Good for you, Tony. It's a great hobby. 🙂
Ferrite Core coils don't cost the earth. we get 'em for a fiver for 4mH here:
4 00mH Ferrite Inductor
I dug up a US tweeter I would take on at Madisound, Goldwood GT-25 :
The Madisound Speaker Store
Believe me, cone tweeters sound extremely musical. Good technical reasons why, too. The best thing? Cheap as chips!
Otherwise we are just building a so-so speaker. I don't do that stuff.
Ferrite Core coils don't cost the earth. we get 'em for a fiver for 4mH here:
4 00mH Ferrite Inductor
I dug up a US tweeter I would take on at Madisound, Goldwood GT-25 :
The Madisound Speaker Store
Believe me, cone tweeters sound extremely musical. Good technical reasons why, too. The best thing? Cheap as chips!
Otherwise we are just building a so-so speaker. I don't do that stuff.
Not so cheap for the coils on our side of the pond!
Jantzen 4.7mH 15 AWG P-Core Inductor | 255-116
How many famous speakers were made with that two inch paper cone $2 Peerless tweeter? My old Tandburgs have them. Too many to count I bet. Still, modern materials and design produce far better tweeters now. They seem to converge on about a one inch dome usable above 2500Hz. Marketing, or is that what the physics works out to be?
Jantzen 4.7mH 15 AWG P-Core Inductor | 255-116
How many famous speakers were made with that two inch paper cone $2 Peerless tweeter? My old Tandburgs have them. Too many to count I bet. Still, modern materials and design produce far better tweeters now. They seem to converge on about a one inch dome usable above 2500Hz. Marketing, or is that what the physics works out to be?
You are right Tony, sometimes these threads go sideways. After you build a few, you too will have ideas on what is more important than other things. I have gotten on the baffle radius campaign after my experiences building a Seas based system. I believe far too many tweeter problems are nothing but the sharp edges on the cabinet.
The other thing to remember is these threads are public, so we may jump in to make more correct a statement that may have been fine for the question asked, but is not totally correct and we don't want the miss-information to spread out of context. A BBC reporter last week claimed gold was the best conductor. Sigh.
It sounds like we are getting you hooked, so may I recommend getting Testing Loudspeakers, by Joe D'Apolitto. It teaches you what you are really measuring the old way. ( generator and VTVM). So when you splurge on a WooferTester you know what it is doing. Not free like the other sources, but I believe it is invaluable. Basic knowledge always pays off.
The other thing to remember is these threads are public, so we may jump in to make more correct a statement that may have been fine for the question asked, but is not totally correct and we don't want the miss-information to spread out of context. A BBC reporter last week claimed gold was the best conductor. Sigh.
It sounds like we are getting you hooked, so may I recommend getting Testing Loudspeakers, by Joe D'Apolitto. It teaches you what you are really measuring the old way. ( generator and VTVM). So when you splurge on a WooferTester you know what it is doing. Not free like the other sources, but I believe it is invaluable. Basic knowledge always pays off.
Looks like you're stuck with boutique parts there...😀
Robin Marshall: A Modicum of Genius Page 4 | Stereophile.com
Hi,
Given the alternatives its a poor cheap driver and cannot be used
with cheap tweeters. I'm not interested in discussing a x/o you
say will work but won't discuss. I couldn't care less. Far better
drivers are available for not much more, a better choice.
rgds, sreten.
* Your business seems to be spouting BS about all and sundry
loudspeakers designs based on using the wrong drivers for
the design in a simulation package you cannot import drivers.
Give the misinformation a rest, you don't know that x/o
will work because you haven't modelled it with real drivers.
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No disrespect meant towards system7 or anyone else here. This is all crazy insanity and making my head spin. I'm loving it though and having a ball.
I have learned from this forum that my junk MCM drivers have some really bad characteristics but yet at least one successful design was done with these. But wait!!!!. Hold on. The inexpensive HiVi B4N's have some nasty characteristics as well and yet again there are several successful designs with those.
But it get worse. I mentioned I have one of these tweeters.
http://www.parts-express.com/pedocs/specs/264-1028-vifa-bc25sc06-04-specifications-46535.pdf.
