Yes it's possible, but you have to keep the same waveguide design. However this speaker is designed as free space design and to be kept away from near by walls and reflective surfaces like the desk. For desktop speaker you're better of buying set of monitors specifically designed to stand on top the desk as they have specific switchable filters to counteract the boost in lower frequency band caused desktop placement.
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Revel M105 Copy DIY build
- Thread starter McFly
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Would some kind of DSP help with that? I know close to nothing about speakers, but after trying "speaker sound" with MR4's, headphones just sound wrong to me now, so I'm looking for better speakers.
I'm looking at KH80s as well, but I'm not too fond of their appearance.
It is normal to use some form of DSP/EQ to correct the frequency response below 400-500Hz. At low frequencies the room has a huge influence on the sound, and even with acoustic treatment + multiple subwoofers it cannot be fully mitigated.
I would rather look for min 5" midwoofer like KH120 just to have a bit more meat in the bass and some spare SPL before running into distotions. Neumann makes good 's..t', and I wouldn't be surprised that the strange look is dictated by actual acoustics. My daily driver headphones are Sennheiser HD650 and 58X with solderdude mod, open backs, and most closed backs just sound very wrong.
www.audiosciencereview.com
Also check Erin's Corner as he does a lot of mini monitor reviews.
Neumann KH120 II Monitor Review
This is a review, detailed measurements and listening tests/EQ of Neumann KH120 MKII DSP active monitor (speaker). It is on kind loan from the company and costs US $999 each. I love the form factor for desktop use. It is not too deep or unwieldly as some larger configurations can be: Back...
www.audiosciencereview.com
Also check Erin's Corner as he does a lot of mini monitor reviews.
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somebodyelse
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That's how most of the monitors do it - the switches on the back select the EQ to be applied by DSP to suit different mounting locations like desk, wall or free space.
Jopldangla
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I had some Morel ST1108 tweeters and tried to build these Revel M105 Copies.
A few differences. Front Baffle thickness is 1.5"thk, all other walls are 1"thk. Interior size of enclosure is the same as this design (the outside dimensions grew to support).
Here is the X-over vs. Speaker 1 and Speaker 2.
Here is Speaker 1
Here is Speaker 2
and Here is the X-Over
Thanks to @McFly for this project. and thanks to @augerpro for helping me with a better waveguide than my sad attempt.
The speakers have been a lot of fun to build and even more fun to listen to so far.
A few differences. Front Baffle thickness is 1.5"thk, all other walls are 1"thk. Interior size of enclosure is the same as this design (the outside dimensions grew to support).
Here is the X-over vs. Speaker 1 and Speaker 2.
Here is Speaker 1
Here is Speaker 2
and Here is the X-Over
Thanks to @McFly for this project. and thanks to @augerpro for helping me with a better waveguide than my sad attempt.
The speakers have been a lot of fun to build and even more fun to listen to so far.
4dB difference in tweeter level between spkr1 and spkr2 ? These Morel tweeters aren't exactly cheap and I would expect them to track each other within 1dB tolerance. Maybe you wired the x-o differently in the second sample, or the dome doesn't sit in the waveguide exactly the same way as the first sample. Anyway there is something strange going on and I very rarely see tweeters sticking out more than 1.5dB from each other, even the very cheap ones. Maybe one of the ST1108 is damaged.
Jopldangla
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When I collected measurements of just the tweeters (no crossover network) i did observe a difference in the two. I think I probably need to make some adjustments to the LPAD circuit. it doesn't bother me currently, my receiver/amplifier (Marantz SR6008 made some adjustments Audyssey). When I pull the speaker apart to paint/finish, I will consider changing the resistors.
In this picture I was comparing both tweeters in the stock mounting plate and also in the waveguide. Red/Green would be the two in the waveguide and blue/orange would be in standard plates. looks to be a 4db difference.
With that said.. I am still considering breaking the speaker down, selling the parts, and purchasing a pair of used bookshelf speakers. (maybe some KEF R3.. Someone is selling a pair for $1k on FB marketplace...who knows if its real or not).
Yeah, this is what I was afraid of. For $600 per pair this is unacceptable. My cheap SB Acoustics tweeters are within 1dB. If the Morels were sold as matching pair, then I would expect them to measure no worse than other manufacturers (old Vifa, Scan, Focal). I suspect that the lower SPL unit has some kind of defect, the lead wire partially broken or something. Too bad as people rate them very highly. There used to be replacement dome available for this Morel driver from Solen, Madisound and others. It would worthwhile to check the availability, I would even contact Morel directly.
