass in the form of a 2 way...

We had a HiFi show here in Sydney over last weekend and I suspected the 12MUs were not quite right in the vocal department, after listening to quite a number of different speakers, I come to realise my gut feeling was right.

The 12MUs will definately still have there place, as one system I listened to went from some SS 2904 tweeters straight to some 18WUs and it sounded like it was missing something quite sweet the 12MU provide in between.
 
Hi Silent Screamer,

I just found your very interesting project and I also own a Groundsound DCN28.

I like to share some expeeriences, hopefully you too.

My actual system consists of:

CD Player REGA Saturn, DCN28 (special front plate with Sorensen instead of Groundsound), 8x Audreal MNE 8800 mono amps.

Speakers: DIY FAST system (until now, I am planning to try out a B&G Neo3 (already bougth) as a super high tweeter. Fullrange is a TangBand W8 1772 in a controlled leakage box and subs are 4x Emminence 18" in two ripole boxes. The bass is unbelievable deep and dry, lets say pure.

My basic problem is the correct measuring and usage of the XOver software. In the beginning I was happy because everything seemed to be so easy. After some month of usage I found out, that the few pages manual of the Xover software doens´t explain everything well. E. g. how to use the TWO, how to use the multiwin, duowin, ambiwin function correctly, how the phase can be estimated correctly and so on. I found out some tricks and different procedures how to influence the eq´s and how to set up the final xover files. But i am still not convinced about the correct usage. Further more how do you measure? Distance to the chassis? On axis of the mid´s, what about the others? Do you also measure at the listening position? Windowing? I have 1000 questiosn, especially how to combine the - let´s say - best known measuring practice with the usage of the DCN...

Best regards from Germany...

8m72j8cp.jpg


@Rudolf, best regards!
 
Very nice looking Peter! I like how you set the bamboo plywood on a 45deg angle. I would certainly recommend using the Neo3 in place of the high range that the TB develops. I bought the 1808 version to very in my project and found the top end lacking to say the least compared to a good tweeter.

If you've got pictures of the build process, a new thread that you could link to this on would be very nice. Thanks for sharing.

Greg
 
Hi Peter... Looks good. First thing I would tell you is to contact Robert at Ground Sound he has been super keen to help out with any questions I've had, he may be able to help out with some suplimental instructions.

I still have my trainer wheels on, so I haven't progressed with the learning of the software too much, just enough to put together a very basic 4 way crossover, no real tricky stuff.

I know it is capable of much more than I have used so far, but I haven't got to the stage where I am ready to start optimising the croosover. Once I have all the drivers sorted out and some proper mountings sorted out, I will try to learn a lot more, but as you say it allows you to do some basic stuff quite easily.

Like Greg I would be keen to see a bit more of your build especially the subs. Just out of curiousity what is your opinion of the DCN28? this is my first active but to me I am very happy with mine.

Might take me a while to respond currently on a 6000klm / few week holiday.
 
Hi again,

first of all my real name is not Peter ;) like it is common in such a forum.

Thank ´s for your interest. There is a German forum where I described the build up in detail. I hope the link is allowed here and it works. Unfortunately it is written in German, but there are a lot of pictures.

"fortytwo" Ripol & KU & TL16H - Visaton Diskussionsforum

Yes, Robert is always very kind and willing to help, I know him very well. But his knowledge of the software is limitited due to the fact that it is from a sub supplier and he focusses on the hardware.

I will wait until you start to dig deeper into the details and I will be here as soon as you like to talk about it. Maybe we can learn from each other.

Best regards
Karsten
 
I will wait until you start to dig deeper into the details and I will be here as soon as you like to talk about it. Maybe we can learn from each other.

Best regards
Karsten

Hi Karsten, yes that sounds like a very good idea. The help file is somewhat limited and perhaps between us we can get a bit more out of the software.

I have just this very minute ordered another 10 drivers for my project (18WU/4741T00). four will turn up next week and the other six are back ordered.

I plan to run 4 per side in a series - parallel configuration. Then that is it for now, I won't buy any more drivers until I have proper measurements and some half decent speaker holders made.

I haven't decided if I want to build a 5.1-2 system or a 7.1-2 system. I guess I will make that decision once I see how many drivers are left from the 10 x 12MUs and the 10 x 18WUs.

Edit:
Over estimated the mileage for the trip... only did 5832klms :)
 
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