This is my latest idea
I have been through lots of considerations with various horns/compression drivers and 12" woofers and more
But I think I like this one better...its simple and quite cheap
It consists of Beyma AMT ribbon and 4x Eminence BETA-8
2.5way...300/1khz...natural rolloff at around 100hz in closed
May be a combination of passive and active
"Subwoofer" will be something 18" with digital XO/EQ with "gain"
Do you like it or not, or have other options in line with this
any comments are welcome
I have been through lots of considerations with various horns/compression drivers and 12" woofers and more
But I think I like this one better...its simple and quite cheap
It consists of Beyma AMT ribbon and 4x Eminence BETA-8
2.5way...300/1khz...natural rolloff at around 100hz in closed
May be a combination of passive and active
"Subwoofer" will be something 18" with digital XO/EQ with "gain"
Do you like it or not, or have other options in line with this
any comments are welcome
Attachments
I like the form factor you chose because i recently built a pair of H-Frames using Alpha 15's and use towers behind (soon to be beside similar to your sketch).
I know they are more money but check out these 8" Eminence drivers.
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=290-508
Two per side to make 8ohm or they have another one...
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=290-507
The second one is 8ohm so you can use 4 like your sketch but i don't like how it doesn't go as high as the 16ohm driver.
Overall, i do like your idea and think it could be pretty much ideal as far as achieving overall performance from top to bottom.
Godzilla
I know they are more money but check out these 8" Eminence drivers.
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=290-508
Two per side to make 8ohm or they have another one...
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=290-507
The second one is 8ohm so you can use 4 like your sketch but i don't like how it doesn't go as high as the 16ohm driver.
Overall, i do like your idea and think it could be pretty much ideal as far as achieving overall performance from top to bottom.
Godzilla
I would be highly tempted to try 2 modded Fostex 206/207s (removed whizzer cone and phase plug) as dedicated midrange drivers with Beyma AMT's.
Btw, have you noticed the impedance of the AMT's? Although they're specified as 8Ohms drivers, the impendance is basically a flat line at the nominal 4.93 Ohm dc resistance. And only goes over 5 Ohms (to 5.1 Ohms) once in the audible range, so it'll be much more precise to name them 5 Ohm drivers.
Btw, have you noticed the impedance of the AMT's? Although they're specified as 8Ohms drivers, the impendance is basically a flat line at the nominal 4.93 Ohm dc resistance. And only goes over 5 Ohms (to 5.1 Ohms) once in the audible range, so it'll be much more precise to name them 5 Ohm drivers.
For 1kHz xover, I'd like to have a bigger midbass -- 12" or even 15", and one is more than enough (instead of 3). Also, this can be a 'clean' 2 way instead of 2.5way.
I'm very interested in the Beyma, too. If anything is really built around it, please share. 🙂
I'm very interested in the Beyma, too. If anything is really built around it, please share. 🙂
the crossover
I would aim for midrange drivers that are good up to 3khz rather then down at 1khz, and with what size ofdrivers you are using a hybrid 3 way crossover would be a better choice.
at 750 and 3khz would be my choice and you only need 2 midway and I would use them in parallel with a load stablizing resitor in the circuitry and separate tuned boxes. Aim for 92 or 93 db smooth.
I would aim for midrange drivers that are good up to 3khz rather then down at 1khz, and with what size ofdrivers you are using a hybrid 3 way crossover would be a better choice.
at 750 and 3khz would be my choice and you only need 2 midway and I would use them in parallel with a load stablizing resitor in the circuitry and separate tuned boxes. Aim for 92 or 93 db smooth.
I know this is a bass guitar speaker, but I have thought about crossing it at 3khz to make some vocal/guitar PA speakers as it looks pretty good on the graph, and could be used sealed to cross to a sub:
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=290-495
Would the whizzer help with beaming?
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=290-495
Would the whizzer help with beaming?
Thanks fore interest
All suggestions are good and valid
I have been through them all of them, and some more, before I came to this one
Due to the low cost of the BETA-8 its almost cost effective
I could continue about my design criteria, but it will only be very long and boring
Well, it will take a while before Im able to make the saw dust, so things may change before that, and no price of the waveguide AMT yet
edit
The last few days have been awfull
I began to simplify my 3way crossover, and sound did improve significantly with each component removed
Unfortunately I experienced severe and ear hurting phase issues
I almost gave up completely, until I began to experiment with driver polarity
And magic happened
Tweeter xo is still 12db with a Fs-notch and zobel, the whole shabang
But woofers and mid are scaringly simple
Pure "6db" with notches
No zobels or other paralel components, apart from the notches
Sounds so smooth and natural as ever, no artefacts what so ever
Man, do I fell lucky...I thought my days were over
🙂
btw
With such simple xo with only series components its quite interesting and funny to experience how the woofer change when mounting any component on the mid, and vice versa
Interaction between the drivers and related xo is clearly audible
All suggestions are good and valid
I have been through them all of them, and some more, before I came to this one
Due to the low cost of the BETA-8 its almost cost effective
I could continue about my design criteria, but it will only be very long and boring
Well, it will take a while before Im able to make the saw dust, so things may change before that, and no price of the waveguide AMT yet
edit
The last few days have been awfull
I began to simplify my 3way crossover, and sound did improve significantly with each component removed
Unfortunately I experienced severe and ear hurting phase issues
I almost gave up completely, until I began to experiment with driver polarity
And magic happened
Tweeter xo is still 12db with a Fs-notch and zobel, the whole shabang
But woofers and mid are scaringly simple
Pure "6db" with notches
No zobels or other paralel components, apart from the notches
Sounds so smooth and natural as ever, no artefacts what so ever
Man, do I fell lucky...I thought my days were over
🙂
btw
With such simple xo with only series components its quite interesting and funny to experience how the woofer change when mounting any component on the mid, and vice versa
Interaction between the drivers and related xo is clearly audible
Attachments
Thumbs up - for your early testing - not that much about the Beyma AMT available yet!