I'm told its no good and this one is better at 1/4th the price:
http://www.parts-express.com/pedocs/manuals/270-018-goldwood-gt-25-manual.pdf
Now as a newbie to this, looking at those curves one looks pretty funky and strange to me.
Which one is better. I "gots" to know. How is a newbie supposed to make any sense of this.
Tony
To drive Tony crazy... Steve, when was you copy quote taken? I can well agree ( who are any of us to argue with either of the persons mentioned) but the time context is important. If you were to take a typical silk dome from the 70's, yes, the breakup was too low and bad things could happen. Dome sizzle was common. Take a modern dome, HDS or TBFC/G for example. Their breakup is well clear of the audible range. That does leave them susceptible to inter-modulation issues depending on the behavior of the amplifier. I can assure you, cones have breakup issues too. Just different ones.
I would love to see a modern well done 2 inch cone tweeter. It would have the possibility of crossing over low enough to make many mid-woofers easier to deal with and not put the crossover smack in the middle of our most sensitive hearing range.
I would love to see a modern well done 2 inch cone tweeter. It would have the possibility of crossing over low enough to make many mid-woofers easier to deal with and not put the crossover smack in the middle of our most sensitive hearing range.
Steve,
To add insult to injury, a spool of enameled wire costs more per foot than pre-made coils. Spool made by Belden here, coils made by children in China out of who knows what.
sreten,
cheap drivers are just fine for learning how to measure, practice the woodworking skills to get one's shop and jigs set up. Fine for playing with tools. Build with cheap parts and you have a garage speaker. Then one has a better understanding of what to look for in a better quality driver. As we all too well know, some of them are not easy to deal with either!
Tony: What to look for in a driver:
* Suitable as far as if it can push enough air for the frequencies you need it to. No, that 5 inch "sub" will not produce 100 dB in a 400 sq foot room at 20 Hz. It may try, once.
* As low harmonic distortion as you can afford. Unfortunately you have to measure for yourself or trust others who have. It is still complicated. As an example, the Vifa XT-25 is an almost cheap tweeter. Above 3500 Hz, it is one of the best at any price. Cross it over too low and it is a horrid thing. Nothing in the published specs will tell you this.
* Easy to use. That is tough. Experience helps. The published frequency charts don't tell the full story, but the uglier they are, the likelihood it is hard to use goes up. When you see a lot of wiggle right before it rolls of on the top end, that is breakup. You have to suppress or avoid that. Sometimes easy, sometimes very hard. The further the breakup is from the crossover the better. Dayton RS drivers give me fits needing both a low crossover and a notch filter at least, but the results are great. The Seas reed paper driver gets by with one notch. The SilverFlute required massive driver modification to be at all tolerable. A crossover-alone solution required over 30 parts (On paper. I did not build it) The new Seas woven poly cones look very easy to deal with. A long slope, even if smooth in the usable range can be hard to deal with. No easy answers. Sorry.
The market seems to support the 5 to 7 inch mid-woofer and one inch tweeter augmented by a sub. For better or worse, that seems to be where the action is. Step outside that and it gets harder.
To add insult to injury, a spool of enameled wire costs more per foot than pre-made coils. Spool made by Belden here, coils made by children in China out of who knows what.
sreten,
cheap drivers are just fine for learning how to measure, practice the woodworking skills to get one's shop and jigs set up. Fine for playing with tools. Build with cheap parts and you have a garage speaker. Then one has a better understanding of what to look for in a better quality driver. As we all too well know, some of them are not easy to deal with either!
Tony: What to look for in a driver:
* Suitable as far as if it can push enough air for the frequencies you need it to. No, that 5 inch "sub" will not produce 100 dB in a 400 sq foot room at 20 Hz. It may try, once.
* As low harmonic distortion as you can afford. Unfortunately you have to measure for yourself or trust others who have. It is still complicated. As an example, the Vifa XT-25 is an almost cheap tweeter. Above 3500 Hz, it is one of the best at any price. Cross it over too low and it is a horrid thing. Nothing in the published specs will tell you this.