P.S. don't run frequency sweep of tweeters from less than 200Hz/2.83V. Often people damage them because of inadequate protection below Fs and too high drive level - some drivers are more prone to damage than others.
willys-hifi.com
Supposedly still available in some places
P.S. don't run frequency sweep of tweeters from less than 200Hz/2.83V. Often people damage them because of inadequate protection below Fs and too high drive level - some drivers are more prone to damage than others.
Morel R32/33 Dome Tweeter Repair Kit
Morel R32/33 is a genuine replacement dome and voice coil for tweeter models MDT-32, MDT-33, CAT 328, CAT 338, ET 338, ST 1048, ST 1108, ST 1308.
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Jopldangla
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Start by measuring voice coil resistance with DMM, then do impedance sweep, compare the two. But that may give no indication of damage, because often the voltage and current are too low to detect the problem. Basically you would have to disassemble the tweeter and inspect the wiring very closely. Often the thin lead wires between voice coil and connectors are damaged if someone applied too much juice - they still conduct but at reduced rate. Also I would check soldering quality at the connectors just in case.
Changing the dome assemble is usually very easy, most of them are self centering.
Changing the dome assemble is usually very easy, most of them are self centering.
I just started this build and am pretty much done with the cabinets, just need to glue them together. I had a few questions:
- Currently my front panel is only 18mm MDF -- should I just go for a smaller round-over, or would it be beneficial to glue a second 18mm MDF panel onto the front panel?
- This is going to be my first set up speakers (DIY or otherwise), so I'm looking for a budget friendly amp and DAC to power them -- any recommendations for under 300$ total? I am currently between the SMSL SU-1 + Fosi V3 combo, or just simply a the Wiim Amp.
- How is the waveguide attached to the tweeter? Is it really just a brace and two threads?
- How did you continue to work on the speaker after you glue the box shut? For example if I put it all together and then find out something in the XO needs to be swapped, would there be any way to do it? I was thinking about making the back panel removable but that would make a veneer more impractical.
- What would you recommend for insulating the inside? I was looking at the Sonic Barrier 1" acoustic foam and was wondering if that was a good choice
ChargedCapacitor
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1. Definitely go for a second panel to get a larger round-over.
3. Yes, a brace and threads. You will have to take the front guide off the tweeter, and the diaphragm will loosely sit on the driver, and a bracket will need to be made and installed. I 3d printed mine.
4. Design your speaker so it can be worked on after being assembled, usually by taking out the woofer.
5. for the most part poly fill is all you need, but you can line the inside with kilmat, then adhere cheap melamine foam pads on the walls, then stuff lightly with polyfil.
1. Will the 3/4 inch offset on the drivers due to the second panel lead to any negative audio differences? Or will the difference from the original design (36mm vs 30mm) mean it's basically negligible?
My XO board doesn't quite fit through the woofer hole, and it'd be a huge pain to refit to another panel. Are they normally supposed to?
ChargedCapacitor
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Yes, the offset will effect it. Mount drivers flush to the baffles, and get a new xover board or modify the one you have. Otherwise, you will need to put the xover on the back of the speaker in a second chamber.
Just ran across this thread today.. Anyways I was thinking that the waveguide design can probably be modified for better FDM printing by splitting up this print and using heated inserts.. This will create a seam though, but it might also make it do you can directly screw the driver into the wave guide rather than using the peg and mount option. Either way I will play around with the step today and throw some prints to the printer and see how it goes.
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You can always mount the X-O in separate box, actually it's preferred to have the over parts away from magnets and vibrations. On top it's easier to do fine tunning and voicing with X-O out of the box.
As for offset in Z axis between tweeter and woofer, it changes the phase relation therefore the frequency response will change. 5mm can be ignored but anything over that usually adds to much phase relation difference. Most of the time we want tweeter dome behind flat faceplate/baffle to make the phase relation easier to align/compensate in crossover design, so we don't have hole in freq. resp. around crossover above the tweeter axis. Erin at Erin's Corner shows at in his reviews.
okay threw the waveguide in cad today and took a good look at it.. Separated the top and bottom to allow for easy printing on a FDM printer and some heated inserts too allow for a secure fitment afterwords. Also replace the rear holes used for the mounting bracket with heated inserts for better threading and re-use. Printing a test one now will report how it comes out although I do not have the tweeter yet..
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