hello,
a few words from france! I need feedback about the basszilla or other fostex based DIY projects like the jericho horn or others before embarking on this undertaking! all advice welcome about which driver, cables and gear best suited!
thanks in advance
a few words from france! I need feedback about the basszilla or other fostex based DIY projects like the jericho horn or others before embarking on this undertaking! all advice welcome about which driver, cables and gear best suited!
thanks in advance
Anything Dick Olsher does is good, and well worth
the effort. This of course is no guarantee of satisfaction....
the effort. This of course is no guarantee of satisfaction....
Does anyone know any substitutes for the Audax PR380M2 used in the Basszilla kit? It costs $340 each from Madisound. Any cheaper drivers that would suit this task almost as well? I wouldn't mind sacrificing some efficiency of the bass driver, as bi-amping is an option for this setup.
--
Brian
--
Brian
BrianGT said:
Variac is using an Emminence i believe for his BassZilla ...
The big Audax PRs are pretty outstanding bass drivers. We used to use one that had a 103 dB/1W rating that just kicked butt (they don't seem to make it any more). PHL was formed from engineers that designed the original Audax PRs (including the one i mention) so their drivers are worth checking out.
dave
planet10 said:
I did a search, and it looks like Variac is using Selenium drivers:
I was cheap and bought Selenium drivers, but there is no doubt that the Audax drivers are better. I sometimes wish I had waited until I could afford them. If I like the Basszilla, I will upgrade them later.
Are they any good?
PHL drivers look very good. Do you know any vendors that sell their bass drivers?
--
Brian
Few years ago I built Jericho horns sized to FE164. About 1 year after I had built them I gave them to a friend. I kept the drivers. What I really didn't like about them was coloration they were producing having small volume behind driver (a lot of strong reflections) and considerable midrange output through horn mouth. Also, I found that whizzer cone is the main cause of upper midrange coloration of FE164. After cutting off the whizzer and instaling "phase plug" the sound is (to my ears) much better (and measurreably more linear) but it starts to roll off at about 12kHz. Dammar coating (lightly) also helps. Now, installed in 25lit. "mini-onken" they sound really nice. 🙂
Brian:
I can't give you any specific recommendations for a driver. I would just point out that the Audax rates the PR380M2 as 100 dB @ 1W/1M and it is really 95 dB.
When you look for a replacement, you might want to keep that in mind. 🙂
I suspect you are familiar with Audax's chart for this driver, but I'll put up the graphic just for the sake of completeness.
Good luck!
I can't give you any specific recommendations for a driver. I would just point out that the Audax rates the PR380M2 as 100 dB @ 1W/1M and it is really 95 dB.
When you look for a replacement, you might want to keep that in mind. 🙂
I suspect you are familiar with Audax's chart for this driver, but I'll put up the graphic just for the sake of completeness.
Good luck!
Attachments
Yup, I wish I had the Audax 380's, but at that price I knew it would be a couple of years 'till I could get them. I just dropped $350 on my Fostex FE 208 E sigmas. If I get my Basszilla tuned so it sounds great, maybe I'll consider an upgrade...
The Pass Labs guys like that driver a lot too, so there is no doubt they are special. Zylatron used to list them for about $100 less each, so that might be worth a try.The Audax's have a superbly flat response curve that doesn't roll off in the bass as much as most pro drivers.
To paraphrase Cyclotron Guy I think, he says that the biggest step is going to any reputable pro 15"driver.
I suspect I will be thrilled with my Selenium WPU1505 drivers, not having heard any others in a Hi Fi context. They also appear to be 95dB.
I haven't put'em in boxes yet, but I will be finishing the boxes this week because I will need them for my 50th birthday party as PA speakers for the bands. Of course I will be using a set of pro horn drivers instead of the Fostex's - couldn' risk blowing out those babies. Will be celebrating on a big spread down by Big Sur on the California coast. Got 3 bands so far: Jazz, Bluegrass, and Rock & Roll. Will have about 70 people- you Aussies think one keg (15 gal) will do the job? If you are in the area, give me an e-mail and I'll fill you in!!
Anyway..... back to the speaks... I am also planning to bi amp, using my HAfler 220 to power the woofers, which are less efficient than the Audax's. I will first use the passive crossover that Dick specs, but I'll have a Y connector splitting the input to my Son o Zens and the Hafler. The output of the Hafler will be sent through a low pass filter, then to the woofs. The SOZ output will go full range to the Fostex's. Anyone see a huge problem with this scheme? Yeah I know I'll need to adjust the Hafler output with a passive attenuator on the input, or a l-pad on the output.