* Easy to use. That is tough. Experience helps. The published frequency charts don't tell the full story, but the uglier they are, the likelihood it is hard to use goes up. When you see a lot of wiggle right before it rolls of on the top end, that is breakup. You have to suppress or avoid that. Sometimes easy, sometimes very hard. The further the breakup is from the crossover the better. Dayton RS drivers give me fits needing both a low crossover and a notch filter at least, but the results are great. The Seas reed paper driver gets by with one notch. The SilverFlute required massive driver modification to be at all tolerable. A crossover-alone solution required over 30 parts (On paper. I did not build it) The new Seas woven poly cones look very easy to deal with. A long slope, even if smooth in the usable range can be hard to deal with. No easy answers. Sorry.
The market seems to support the 5 to 7 inch mid-woofer and one inch tweeter augmented by a sub. For better or worse, that seems to be where the action is. Step outside that and it gets harder.
BTW, for a first build, I would use the Vifa, not the Goldwood. My preference. Plots and specs do not tell the full story so the cone may have attributes hidden from me and the distortion in the Vifa is, well it is a really cheap tweeter. (better than you find in most $500 store speakers though)
Lets get this thread back into context
OP is having a "Learning experience" that is often better dome with drivers on the lower end of the quality spectrum as it really makes you appreciate the easy designing qualities of good well controlled drivers like the classic Vifa and Peerless [ and others of course] but my limited experience says that the XO often costs more than the drivers except for those rare instances when a cap on the tweeter is all you need.
OP is having a "Learning experience" that is often better dome with drivers on the lower end of the quality spectrum as it really makes you appreciate the easy designing qualities of good well controlled drivers like the classic Vifa and Peerless [ and others of course] but my limited experience says that the XO often costs more than the drivers except for those rare instances when a cap on the tweeter is all you need.
I seem to have someone following me around like a bad smell here. But I'll stick to Tony's speaker. 😀
As mentioned, my weapon of choice would be the Visaton TW70 here. I have a couple of these along with some goodish Morel soft domes and like what I hear. If there is a modern tweeter I like the look of, it's not any metal dome, it is the fabric Vifa XT25 ring radiator.
But that Goldwood GT25 really looks OK to me. I know what to do with it, but am no longer feeling so generous with ideas to all and sundry, and will PM you a circuit if wanted, Tony. We might look at an XT25 circuit some other day. For now, that is mission creep into the more exotic. Right now, we are doing cheap and cheerful. Well, reasonably cheerful, most of us...🙄
As mentioned, my weapon of choice would be the Visaton TW70 here. I have a couple of these along with some goodish Morel soft domes and like what I hear. If there is a modern tweeter I like the look of, it's not any metal dome, it is the fabric Vifa XT25 ring radiator.
But that Goldwood GT25 really looks OK to me. I know what to do with it, but am no longer feeling so generous with ideas to all and sundry, and will PM you a circuit if wanted, Tony. We might look at an XT25 circuit some other day. For now, that is mission creep into the more exotic. Right now, we are doing cheap and cheerful. Well, reasonably cheerful, most of us...🙄
Attachments
Zaph says:
Vifa BC25SC06-04 ($12) - This is a low cost fabric dome tweeter with mild horn loading. Very nice harmonic distortion but a mild internal reflection causes a hiccup in the response curve at 4kHz. Response is otherwise smooth. Good value. Tested May 2008.
The tweeter is used in the Stentorians:
Speaker Design Works
The tweeter is used in the Stentorians:
Speaker Design Works
I'm absolutely convinced now that when I made my first post here you guys all got together and said "we got a live one here - lets have some fun with him and drive him over the edge" 🙂
What on earth is a HDS or TBFC/G? Also, these days where on earth do you buy a store bought $500 speaker?. Back 40 years ago there were stereo stores on every street corner mostly selling junk , the big department stores selling the same with some decent stuff mixed in and the likes of Radio Shack and Lafayette etc, offering the same thing. These days, unless I'm blind I have not seen anything offered in common stores beyond those 6 or 8 or 10 speaker home theater systems.
Thanks for post #68. I learned a little more.
