Site Links
Howdy, Stranger!
It looks like you're new here. If you want to get involved, click one of these buttons!
Quick Links
Categories
In this Discussion
Who's Online (1)
- rjj45 8:30AM
Tweeter for a Peerless 830855 MTM?
Been interested to try an MTM, but figured I'd start small. Picked up some of the 830855 4" woofers. Trying to decide on a tweeter to pair with em. The 830855 really does seem to identify as a 6.5" as Ben has stated. Judging by the factory response graph it wants crossed below 3khz.
I've got some DX20BF00s that I tossed on an order since they were on sale.. But seems that probably won't do well here.
Thought maybe of the XT25SC90? I hear it can be crossed below 3khz if the impedance peak is taken care of... And they are still small format which I think would look best.
Then I do have a spare set of DX25BG60s. Might look a little goofy (to me at least) as they are almost the same width as the woofer flats. And I bet they would still be snoring while the 4"ers were at full blast.
hmm...
(Factory graph)
Comments
The SB19ST-C000-4 is 3 1/2" and modestly priced. It's currently out of stock at Madisound.
https://madisoundspeakerstore.com/soft-dome-tweeters-sb-acoustics/sb-acoustics-sb19st-c000-4-3/4-dome-tweeter-4-ohm/
The Dayton Audio ND25FA-4 might work. I've not used it but I have used the TD20F-4 with a BMR 4" woofer and it didn't sound bad at all for the price.
https://parts-express.com/Dayton-Audio-ND25FA-4-1-Soft-Dome-Neodymium-Tweeter-275-059?quantity=1
Ron
I've been curious about the Dayton Audio ND28F-6 but I haven't heard it nor seen any comments/reviews. If you wait until July 4th I bet PE will have a 10% or 12% off sale.
Also consider some of the 21mm SB Acoustics tweeters on sale at Meniscus. They might be more than you need, but I bet they'd sound good.
I used the Dayton ND25FA with ND105 4 inch woofers, and I really like the sound. The XT25 would work very well over about 3Khz.
MTMs are a whole lot of fun - built several.
Added the factory graph for reference.
I was shying away from tweets with no rear chamber as that seems to bump the Fs north of 1khz. But maybe you guys know something I don't.
I had even eyeballed the NE25VTS, but they cost the same as XT25BG60 (Beast nipples) at PE right now (~$37). And by that point I bet the performance outweighs the larger size anyway. So I was not realy looking to spend more than that if not using something I already had. Hard for me to justify pairing with sub-$20 woofers. But I suppose It is not impossible to convince me otherwise.
IDK why I'm gravitating so much toward Peerless. Just seemed neat to keep it an all peerless build since we may soon lose access to them. But I should look at other stuff too.
A little while ago I think there was a dimple dome with same frame as the SB21SDCN that was on sale for something like $25. I was extremely tempted and may end up kicking myself for not jumping on it.
SB21SDCN is on sale at Meniscus for 25% off. 2 in stock. But you have to hit $100 to get the promo code.
I'd give the DX20BF's a try. I have them in my desktop speakers at work and think they sound really nice. Unless you are building in/on-walls that won't require any BSC then I think the little DX20 should keep up with a pair of those woofers. Since you already have them you could build a test baffle and take some real measurements to play with in Sim Land.
Go for the Peerless DX20. It looks good on an MTM.
I'm a big fan of the DX20, but 2K in a MTM seems like to much woofer
I try to do my research. General consensus I got was the DX20 would probably run into trouble much below 3khz. I saw a couple instances of it being crossed around 2.5k, Over at ampslab he crossed it with active 24db/octave on few woofers. https://ampslab-spk.com/hifi-drivers-2/ And Hifiside did it with a single 830855. https://midwestaudioclub.com/diy/discussion/1219/my-shop-kit I suspect that one is flying pretty close to the sun, but maybe saved by the 830855 low sensitivity after baffle step is worked in (probably ~80db/1w/1m)?
How does one test this anyway? Just keep upping the volume and measure the resonse until you start seeing power compression or distortion ramping up? Then see if that does or doesn't happen before you are above typical listening volumes?
I've used the DX20 at 2.5khz with no problems. My Peerless MLTL years ago.
The XT25SC90/50/40 can xover about 2.7kHz, just strap a 25-30 ohm across it.
I'm not sure the DX20 will meet it.