The Seleniums are absolutely beautiful, with a massive cast frame.
I feel in retrospect that another model, the Selenium 15PW3CE might be a better sounding speaker, but I couldn't get over the stamped steel basket. It only costs about $70 from PartsExpress.
It has a sweet freq curve, and I have heard that lower power handling models, generally sound better. As an example look at the Hammer driver: steel frame and lower power capacity. I think it would be worth a try and at that price what have you got t o lose?
I heartilly recommend the Dick Olsher plans, just for the general info. HOWEVER, they are designed for the old Fostex FE 208 model which has been discontinued. Maybe if you guys asked, he will get going on a crossover and notch filter for the new 208. Tell himyou are waitin for the new design before buying!!
I hear you have to have a notch filter on the 208 to tame the big response peaks. The new 208 has only one peak, but a whopper.
I'll try changing Mr. Olshers filter to fit my driver, we'll see.
The Pass Labs guys like that driver a lot too, so there is no doubt they are special. Zylatron used to list them for about $100 less each, so that might be worth a try.The Audax's have a superbly flat response curve that doesn't roll off in the bass as much as most pro drivers.
To paraphrase Cyclotron Guy I think, he says that the biggest step is going to any reputable pro 15"driver.
I suspect I will be thrilled with my Selenium WPU1505 drivers, not having heard any others in a Hi Fi context. They also appear to be 95dB.
I haven't put'em in boxes yet, but I will be finishing the boxes this week because I will need them for my 50th birthday party as PA speakers for the bands. Of course I will be using a set of pro horn drivers instead of the Fostex's - couldn' risk blowing out those babies. Will be celebrating on a big spread down by Big Sur on the California coast. Got 3 bands so far: Jazz, Bluegrass, and Rock & Roll. Will have about 70 people- you Aussies think one keg (15 gal) will do the job? If you are in the area, give me an e-mail and I'll fill you in!!
Anyway..... back to the speaks... I am also planning to bi amp, using my HAfler 220 to power the woofers, which are less efficient than the Audax's. I will first use the passive crossover that Dick specs, but I'll have a Y connector splitting the input to my Son o Zens and the Hafler. The output of the Hafler will be sent through a low pass filter, then to the woofs. The SOZ output will go full range to the Fostex's. Anyone see a huge problem with this scheme? Yeah I know I'll need to adjust the Hafler output with a passive attenuator on the input, or a l-pad on the output.
The Seleniums are absolutely beautiful, with a massive cast frame.
I feel in retrospect that another model, the Selenium 15PW3CE might be a better sounding speaker, but I couldn't get over the stamped steel basket. It only costs about $70 from PartsExpress.
It has a sweet freq curve, and I have heard that lower power handling models, generally sound better. As an example look at the Hammer driver: steel frame and lower power capacity. I think it would be worth a try and at that price what have you got t o lose?
I heartilly recommend the Dick Olsher plans, just for the general info. HOWEVER, they are designed for the old Fostex FE 208 model which has been discontinued. Maybe if you guys asked, he will get going on a crossover and notch filter for the new 208. Tell himyou are waitin for the new design before buying!!
I hear you have to have a notch filter on the 208 to tame the big response peaks. The new 208 has only one peak, but a whopper.
I'll try changing Mr. Olshers filter to fit my driver, we'll see.
Mark,
Did you build the cabinets for the Audax driver and then substituted the Selenium driver or did you redesign the bass cabinet for the Selenium driver? I am not sure that just swapping the drivers will work if you do not redesign the bass enclosure and any crossovers used between the bass unit and the Fostex.
Did you build the cabinets for the Audax driver and then substituted the Selenium driver or did you redesign the bass cabinet for the Selenium driver? I am not sure that just swapping the drivers will work if you do not redesign the bass enclosure and any crossovers used between the bass unit and the Fostex.
I used Bass Box to check out the box tuning. Those big drivers don't seem to vary much in how the box size affects them. I am using a bigger box and tube ports instead of a slot like Dick used ,and haven't compared the size of my ports to his. The box is a size that will also work OK sealed, so I might try that too.
Mr. Olsher has commented to me that he tried an Eminence 15" driver and could never get it to integrate well, which put me off the Eminences. They do have some bumps in the respose at the crosover area. The Seleniums are also not as well behaved as the Audax's so it is a risk, but they seem a bit better than the Eminences. I person I have corresponded with used Eminences and is quite happy. Who knows if the Golden eared would approve-I haven't heard them. The Audax's have a nice flat response which goes on forever which I'm sure makes the crossover a lot easier to get right.