Tony
Well, good news, Tony. I've had a look at the PE "Phenolic Ring Tweeter".
Phenolic Ring Tweeter 8 Ohm | 270-252
This is based on the old Acoustic Research cone tweeter. Bit of a classic. 😀
Quite a big jobbie, 108mm dia aka 4.25 inches. It happens to be easy to work with. The coil and cap values in the treble filter do have to be accurate though, for reasons I will tell you about privately later, because I'm not showing the "Piece of Resistance" of the circuit here. I also looked into reflex alignment. 40-60L with a port is straightforward enough as an add on, if the muse takes you. This is working out very nicely indeed, IMO. 😎
Phenolic Ring Tweeter 8 Ohm | 270-252
This is based on the old Acoustic Research cone tweeter. Bit of a classic. 😀
Quite a big jobbie, 108mm dia aka 4.25 inches. It happens to be easy to work with. The coil and cap values in the treble filter do have to be accurate though, for reasons I will tell you about privately later, because I'm not showing the "Piece of Resistance" of the circuit here. I also looked into reflex alignment. 40-60L with a port is straightforward enough as an add on, if the muse takes you. This is working out very nicely indeed, IMO. 😎
Attachments
FWIW, back at the beginning of the thread I was going to suggest the OP going ahead and building his stillborn Bang! Project with a slightly modified cab design and similar tweeter since it truly is a decent ‘bang/buck’ design IMNSHO, but it went so 'sideways' before I had a chance to type it up, so moved on.
Since you've ~ 'opened the door' though............the Goldwood GT525 tweeter, while not looking physically the same, has the same basic specs as the original and at least has the same notch on axis in its response that Dan noted his XO dealt with, so figured that the Bang!'s XO would probably be 'close enough' for the OP's intended app [for near term anyway] until he’d accumulated enough knowledge to design/build an upgraded system or at least ask more precise Qs and not be bamboozled by all the ‘diversity’ of an ‘open’ source forum where there’s a wide range of [in]experience available, not to mention those with specific agendas, to amuse/confuse/abuse the uninitiated………...
Worst case, he gets to learn a bit about XOs and [super] tweeter selection by tweaking it to personal ‘taste’.
WRT his desire for a sealed Vs the Bang!’s vented alignment and 30” Vs 28” o.d. height, building this cab a couple of inches longer and either retuning and/or critically damping the vent to get what some consider the best of both types of alignments or just filling the bottom up with scrap wood or similar for more stability if he can’t find an audibly pleasing tuning seems the best overall solution.
Plans: http://stereointegrity.com/Files/BangPlans.pdf
GT525: Goldwood GT-525 1" Soft Dome Tweeter | 270-182
Thoughts, S7, Tony?
GM
S7, GM and anyone else who is still interested.
I'll start by saying I bought sheet of 3/4" plywood today. Had to settle for Poplar. They only had one sheet of birch and it was pretty banged up and I did not feel like dealing with MDF.
With that said I'm ready to go but have no idea where I'm going. As far as a tweeter, I'll buy any tweeters that 2 people here agree on. I don't care if their $3, or $20 or whatever and I'll use whatever crossover S7 comes up with. However if one person is saying use this and the others saying use that then I'm just going to buy one more of the Vifa BC25SC06-04 since I already have one.
As far as sealed or vented it makes no real difference to me. I would assume I'd be happier with the lower bass of the vented, you guys tell me. I will heed your advice.
As far as following the Adire Bang plans I have one concern. I dont know if this means anything but if you check out the link below it seems the MCM 55-1170 specs may have changed since the days of the Bang. There is a post there from Dan Wiggins. I have no clue what they are talking about. You guys would know.
Audio Asylum Thread Printer
For reference here are the current specs of the 1170
Specifications::
Power Capacity: 45W/60W RMS/peak
Sensitivity: 90dB (W/M)
Impedance: 8ohm
Re: 6.8ohm
Le: 0.48mH
Frequency response: 40Hz~3.5KHz
Fs: 40Hz
Qts: 0.50
Qes: 0.67
Qms: 2.00
Vas: 30.48 (liters)
Xmax: 2.55mm
And finally, again I don't know if this matters but my testing of the four 55-1170 I have on hand show, an Fs of 55Hz
I'm all ears and ready to build and order tweeters.