If you find your tweeter to be stressed too much by the 1 kHz XO - and are willing to throw in some more money - I'd suggest you to try Troels JA8008 - its smooth all way up.
Crossover would become more complicated though to avoid excesive beaming (too many drivers for higher XO).
Michael
If you find your tweeter to be stressed too much by the 1 kHz XO - and are willing to throw in some more money - I'd suggest you to try Troels JA8008 - its smooth all way up.
Crossover would become more complicated though to avoid excesive beaming (too many drivers for higher XO).
Michael
mige0 said:
Thanks Michael
When you write "early testing" I may have confused you a bit
The crossover trouble I descibe is with my present speaker, and not with the AMT project I suggest here
Im still strugling with xo phase issues, though it seems Im very close to a good result
Regarding the 2.5way WWWTW, AMT with BETA-8, I have second thoughts
The AMT is quite big(height), and based on that Im in doubt about about the WTW top section...the two Beta-8 may be too far apart from each other
I am considering a simpler WWT 2.5way, and I am searching fore a good mid/midwoofer
Beta-8 may still be a good option
I have looked closely on Beymas, but all the 8" rated at 95db all seems to be more like 90db with "hickups" 😡
I have contacted ECOnoline about their 8" Afficionade, but no reply, but it will probably be too expencive anyway
Also looking at Supravox 215GMF, but also expencive
All very far from the cheap and good looking Beta-8
I actually at first didnt choose the Beta-8 solely on its price, but think it looks pretty good quality
Hard to see what justifies the much higher price on the other drivers
Ahh, so I misunderstood - but anyway let us know about any of your impressions with the AMT.
Don't worry about the heavy spacing of the 8" speakers - just give it a try - especially if you use e'm all in (series-) parallel.
I use the 8" JA8008 - and before that the 6.5" B&C also - above and below an AMT roughly with the same spacing as yours. No problem whatsoever to my ears.
I do it in power split technique though - hence no additional SPL gain at the XO crossing over to the AMT - but less load per speaker towards lower frequencies.
You could try this trick in passive as well - and as you have 4 speakers each side you could do it twice:
One is the "top" speaker (crossing to the AMT at 1000Hz) getting paralled by another one at slightly lower frequencies (lets say at about 7-800Hz ) and that two paralleld by the other two (lets say at about 4-500Hz ).
This way you get two times a (very) roughly half cut in excursion from 1000Hz down to 300Hz .
Just a little experiment if you already did your setup.
Again the Beta's are a bargain - you won't loose much if you don't look any further and just give it a try.
The JA8008 I suggest (as almost nobody seems to have posted about it) present music with a really beautiful personality, high resolution for details emphasizing not compromizing the sound experience as a whole, vivid, great tonality, room filling, easing to fall into the flow of beat and harmonics.
Just read the interview with Troels Gravesen - I'd say he luckily was able to transferr a considerable amount of his own friendly personality into the JA8008 speaker he developed.
http://aventhusiast.com/audio/interviews/interview-troels-gravesen
Michael
Don't worry about the heavy spacing of the 8" speakers - just give it a try - especially if you use e'm all in (series-) parallel.
I use the 8" JA8008 - and before that the 6.5" B&C also - above and below an AMT roughly with the same spacing as yours. No problem whatsoever to my ears.
I do it in power split technique though - hence no additional SPL gain at the XO crossing over to the AMT - but less load per speaker towards lower frequencies.
You could try this trick in passive as well - and as you have 4 speakers each side you could do it twice:
One is the "top" speaker (crossing to the AMT at 1000Hz) getting paralled by another one at slightly lower frequencies (lets say at about 7-800Hz ) and that two paralleld by the other two (lets say at about 4-500Hz ).
This way you get two times a (very) roughly half cut in excursion from 1000Hz down to 300Hz .
Just a little experiment if you already did your setup.
Again the Beta's are a bargain - you won't loose much if you don't look any further and just give it a try.
