From the uploaded HR .txt file, so now you know 😉:
S1 = 992.12 cm^2 = width x depth
S2 = 992.12
Con = 19.56 cm = inside (i.d.) top plate to driver center
S2 = 992.12
S3 = 992.12
Con = 27.97 cm = driver center to port center
S3 = 992.12
S4 = 992.12
Con = 8.52 cm = port center to inside (i.d.) of bottom plate|
Ap = 50.00 cm^2 = port area
Lpt = 15.00 cm = vent length including the baffle thickness
Depends, i.e. a typical cab alignment is presumed to have a ~uniform particle density, but as its aspect ratio increases it's harmonic structure increasingly impacts individual responses if not within a 1/4 WL, so one way around wide spacing is to roll off one to create a 1.5 alignment.
This design is very atractive, very good value, I'm between the 3-65 and the LBVS, two very different design, Same woofer, similar tweeter
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Have you found any builds or reviews of your options : it would be great if you could get some listening impressions of the options before you decide on what to build
Geoff
Geoff
Both have some reviews and they say they sound great for the cost and size, Right now I'm leaning more towards the 3-65, the 3 drivers are available and very cheap but the XO needs to many parts, I don't know how much they cost.
3 way crossovers are almost always more expensive than two ways and almost always have more parts. I haven't costed the crossover parts for the 3-65 but would guess it costs around double that for the LBVS. the 3-65 crossover has 21 parts, the LBVS as designed, nine parts.
In Oz, the woofer inductors alone will cost almost as much as the woofers!
There are some large-ish (i.e. expensive) inductors in the circuit and the tweeter circuit is complicated. You will have to be very careful to lay out all the parts and connect and solder everything correctly, but be methodical and don't be afraid to ask for help.
It's up to you, really: if this is going to be your only pair of DIY speakers and you intend to keep them for a long time, you will (probably) not regret the time, money and patience that you put into the 3-65s. The cabinet for the 3-65s looks a bit harder to build, but only a bit.
If it's for a bit of fun now, I'd go for the LBVS with the knowledge that you'll need to play with the crossover a bit.
Geoff
In Oz, the woofer inductors alone will cost almost as much as the woofers!
There are some large-ish (i.e. expensive) inductors in the circuit and the tweeter circuit is complicated. You will have to be very careful to lay out all the parts and connect and solder everything correctly, but be methodical and don't be afraid to ask for help.
It's up to you, really: if this is going to be your only pair of DIY speakers and you intend to keep them for a long time, you will (probably) not regret the time, money and patience that you put into the 3-65s. The cabinet for the 3-65s looks a bit harder to build, but only a bit.
If it's for a bit of fun now, I'd go for the LBVS with the knowledge that you'll need to play with the crossover a bit.
Geoff
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Hello Geoff!
Wow, too many parts, now days capacitors and inductors cost more than ever, the only thing I dont like about the 3-65 are the tweeters, why they use the cheapest XT when the XT25TG30-04 is only $10 more and very similar specs but lower freq. resonance, maybe the name 3-75 does not sounds as great as 3-65, jejeje
The curve response of the GBS-85N25PR03-04 looks very flat from 250 Hz to 2000 Hz, so the XT25TG30/60 makes more sense, Do you think if I buy the XT25TG30-04 87.2 dB instead of the XT25SC90-04 86.8 dB?
the 3-65 will be for latter but I will buy the drivers before they get out of stock.
Wow, too many parts, now days capacitors and inductors cost more than ever, the only thing I dont like about the 3-65 are the tweeters, why they use the cheapest XT when the XT25TG30-04 is only $10 more and very similar specs but lower freq. resonance, maybe the name 3-75 does not sounds as great as 3-65, jejeje
The curve response of the GBS-85N25PR03-04 looks very flat from 250 Hz to 2000 Hz, so the XT25TG30/60 makes more sense, Do you think if I buy the XT25TG30-04 87.2 dB instead of the XT25SC90-04 86.8 dB?
*If it's for a bit of fun now, I'd go for the LBVS with the knowledge that you'll need to play with the crossover a bit.
Yes, I will start with the LBVS, easier and I already have the drivers and some XO parts.the 3-65 will be for latter but I will buy the drivers before they get out of stock.
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1.6dB probably won't make that much difference, but that's only the 'offcial' specs anyway; could be different in real life. DB output is only a part of the story in any case: impedance, sound, frequency response and other factors are important too. The SC tweeter might look cheap but it's not really as it needs more parts in this project.
However, the SC can sound very good, I've used it in an MTM with Peerless 830656 and it's very nice; the tweeter circuit in that project doesn't have as many parts as the 3-65.
If you're going to build the 3-65 eventually, I would advise building it as designed. You won't be able to substitute the tweeter without re-designing the crossover as the XT25TG will most likely require different parts.
Geoff
However, the SC can sound very good, I've used it in an MTM with Peerless 830656 and it's very nice; the tweeter circuit in that project doesn't have as many parts as the 3-65.
If you're going to build the 3-65 eventually, I would advise building it as designed. You won't be able to substitute the tweeter without re-designing the crossover as the XT25TG will most likely require different parts.
Geoff
If it needs more parts is because it need more corrections and its not good?
