djn posts are interesting, but they belong to 'ob gallery' thread 🙂
Pretty sure mods can do that (and delete my post).
Pretty sure mods can do that (and delete my post).
Awesome thanks for that info; I had to choose between 18mH and 22mH and went the latter as I knew I could always reduce it if needed. But if I don’t, so much the better!
John B always said to me that the inductor ought to be 22-24mH, but they aren’t available thru normal channels.
Thanks Pano and everyone for you input, very much appreciated. I feel vindicated in buying the mundorf 22mH inductors now, even at the additional expense!
Hope you all have a safe and fun restive season!
Cheers from Oz!
Hope you all have a safe and fun restive season!
Cheers from Oz!
With the 22mH coil you might need to adjust the cap and resistor on the tweeter.
No big deal, adjusing the resistor is something everyone should do in their own listening space.
No big deal, adjusing the resistor is something everyone should do in their own listening space.
OK, really incredible thread that I've been reading through for the past few months! Thank you John Busch (RIP) and Pano and all the others who have contributed here. I am going to try to build the Ultras and will be my first speaker build......
I think I have put together a current list of all the correct parts and prices. May I ask Pano/all to review and provide feedback and suggestions to noob speaker builder? Here is what I've got so far:
Parts List:
Looking forward to this and thank you all once again!
David
I think I have put together a current list of all the correct parts and prices. May I ask Pano/all to review and provide feedback and suggestions to noob speaker builder? Here is what I've got so far:
Parts List:
- Parts Express (x 2 for each speaker)
- 15” GRS Woofers 15PF-8 #292-415 $37 $74
- 3-1/2” Peerless Mid-tweeters TC9FD18-08 #264-1062 $23 $46
- C1: 6.2uF cap Dayton Audio 250V #027-236 $5.50 $11
- R1: 8ohm resistor Mills 12W #005-8 $9.50 $19
- R2: 15ohm resistor Mills 12W #005-15 $9.50 $19
- L2: Air-core coil 4.7mH 14 gauge ???
- L3: 0.4mH air core (woof trap) coil #257-308 $17.50 $35
- C2: 15uF cap (woof trap) Dayton 250V #027-248 $12 $24
- Xover board 5”x7” ?? #260-194 $7.50 $15
- Standoff screws for board (???)
- Speaker posts (BPA-38G) ??? #091-1245 $10 $20
- Wire 25’ 14 AWG Consolidated ??? #101-791 $21 $21
- Pan head screws - #8? #6?x3/4”
- What else???
- US Coils (uscoils.us)
- L1: 20mH Iron-core 16 gauge inductor #USSQ55-16-20000 $39 $78
- L2: Air-core coil 4.7mH 14 gauge #USAC36-16-4700 $35.50 $71
- L3: 0.4mH air core (woof trap) coil #USAC12-14-400 $17 $34
- Lumber yard
- 2 pcs. 24”x48” ¾” BB plywood (or ?? if BB not available ??)
- 1 pcs. 1”x6”x8’ pine (wings)
- 1 pcs. 1”x1”x8’ pine (brace)
- 1 pcs. 24”x24” ¾” plywood (base)
- Glue/screws/woodworking friend!
Looking forward to this and thank you all once again!
David
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Whoa! At a local lumber yard (not Home Depot or Lowes) the cost for two pieces of 24x48x.75 (real) Baltic Birch is $140. That puts this speaker project at ~$700. (Inflation calculator puts $350 in 2007 equal to $513 today)...
Yeah that's nuts! You can use other plywood or even OSB, but BB is the best thing for speakers. Keep looking, you should find something. A thin sheet of ply glued over OSB can work well. Also the price of inductors has also far outpaced inflation.
Your list looks good, of course you have most inductors listed twice, so that you have a choice.
For the woofer trap cap you can substitute Part #027-344 electrolytic. Listen to hear of the trap helps you first, then upgrade.
I like those crossover perf boards, but I usually build with Euro-style screw terminals to start, which makes it easy to fine tune and swap out parts.
You can buy the Dayton power resistors to start, and get a few similar values. You do need to tune the crossover to your room for best results. When you find the resistor values you like, then you can think about the Mills. John Busch loved the Mills resistors, I couldn't not hear the difference. 😉
If the big 20mH inductors are breaking the bank, you can use the inductor from Parts Express crossover Part #266-442. Not perfect, but it will get you up and running for $21 each.