The JA8008 I suggest (as almost nobody seems to have posted about it) present music with a really beautiful personality, high resolution for details emphasizing not compromizing the sound experience as a whole, vivid, great tonality, room filling, easing to fall into the flow of beat and harmonics.
Just read the interview with Troels Gravesen - I'd say he luckily was able to transferr a considerable amount of his own friendly personality into the JA8008 speaker he developed.
http://aventhusiast.com/audio/interviews/interview-troels-gravesen
Michael
Tinitus,
G. Pimm uses a similar idea, there are some differences, his config., is TWW, tweeter is Hi-VI 8 and woofer is Eminence 8A like yours, the x-over is much higher at around 4-5Khz. He uses the natural x-over of Beta 8 to cross at 4-5Khz. There is no break up of the cone. The overall system spl=95dB
I don't know very much about AMT tweeter crossing at 1Khz can be too low?
I am considering of using G.Pimm approach.
G. Pimm uses a similar idea, there are some differences, his config., is TWW, tweeter is Hi-VI 8 and woofer is Eminence 8A like yours, the x-over is much higher at around 4-5Khz. He uses the natural x-over of Beta 8 to cross at 4-5Khz. There is no break up of the cone. The overall system spl=95dB
I don't know very much about AMT tweeter crossing at 1Khz can be too low?
I am considering of using G.Pimm approach.
mige0 said:
ttan98 said:
Thanks to both of you, I really appreciate your valid suggestions, very positive
And its quite comforting to know that we can recommend a nice design like the JA8008
Yes, Iam also not so certain about a 1khx xo point of a Beyma AMT
But in that respect its comforting to know that Beta-8 can manage quite a bit more of the highs
And yes, your suggestion with a simpler WWT design with a higher xo point and a Hivi planar have crossed my mind too
Its still attractive 95db sensitivity, and quite a money saver
Thanks again, I havent decided on anything yet, so its really valuable information to me 🙂
Thinking about a stacked modular design
Would be easier to try different configurations, and holds other advantages as well, such as varying angles on each driver
Drawing is not so nice or accurate, but should show the principle clearly enough
You may have seen similar elsewhere
🙂
Would be easier to try different configurations, and holds other advantages as well, such as varying angles on each driver
Drawing is not so nice or accurate, but should show the principle clearly enough
You may have seen similar elsewhere
🙂
Attachments
I made a 2 1/2-way 2x12" using the Beyma TPL 150 (without the horn) and Beyma 12P1000. The TPL's freq response is easier to handle without the horn, but it cant go to 1 kHz. I cross over at 1.2 kHz. With the horn, I guess you could run it down to 7-800 Hz or so.
The 12" Beyma's sound amazingly clean in the midrange, a big surprise for me. 98 dB system sensitivity is nice, but its a bit bass-shy, so you'll need a sub.
I'm working on a 2x15" version also, with the hornloaded TPL150 this time. The main targets are to cross over lower, and to get more bass than the 2x12 version.
A pic of my speaker here:
Measurement...
The 12" Beyma's sound amazingly clean in the midrange, a big surprise for me. 98 dB system sensitivity is nice, but its a bit bass-shy, so you'll need a sub.
I'm working on a 2x15" version also, with the hornloaded TPL150 this time. The main targets are to cross over lower, and to get more bass than the 2x12 version.
A pic of my speaker here:
An externally hosted image should be here but it was not working when we last tested it.
Measurement...
An externally hosted image should be here but it was not working when we last tested it.
Since we're talking about the Beyma TPL150, I'd like to show a measurement comparison of the horn loaded version and the regular version. The highest curve is the horn version. Both measurements are without baffle. The regualr version extends a little more below 2 kHz with a wide baffle, and I expect the horn version would benefit from a baffle as well.
Attachments
Thank you for that information. I've been curious about this driver for some time, especially with the horn, but so far have not seen the horn available for sale anywhere nor any data but from the factory. I think I'll save for a pair for the project after the current one.StigErik said:
PS: do you have H and V polars by any chance?
The horn loaded TPL150H is quite new, its been available from the factory for 2-3 months or so. Expect the retail price to be 20-25% above the TPL150.
Will do some off-axis measurements as soon as I can.
Will do some off-axis measurements as soon as I can.
Hi StigErik,
May I ask how the TPL150Hs sound relative to the Mundorf AMTs?
Thanks!
Best regards
Peter
May I ask how the TPL150Hs sound relative to the Mundorf AMTs?
Thanks!
Best regards
Peter
I have not compared them well enough to say if their sonic differences are just because of different frequency response or not. I have used the Mundorf with a lot of EQ to get it flat within +/- 1 dB, but I have not done that with the Beyma yet. I've also tested the two drivers using very different midrange drivers, which of course will affect the overall impression. So - until I test them in two similar systems with the same frequency response, I dont want to conclude too much!pk said:
That being said - I think they have a lot in common sonically. Both are very free from coloration, and the dynamic qualities just cannot be matched by ribbons or domes.
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