OK, both my drivers are different, BUT they turn out not to be too different, so a bit of experimentation might do the trick. I'm sure copying the Olsher plans is a MUCH straighter route to good sound, and the extra cost of the Audaxs might seem cheap after you spend many hours tweaking. I think there are still stocks of the old Fostex drivers around....
Worst case, I have a pair of drivers for the band PA 😉
Mr. Olsher has commented to me that he tried an Eminence 15" driver and could never get it to integrate well, which put me off the Eminences. They do have some bumps in the respose at the crosover area. The Seleniums are also not as well behaved as the Audax's so it is a risk, but they seem a bit better than the Eminences. I person I have corresponded with used Eminences and is quite happy. Who knows if the Golden eared would approve-I haven't heard them. The Audax's have a nice flat response which goes on forever which I'm sure makes the crossover a lot easier to get right.
OK, both my drivers are different, BUT they turn out not to be too different, so a bit of experimentation might do the trick. I'm sure copying the Olsher plans is a MUCH straighter route to good sound, and the extra cost of the Audaxs might seem cheap after you spend many hours tweaking. I think there are still stocks of the old Fostex drivers around....
Worst case, I have a pair of drivers for the band PA 😉
Mark,
Now I understand what you have done, it looks like you have the design under control. I am also working on a similar approach so after you recover from this weekends party, I would like to hear how the speaker system turns out.
Happy birthday
Now I understand what you have done, it looks like you have the design under control. I am also working on a similar approach so after you recover from this weekends party, I would like to hear how the speaker system turns out.
Happy birthday
OK guys, this is an emergency!
Here is a crossover that Selenium uses for their coax speaker that has (duh!) a D205T1 horn driver inside a 15" woofer
I am buying the horn driver and a horn separately to use with my 15" Selenium driver.
Since the horn driver is the same and the woofer is similar to the coax, I feel that this will be acceptable for use to convert my bass boxes to PA duty instead of HI FI use. This is for the fast approaching party mentioned above and I need to order parts ASAP!!!!!!!! So please help me get this thing together so I have a happy birthday
The 1.15 mH inductor on the woofer makes sense in that it will flatten out a rising rate starting around 1000 hz. It also makes sense that there is no further low pass filter because at about 3000 hz the response curve just drops like a cliff, so I think it can be run without further filtering. Actually the woofer I'm using even starts dropping sooner and has less rising rate so could I maybe eliminate this altogether?
Now, on to the horn tweeter network. The 4.7 uF cap makes sense and the 0.3 mH inductor makes sense, but the part with the 1.47 uF cap and 2 resistors in parallel has me confused.
What does the 20/22R resistor designation mean? Why is the cap in parallel with them? I assume the resistors are reducing signal to the tweeter so can I replace them with an 8 ohm L-pad?
If so do I leave the cap in paralel? or just add the value to the 4.7 cap?
Help me and save my party!!!please!!
Here is a crossover that Selenium uses for their coax speaker that has (duh!) a D205T1 horn driver inside a 15" woofer
I am buying the horn driver and a horn separately to use with my 15" Selenium driver.
Since the horn driver is the same and the woofer is similar to the coax, I feel that this will be acceptable for use to convert my bass boxes to PA duty instead of HI FI use. This is for the fast approaching party mentioned above and I need to order parts ASAP!!!!!!!! So please help me get this thing together so I have a happy birthday
The 1.15 mH inductor on the woofer makes sense in that it will flatten out a rising rate starting around 1000 hz. It also makes sense that there is no further low pass filter because at about 3000 hz the response curve just drops like a cliff, so I think it can be run without further filtering. Actually the woofer I'm using even starts dropping sooner and has less rising rate so could I maybe eliminate this altogether?
Now, on to the horn tweeter network. The 4.7 uF cap makes sense and the 0.3 mH inductor makes sense, but the part with the 1.47 uF cap and 2 resistors in parallel has me confused.
What does the 20/22R resistor designation mean? Why is the cap in parallel with them? I assume the resistors are reducing signal to the tweeter so can I replace them with an 8 ohm L-pad?
If so do I leave the cap in paralel? or just add the value to the 4.7 cap?
Help me and save my party!!!please!!
