Hi Sreten, many thanks!
Re: (quote) "The phase changes are not abrupt at all, its the way its graphed." Oops, the frequency is logarithmic scale! So I guess its a smooth transition! Correct?
and (quote): "However you have shown the acoustic phase, the issue is the electrical phase." Um, but I thought the 'issue' was the acoustic response? Where am I going wrong here? please?....grant (perplexed)
Re: (quote) "The phase changes are not abrupt at all, its the way its graphed." Oops, the frequency is logarithmic scale! So I guess its a smooth transition! Correct?
and (quote): "However you have shown the acoustic phase, the issue is the electrical phase." Um, but I thought the 'issue' was the acoustic response? Where am I going wrong here? please?....grant (perplexed)
Sreten, Hi
Re: (quote): 4th order = 360 degrees stopband
etc...The higher the order, the more phase change you get, the "worse" the transient response becomes - away from the "ideal" behaviour."
But wouldn't 4th order be effectively 0 degrees? I.e. 0=360 degrees?
Would transient response become un-ideal then? Help! lol, grant
Re: (quote): 4th order = 360 degrees stopband
etc...The higher the order, the more phase change you get, the "worse" the transient response becomes - away from the "ideal" behaviour."
But wouldn't 4th order be effectively 0 degrees? I.e. 0=360 degrees?
Would transient response become un-ideal then? Help! lol, grant
Dear Sreten, all I'm trying to do is to understand! If I can learn from you , that would be fantastic! Any help you kindly give me is immensely appreciated! best regards and a very merry Xmas!, grant
Hi,
In terms of blowing up amplifiers we are talking load impedance.
Impedance is real (resistive) and imaginery (complex).
Z = real x cos phase angle + imag x sin phase angle.
Low Z with high imaginery part cooks amplifiers.
Use the impedance meter function of TinaTi.
+ 180 = - 180 so + 270 degrees is shown as - 90, its still + 270.
360 is not zero, 450 is not 90, its still + 450 degrees.
You can see the c/o below can be analysed in two stages.
🙂/sreten.
P.S. what is the Answer ?
In terms of blowing up amplifiers we are talking load impedance.
Impedance is real (resistive) and imaginery (complex).
Z = real x cos phase angle + imag x sin phase angle.
Low Z with high imaginery part cooks amplifiers.
Use the impedance meter function of TinaTi.
+ 180 = - 180 so + 270 degrees is shown as - 90, its still + 270.
360 is not zero, 450 is not 90, its still + 450 degrees.
You can see the c/o below can be analysed in two stages.
🙂/sreten.
P.S. what is the Answer ?
Attachments
After a bit of simplifying and removing some additional zobels, I tried to reinstate a single one to the mid - and that was something of a miracle
Its the second zobel with 2.2uF/8R2 in question
You are welcome to sim it, if you like - it probably wont look very good, but it sure sounds good 🙂
Its the second zobel with 2.2uF/8R2 in question
You are welcome to sim it, if you like - it probably wont look very good, but it sure sounds good 🙂
Attachments
Sreten, thanks so much!
I am SO pleased you put up that schematic, now I have a start for a series/parallel network!
I really appreciate your guidance and effort/time in creating it. Thank you. I still have many problems of course - and I'm certainly not a mathematition. Also, thanks again for your TinaTi link.
The real/imaginery info does 'ring a bell' with me, but unfortunately I'm so vague on that now. (so long ago)
I'm wondering if this could somehow be , (not sure about this), possibly related to a 'best/worse' case *practical scenario*? I realise the theory is very complex and probably beyond my ability.
By 'related', I mean to say is, could the theory be somehow easily transferred into practicality?
Re: quote: "360 is not zero", In light of your comments, there are other factors. Again it seems cookbook stuff is a delusion. Superficially, is why I believed it, but to a beginner 0 does look like 360!
I will investigate your suggested xo as best I can, and hope you continue to help me out. I'd still like to find more references on series xo's, other than the two I already have.
Re: "P.S. what is the Answer ?" 42 of course! haha! grant
I am SO pleased you put up that schematic, now I have a start for a series/parallel network!
I really appreciate your guidance and effort/time in creating it. Thank you. I still have many problems of course - and I'm certainly not a mathematition. Also, thanks again for your TinaTi link.
The real/imaginery info does 'ring a bell' with me, but unfortunately I'm so vague on that now. (so long ago)
I'm wondering if this could somehow be , (not sure about this), possibly related to a 'best/worse' case *practical scenario*? I realise the theory is very complex and probably beyond my ability.
By 'related', I mean to say is, could the theory be somehow easily transferred into practicality?
Re: quote: "360 is not zero", In light of your comments, there are other factors. Again it seems cookbook stuff is a delusion. Superficially, is why I believed it, but to a beginner 0 does look like 360!
I will investigate your suggested xo as best I can, and hope you continue to help me out. I'd still like to find more references on series xo's, other than the two I already have.
Re: "P.S. what is the Answer ?" 42 of course! haha! grant
Hi Sreten,
I'm not sure whether its wise to post this, oh well, here goes!
regarding your circuit....could the following be correct?
( I may need some help here!, with my assumptions)....
1) the tweeter HP looks like a standard 2nd order electrical with LPad,
2) the mid HP is replaced with a parallel trap filter otherwise 'standard 2nd' LP and attenuation resistor,
3) the woofer is still effectively parallel 2nd order elect. albeit redrawn?