The ND25 I found sounds better 4k+, but is capable.
The ND28 could do it, and xover at 2k.
HiVi TN25 can xover at 3k easy, but not really much lower.
The Seas 22TFF or 22TAFG might work, and are 98mm frame.
Seas 27TFFNC/CG would work.
SB19 are out of stock at Mad.
Dayton trunk silkie or RS may look good butting flats, and would work.
H1264 buyouts could work.
Visaton SC10N would work.
InDIYana Event Website
Wolfy's Photobucket
You already HAVE the DX20's. Make a quick and dirty test baffle out of some scrap board and see if the DX20 plays well with a pair of those 4" woofers. You might be surprised
That or try those $5 buyout tweeters
Yeah, you can test at various power levels, and you will probably see distortion rising big at some power level.
Or you can just play music at various volumes - and you might hear the tweeter "struggling" or "complaining" - so that is a sign that you need to raise the Fc or go 3rd order or use Fs compensation.
If you didn't have the DX20s already, I'd suggest the Vifa BC25TG, it seemed to combine well with the SDS 830656 and 830657 drivers in my test builds. It would need a bit of padding of course, even in a MTM.
Geoff
If I were to try to pursue the DX20 I'd probably start with doing some volume level/distortion testing and make a decision from there.
But I've also got a pair of DA115s that the DX20s might be a more appropriate match for. Hmm, I do have a pair of SDS-160F25PR01s too. That could be an interesting 3-way tower (if I decide to slog through a 3-way again). Might be perfect for a friend I was just talking to earlier today about potentially doing a build for. Anyhoo, veering off topic.
Interesting about the ND28F. I imagine a notch would be required crossing that close to Fs. The sensitivity looks like it could match up pretty closely on it's own. Though, depending how much baffle step is baked in, there could be some room for a parallel resistor. Or, if I wanted to play around with shelving the droopy top end a little.
On a side note: I just finished tacking together some prototype crossovers for my Peerless 835004 woofers and those $5 buyout tweeters. They actually sound really good. Surprisingly the weak link is not the cheap buyout tweeter... it's midrange distortion from the super cheap buyout 6.5" Peerless SDS midbass. These cheap tweeters sound better than any Dayton tweeter I've heard.
That said I might buy 4 of those 830855 drivers and build a MTM with them and the buyout tweeters.
I've been waiting to hear how they actually sound vs measure. I'll probably pick some up next time I order something. Where did you end up crossing them over?
LR4 @2800 Hz. Super simple 3rd order electrical filter with only a padding resistor out front.
835004? Is that a buyout from like 2011?
Correct
The late Rob Elder used the 835004 in a 8 ohm MTM with the Vifa BC25TG tweeter, I looked at it to try and adapt a XO for a 830657 two way.
https://www.rob-elder.com/LouC/speakers/GarageMTM/Lecbos.html
Geoff
Uh no. That is a Lou Corragio project that Rob Elder is hosting for posterity.
InDIYana Event Website
Wolfy's Photobucket
You're quite right, of course Wolf - I've looked at that website enough to know - Lou has, sadly, passed away but I hope Rob is still very much with us.
Geoff
I did a project with a SDS-160F25PR01 in a 2-way a few years ago and looked back at my measurements for distortion (now that I know what I'm looking at). Distortion definitely creeps up quite a bit before crossed over. Wonder how bad it gets on the 830855.
Probably have to put this on hold for a bit. Have other projects I will need to get to first.
I posted HD of the 830855 in the Bottleships thread if I remember correctly.
InDIYana Event Website
Wolfy's Photobucket
Ok after seeing those distortion graphs it looks like the DX25BG60s would probably give me the best chance at the best sound for the $ (since I've already got em) by crossing em low to drop out rising distortion. Goofy looks be damned. The name "Fire Ants" came to mind.
Buttin the flats on that $5 tweet looks pretty cool though!
The way the curves stop at the flat sides creates points that naturally draws your eye to the center. Sort of the way horns do.
Something like this. Guess it doesn't look bad when the drivers are tighter together. Just something about the stretched look of alot of MTMs often seems a little odd to my eye. Probably when a full size tweeter is used with alot of gap still between.
I'm gonna keep the $5 buyout tweeter and $10 buyout woofer project as is. It actually sounds quite nice. Nice enough to actually put some finish on the MDF baffles and particle board boxes. I have a friend in mind who could really use them.