There are trade-offs to be made. Alas on this project the price of parts has gone up faster then general inflation, making this not so cheap anymore.
For the woofer trap cap you can substitute Part #027-344 electrolytic. Listen to hear of the trap helps you first, then upgrade.
I like those crossover perf boards, but I usually build with Euro-style screw terminals to start, which makes it easy to fine tune and swap out parts.
You can buy the Dayton power resistors to start, and get a few similar values. You do need to tune the crossover to your room for best results. When you find the resistor values you like, then you can think about the Mills. John Busch loved the Mills resistors, I couldn't not hear the difference. 😉
If the big 20mH inductors are breaking the bank, you can use the inductor from Parts Express crossover Part #266-442. Not perfect, but it will get you up and running for $21 each.
There are trade-offs to be made. Alas on this project the price of parts has gone up faster then general inflation, making this not so cheap anymore.
Watching this thread for a while; but if I would consider building it, I would certainly use an active xover and a second stereo power amp. That would be far cheaper than a pair of those passive xovers.
Pardon the ramble ...
The $350 in 2007 did not included the lumber or paint. There may have been a cap and resistor missing, too, as they already existed in the parts pile.
I was new to speaker building and a local recommended MDF as he'd read it was the best thing for speakers. Learned a lot about speaker building in the following years and wouldn't use MDF again. But it was cheap so it would be fine for a quick build or to model a slightly different set of dimensions.
The Ultras were built with plywood. Partly for it's supposed sonic improvements but also to keep the weight of the speakers down. MDF is heavy and the Ultras are big.
But as stated earlier, by 2010 the price of building the Manzi was already a lot higher because of the cost of copper and the rise in the price of the woofer. It's why John came up with the Ultra (low cost) model. Unfortunately that's gone up, too. That's just the nature of things over the long run.
I built my current OB speakers based on really enjoying the Manzanitas for a year+. I kept my overall costs down via multiple lucky scores of parts and drivers from this forum. The baffles are vinyl-veneered chipboard cabinet doors from Ikea's cheap rejects section. They were $5, each. There are many MUCH-less-expensive ways to get baffles than retail high-quality plywood. Thin, good-quality ply over OSB sounds like the smart frugal way for new material.
That seems like an easy path, but it's not. I tried and tried active with this design and some other OBs. I never got the great tonal balance and soundstage that John Busch achieved with his simple passive crossovers. Certainly on "should" be able to achieve it with active, but I never have.
Somewhere back in this thread a posted a starting point for an active version.
Thanks Pano, barryso, tschrama, and von Ah for taking the time to respond/provide inputs. I like the idea of those Euro screw terminals - will get some of those to start. I was looking/searching back for the discussions around active crossover alternative, but Pano sums it up that to date no one has succeeded as well as with the passive design. There are some OSB-haters out there - not as many as MDF, so still researching other options. Hmm, anybody have an opinion here on Radiata pine plywood??
What size wood screws for mounting the speakers - #6 or #8's?
What size wood screws for mounting the speakers - #6 or #8's?
The first Manzanita from 2007 was put together with what looks like OSB. They'd look fine with a coat or two of paint.
What about Wago type of terminal connectors? Or is the clip based lock not as good electrically as the screw terminals? If I am reading the crossover schematic correctly, it takes six 3-way connections and one 2-way.
daggerNC,
I don't have an answer to your question but will throw out an observation about the connectors in general.
I've not played with the various terminal connectors but have used the euro connectors since seeing them on John's build way back when.
There was a time when the terminal connectors were removed from the Ultras and the wires were wrapped together and soldered. It made a nice sonic improvement by removing a layer or so of grunge that hadn't even been obvious. It was a nice surprise.
Eventually ended up with the connectors again as it allows easy resistor swaps. It's silly as the crossover doesn't get changed anymore. But to the point, when you get the crossover right its worth taking the connectors out of the circuit.
I don't have an answer to your question but will throw out an observation about the connectors in general.
I've not played with the various terminal connectors but have used the euro connectors since seeing them on John's build way back when.
There was a time when the terminal connectors were removed from the Ultras and the wires were wrapped together and soldered. It made a nice sonic improvement by removing a layer or so of grunge that hadn't even been obvious. It was a nice surprise.
Eventually ended up with the connectors again as it allows easy resistor swaps. It's silly as the crossover doesn't get changed anymore. But to the point, when you get the crossover right its worth taking the connectors out of the circuit.