I did not understand
I agree with you, I will follow your advice and buy exactly the same models, I dont have the knowledge to modify the XO.
The XT25TG will go for the LBVS and the 3-65 as it is, $128 for the 6 drivers seems to be very good deal, I hope the XO don't cost more than the drivers.
Who designed your MTM with 830656+SC?
Gustavo.
My MTM was designed by a longstanding member of the Parts Express Tech Talk and MidWest Audio Club, who's designed several award-winning speakers. His MTM placed a very close second in the "Best Iron Driver" contest in 2012 and I asked him if he would kindly share his design with me.
The winning entry in that competition was also an MTM with the 830656 (the woofer they had to use) and it had the Vifa XT25TG which you're going to use. All the details are in Parts Express Tech Talk Forum, just search for 'Best Iron Driver 2012'.
My knowledge of crossover design is very basic, but using more parts may not be the sign of a poor driver, it's often so the designer can get the sound and characteristics they want.
For example, the SC tweeter circuit in my MTM uses seven parts and looks nothing like the crossover in the 3-65s, which uses 11. In another Parts Express DIY project, five.
Likewise, the Dayton DC28F tweeter crossover as used in the "Tritrix" speakers uses three parts; in another project on this Forum, it has eight parts.
If you lived in Oz, the crossover for the 3-65 would probably cost more than the drivers, depending on the spec of the parts used.
Geoff
The winning entry in that competition was also an MTM with the 830656 (the woofer they had to use) and it had the Vifa XT25TG which you're going to use. All the details are in Parts Express Tech Talk Forum, just search for 'Best Iron Driver 2012'.
My knowledge of crossover design is very basic, but using more parts may not be the sign of a poor driver, it's often so the designer can get the sound and characteristics they want.
For example, the SC tweeter circuit in my MTM uses seven parts and looks nothing like the crossover in the 3-65s, which uses 11. In another Parts Express DIY project, five.
Likewise, the Dayton DC28F tweeter crossover as used in the "Tritrix" speakers uses three parts; in another project on this Forum, it has eight parts.
If you lived in Oz, the crossover for the 3-65 would probably cost more than the drivers, depending on the spec of the parts used.
Geoff
Looks for future proyect, so many speakers, saddly so little time to build them, I need to choose wisely
the MTM you're writing about is this one?
Yes, the 3-65 XO looks expensive, the cabinet looks not to easy to build either but if they will sound great worth the try.
but...
before I start cutting MDF, A friend wants to buy my XT25BG60-04 and with that money buy others drivers and choose other design, any advice on this?
I like simplicity but complete range of frequency, good low bass, mid and highs, not too much level, right now I have my Bagby's (RIP) Caritas speakers that I like a lot, with new music bass is more than enough but with rock oldies I wish there where more bass, thats why I'am looking for a bigger box, I post you my current boxes, by the way, AVF is my brand of Acoustic panels that I build for living.
Thanks for your help Geoff.
Gustavo
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Yes, they're the speakers I mentioned; I must say that the MTM speakers I made with the XT25SC90s sound really, really good.
If your friend is looking to use your tweeters, I'd suggest doing a Google search on something like 'Vifa XT25BG60 DIY speakers' and see what comes up.
It's been used in many projects. Of course, it was used in the speaker which inspired your initial idea: https://projectgallery.parts-express.com/speaker-projects/birthday-build/
Here's a project which uses the BG60, has some good background material:
https://speakermakersjourney.blogspot.com/2016/05/lm-1-bookshelf-crossover.html
The iron driver MTMs obviously sound very good, but the size and nature of the 830656 means that they don't have really low bass extension.
Here's a review of your tweeter:
And a review of the XT25SC90:
As for other projects, there are many which could suit your needs, depending on your budget, room size, whether you can get the drivers etc.
Geoff
If your friend is looking to use your tweeters, I'd suggest doing a Google search on something like 'Vifa XT25BG60 DIY speakers' and see what comes up.
It's been used in many projects. Of course, it was used in the speaker which inspired your initial idea: https://projectgallery.parts-express.com/speaker-projects/birthday-build/
Here's a project which uses the BG60, has some good background material:
https://speakermakersjourney.blogspot.com/2016/05/lm-1-bookshelf-crossover.html
The iron driver MTMs obviously sound very good, but the size and nature of the 830656 means that they don't have really low bass extension.
Here's a review of your tweeter:
And a review of the XT25SC90:
As for other projects, there are many which could suit your needs, depending on your budget, room size, whether you can get the drivers etc.
Geoff
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I read and watch all the links, the XT25BG60 that I'm about to quit seems to be very respected, I guess i just need to find other people's proyect with a woofer that is avaliable, the Peerless 830991 is out of stock and he says "The $45 fiberglass driver could be inexactly substituted by the the Peerless 830656 paper cone woofer" so inexactly it's not the best I guess hehehe.
I'm about to order the drivers needed for the 3-65 and maybe order another pair of XT25BG60 for the LBVS or other design.
Thanks for the links and info
Gustavo
Have tried to send a PM but the Forum limits me to five replies in an hour, have some advice for you on the MTM, will send later
Geoff
Geoff