Attachments
Yeah, I agree with Dave, it is for compensating for a fall off in the tweeters response at higher frequencies.
You could try connecting the XO as is, and if that sounds too bright, bypass the contour element. Bypassing will probably increase overall treble level, depending on the sensitivity of the new HF driver, so you may then need to attenuate it with a resistor.
You could try connecting the XO as is, and if that sounds too bright, bypass the contour element. Bypassing will probably increase overall treble level, depending on the sensitivity of the new HF driver, so you may then need to attenuate it with a resistor.
Boy, great response! Thanks Dave as always for your graphic clean-up and thanks to you and Pinkmouse for the advice (and agreement?!!) what is this board coming to!?
That makes sense about the relative increase of the top end. It also explains how to use those pro drivers that roll off a lot at the top.
1. Since the crossover is for this specific driver I'll bet it works out pretty well, but I'm using a horn lense and the coax uses the woofer cone only so I suspect the horn has better high end?
Maybe it doesn't need the boost. Man I realize I'm reallly guessing here!!
2. About those resistors: are they a spec of 20 ohm to 22 ohm resistors ? or something else? I'd hate to be off by an order of magnitude!! DO people ever run the bass drivers full range and let the driver roll itself off? (I know we do this in Hi Fi sometimes)
Yaaaa for DIY Audio, they saved the party!
That makes sense about the relative increase of the top end. It also explains how to use those pro drivers that roll off a lot at the top.
1. Since the crossover is for this specific driver I'll bet it works out pretty well, but I'm using a horn lense and the coax uses the woofer cone only so I suspect the horn has better high end?
Maybe it doesn't need the boost. Man I realize I'm reallly guessing here!!
2. About those resistors: are they a spec of 20 ohm to 22 ohm resistors ? or something else? I'd hate to be off by an order of magnitude!! DO people ever run the bass drivers full range and let the driver roll itself off? (I know we do this in Hi Fi sometimes)
Yaaaa for DIY Audio, they saved the party!
Variac said:
what is required in the end is an r of 10 to 11 ohms that handles 40 W. Yes i'm sure some will let the bass drivers roll offf naturally.
dave
Party/High Fi Speaker update
I feel a report is due on my Basszilla Box party speakers
Dave and Pinkmouse explained the shaping elements of the crossover and I realized that this resistor/cap part of the crossover would boost the low end of the the tweeter as well as the upper. (of course this boost might be lower than the subsequent crossover allows to pass, but I just thought of this possibility!!)
Back then I just thought that here we are boosting the lower end of the tweeter as well as the upper end in order to get more high end response. Then I noticed the inductor as the bass crossover which would only be rolling off the woofer by 6 dB, in effect only cancelling out the excessive boost in the lower tweeter range. BUT wait! I got the crossover design from a co-ax configuration. My tweeter will have a horn instead of just using the cone of the woofer. This should have better high end...
So, by this convuluted excuse-making I was able to justify leaving out the tweeter shaping circuit because I would already have better high end, and leave out the woofer inductor because I'm not increasing the tweeter response in the crossover region. Also, more importantly, the woofer just drops off very steeply around 3k anyway-a lot steeper than almost any crossover, just about where the recommended horn driver crossover cuts off.
So anyway, I threw the box together using two thickneses of 11 ply agathis front and back, and one thickness on the sides. One cross brace about 40 % of the way from the floor. Basically the dimensions Dick Olsher recommends for the Basszilla, but 15.5 inches deep instead of 12". I used the aforementioned bracing as well as 2 2x2 s running front to back in the lower section. He doesn't use any bracing in his design, but recommends it. So with all this bracing and thicker walls, I ended up with only a little bigger internal volume than he recommends.
The selenium D205Ti horn driver looked really cool sitting on top of the box with a Parts Express 270-099 horn The horn is very thick plastic and only cost $10 - quite a deal I would say. I incorporated an adjustable L-pad into the crossover to tune the thing. Power amp is my stock Hafler D220
OK how did it work? The bass is a revelation, very tight and low distortion. Not as low sounding as I expected as everyone had said the room gain fills in a bit under the 40hz that the box is flat to. The great thing is that all the different bass pitches are clear and distinct. The high end is also very low distortion, so it all fits together rather well. The mid range is a bit less clear, probably because I'm using the 15" driver for a lot of it. Maaabe the mid range is a bit pronounced, but maybe it's just that is a bit woolier than the rest. Overall, the warnings that you hear about pro gear apply. I was listening in front of them and cranked them up to what seemed reasonably loud, but when I tried to yell something to my brother 3 feet away, he couldn't hear a word. It really is possible to easily damage your hearing and not realize you are doing it! Low distortion is a pleasure, but the speaker loses out in the tone department. It sounds clinical, a little cold.