Thanks
Tony
I'll start by saying I bought sheet of 3/4" plywood today. Had to settle for Poplar. They only had one sheet of birch and it was pretty banged up and I did not feel like dealing with MDF.
With that said I'm ready to go but have no idea where I'm going. As far as a tweeter, I'll buy any tweeters that 2 people here agree on. I don't care if their $3, or $20 or whatever and I'll use whatever crossover S7 comes up with. However if one person is saying use this and the others saying use that then I'm just going to buy one more of the Vifa BC25SC06-04 since I already have one.
As far as sealed or vented it makes no real difference to me. I would assume I'd be happier with the lower bass of the vented, you guys tell me. I will heed your advice.
As far as following the Adire Bang plans I have one concern. I dont know if this means anything but if you check out the link below it seems the MCM 55-1170 specs may have changed since the days of the Bang. There is a post there from Dan Wiggins. I have no clue what they are talking about. You guys would know.
Audio Asylum Thread Printer
For reference here are the current specs of the 1170
Specifications::
Power Capacity: 45W/60W RMS/peak
Sensitivity: 90dB (W/M)
Impedance: 8ohm
Re: 6.8ohm
Le: 0.48mH
Frequency response: 40Hz~3.5KHz
Fs: 40Hz
Qts: 0.50
Qes: 0.67
Qms: 2.00
Vas: 30.48 (liters)
Xmax: 2.55mm
And finally, again I don't know if this matters but my testing of the four 55-1170 I have on hand show, an Fs of 55Hz
I'm all ears and ready to build and order tweeters.
Thanks
Tony
Man, I wish you lived closer. We'd be done by now. Close your eyes, pick a tweeter and move on. They are going to be good enough whatever you choose. This thread is becoming a circus with all the suggestions about this and that when all you want is a little background noise. No offence to all who are helping but you could be building your second set by now.
If you still can't decide on a tweeter, send me your address. I'll mail you something, no charge. I've got things on shelves that are only getting dustier as we type.
If you still can't decide on a tweeter, send me your address. I'll mail you something, no charge. I've got things on shelves that are only getting dustier as we type.
I never hurry a speaker myself! That post from GM was really very helpful. Having had a look at the 46L reflex Adire Audio Bang!, well, what's not to like? 🙂
That Goldwood GT-525 looks like it'll do the job as a substitute. I suspect it's made by MCM anyway. Fs around 850Hz should keep it stable, and near 95dB efficiency, which is a requirement.
I think my idea would be too fiddly to get to work here. I'd change it now based on reading the Bang! pdf. It needs a smaller coil than I started with and the notch goes in favour of a single capacitor. But, that's a very tricky polycone woofer really, and Dan Wiggin's circuit is highly competent in taming its oddities.
I ran up the Bang! electrical filter response below. Nice. Quite complex to build, but, hey.
That Goldwood GT-525 looks like it'll do the job as a substitute. I suspect it's made by MCM anyway. Fs around 850Hz should keep it stable, and near 95dB efficiency, which is a requirement.
I think my idea would be too fiddly to get to work here. I'd change it now based on reading the Bang! pdf. It needs a smaller coil than I started with and the notch goes in favour of a single capacitor. But, that's a very tricky polycone woofer really, and Dan Wiggin's circuit is highly competent in taming its oddities.
I ran up the Bang! electrical filter response below. Nice. Quite complex to build, but, hey.
Attachments
I don't know if your intent was to insult me but I'll assume it was not and I'm not in any need of any handouts. Maybe there is something wrong with me but along the way here, I asked 4 or 5 basic questions which did in fact get responses. However most of the responses seemingly had nothing to do with the question I asked or were just full of overly complex technical jargon that a newbie would never understand OR they were ******* contest challenges, most aimed at S7 who has been trying to be help full. I am going to ask one more question in my next post in response to S7 about how big I should cut the plywood I bought today. If you want to close this after that I'll leave it up to you.
Thanks
Tony
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