They worked great for party music and as band PA speakers without breaking a sweat. The party was a success with over 75 people. I am now officially 50.
Next step- substitute the Fostex 208's for the horns, I'll be crossing the woofers over at under 200 hz instead of 3000hz so the speaks will sound a lot different. I listened to the Fostexes alone with a tiny baffle. My Mahler 8th cd was finally listenable -no bass of course, but with that huge orchestra, various chorus, organs etc. it had always been a complete mess on other systems. The Fostexes kept everything discernable as separate entitys that make sense, so I'm pretty excited. My first speakers, almost finished and signs that they will be pretty good!!!
MJK:
I certainly wouldn't claim to have the design under control!!!
But I think I have studyied the Olsher design and read up on this site enough that I have a fighting chance. I'll probably be tuniing the things still when I'm 80!!
I feel a report is due on my Basszilla Box party speakers
Dave and Pinkmouse explained the shaping elements of the crossover and I realized that this resistor/cap part of the crossover would boost the low end of the the tweeter as well as the upper. (of course this boost might be lower than the subsequent crossover allows to pass, but I just thought of this possibility!!)
Back then I just thought that here we are boosting the lower end of the tweeter as well as the upper end in order to get more high end response. Then I noticed the inductor as the bass crossover which would only be rolling off the woofer by 6 dB, in effect only cancelling out the excessive boost in the lower tweeter range. BUT wait! I got the crossover design from a co-ax configuration. My tweeter will have a horn instead of just using the cone of the woofer. This should have better high end...
So, by this convuluted excuse-making I was able to justify leaving out the tweeter shaping circuit because I would already have better high end, and leave out the woofer inductor because I'm not increasing the tweeter response in the crossover region. Also, more importantly, the woofer just drops off very steeply around 3k anyway-a lot steeper than almost any crossover, just about where the recommended horn driver crossover cuts off.
So anyway, I threw the box together using two thickneses of 11 ply agathis front and back, and one thickness on the sides. One cross brace about 40 % of the way from the floor. Basically the dimensions Dick Olsher recommends for the Basszilla, but 15.5 inches deep instead of 12". I used the aforementioned bracing as well as 2 2x2 s running front to back in the lower section. He doesn't use any bracing in his design, but recommends it. So with all this bracing and thicker walls, I ended up with only a little bigger internal volume than he recommends.
The selenium D205Ti horn driver looked really cool sitting on top of the box with a Parts Express 270-099 horn The horn is very thick plastic and only cost $10 - quite a deal I would say. I incorporated an adjustable L-pad into the crossover to tune the thing. Power amp is my stock Hafler D220
OK how did it work? The bass is a revelation, very tight and low distortion. Not as low sounding as I expected as everyone had said the room gain fills in a bit under the 40hz that the box is flat to. The great thing is that all the different bass pitches are clear and distinct. The high end is also very low distortion, so it all fits together rather well. The mid range is a bit less clear, probably because I'm using the 15" driver for a lot of it. Maaabe the mid range is a bit pronounced, but maybe it's just that is a bit woolier than the rest. Overall, the warnings that you hear about pro gear apply. I was listening in front of them and cranked them up to what seemed reasonably loud, but when I tried to yell something to my brother 3 feet away, he couldn't hear a word. It really is possible to easily damage your hearing and not realize you are doing it! Low distortion is a pleasure, but the speaker loses out in the tone department. It sounds clinical, a little cold.
They worked great for party music and as band PA speakers without breaking a sweat. The party was a success with over 75 people. I am now officially 50.
Next step- substitute the Fostex 208's for the horns, I'll be crossing the woofers over at under 200 hz instead of 3000hz so the speaks will sound a lot different. I listened to the Fostexes alone with a tiny baffle. My Mahler 8th cd was finally listenable -no bass of course, but with that huge orchestra, various chorus, organs etc. it had always been a complete mess on other systems. The Fostexes kept everything discernable as separate entitys that make sense, so I'm pretty excited. My first speakers, almost finished and signs that they will be pretty good!!!
MJK:
I certainly wouldn't claim to have the design under control!!!
But I think I have studyied the Olsher design and read up on this site enough that I have a fighting chance. I'll probably be tuniing the things still when I'm 80!!
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