Now, I assume, all 3 drivers are wired 'schematically in phase', ie + at the top. If this is correct so far, then would the negative 'leg' for tweeter/mid as shown, put the woofer in effectively reversed polarity?
So, despite the difference between the mid's HP and parallel-trap, is it not otherwise a different way of drawing a 'full 2nd order' with woofer inverted? I'm probably leaving myself open here! lol Well, 'you gotta make mistakes to learn' or could it be that there is some sense in the above? thanks, grant
(btw, is 'the answer' Rz meaning I assume Rzobel?)
I'm not sure whether its wise to post this, oh well, here goes!
regarding your circuit....could the following be correct?
( I may need some help here!, with my assumptions)....
1) the tweeter HP looks like a standard 2nd order electrical with LPad,
2) the mid HP is replaced with a parallel trap filter otherwise 'standard 2nd' LP and attenuation resistor,
3) the woofer is still effectively parallel 2nd order elect. albeit redrawn?
Now, I assume, all 3 drivers are wired 'schematically in phase', ie + at the top. If this is correct so far, then would the negative 'leg' for tweeter/mid as shown, put the woofer in effectively reversed polarity?
So, despite the difference between the mid's HP and parallel-trap, is it not otherwise a different way of drawing a 'full 2nd order' with woofer inverted? I'm probably leaving myself open here! lol Well, 'you gotta make mistakes to learn' or could it be that there is some sense in the above? thanks, grant
(btw, is 'the answer' Rz meaning I assume Rzobel?)
Hi Sreten,
Merry Christmas! And many thanks. Its a busy time of the year, I'm reading your reply with MUCH interest and hope to make a sensible reply tomorrow? THANKS, (series are confusing!) grant
Hi Omni, and Tinitus, best regards to you both too!
<*off-topic*> I hope to buy and learn an alto-saxophone one day!
hehe, practicing by the Pacific Ocean - 500 metres away - what a blast! Look out Candy Dulfer! (well u gotta dream!)
Merry Christmas! And many thanks. Its a busy time of the year, I'm reading your reply with MUCH interest and hope to make a sensible reply tomorrow? THANKS, (series are confusing!) grant
Hi Omni, and Tinitus, best regards to you both too!
<*off-topic*> I hope to buy and learn an alto-saxophone one day!
hehe, practicing by the Pacific Ocean - 500 metres away - what a blast! Look out Candy Dulfer! (well u gotta dream!)
Hi everyone, I'm back! Is anyone still here?
..Omni.., I've been reading Troels Gravesen's site , specifically his '3way Classic' design. The mid is a true midrange, a Seas MCA12RC, which Troels praises for its transient response etc. The response
seems pretty good from 400 to 4000, especially the off-axis compared to the CA15RLY (see the attached). Also it appears to have less of a 'dip' problem, so maybe I have finally found a suitable mid-driver for my system?
With 'idealised' xo-points at 400 and 4kHz, I feel a little optimistic that my other drivers could work in a full 1st order electrical xo. If not a 27TDFC upgrade ( 4k-1st ) would be ok , I think..... Any ideas? thanks, grant
..Omni.., I've been reading Troels Gravesen's site , specifically his '3way Classic' design. The mid is a true midrange, a Seas MCA12RC, which Troels praises for its transient response etc. The response
seems pretty good from 400 to 4000, especially the off-axis compared to the CA15RLY (see the attached). Also it appears to have less of a 'dip' problem, so maybe I have finally found a suitable mid-driver for my system?
With 'idealised' xo-points at 400 and 4kHz, I feel a little optimistic that my other drivers could work in a full 1st order electrical xo. If not a 27TDFC upgrade ( 4k-1st ) would be ok , I think..... Any ideas? thanks, grant
Attachments
Hi Sreten, sorry for the long delay!
Although I can't say that I really understand this in an 'electrical-sense'... 'quote': "[Yup, you are confused, notice the mid/treble section is wired across the inductor, in a 2nd order LP they would not be]" It does seem to make some logical? sense to me (maybe?), and I'm very happy with your other corrections! Thanks so much indeed!
I'm also reading Andrew's fascinating thread "Series Crossover for Zaph's L18/27TBFCG Design?", in the hope of a better 'series-understanding'.
Btw, (just for interest), would you by chance have any comments on the Seas MCA12RC in relation to my 3way in my previous post? Many thanks, grant
Although I can't say that I really understand this in an 'electrical-sense'... 'quote': "[Yup, you are confused, notice the mid/treble section is wired across the inductor, in a 2nd order LP they would not be]" It does seem to make some logical? sense to me (maybe?), and I'm very happy with your other corrections! Thanks so much indeed!
I'm also reading Andrew's fascinating thread "Series Crossover for Zaph's L18/27TBFCG Design?", in the hope of a better 'series-understanding'.
Btw, (just for interest), would you by chance have any comments on the Seas MCA12RC in relation to my 3way in my previous post? Many thanks, grant
Hi,
Think of it this way :
1st order parallel has components is series with the drivers, with the two sections in parallel.
1st order series has the components in parallel with the drivers with the two sections in series.
Also consider the MCA15RCY (see TM's PMS - poor mans strad).
🙂/sreten.
Think of it this way :
1st order parallel has components is series with the drivers, with the two sections in parallel.
1st order series has the components in parallel with the drivers with the two sections in series.
Also consider the MCA15RCY (see TM's PMS - poor mans strad).
🙂/sreten.
Grant, It definately looks like a driver that will provide less headaches than the CA15RLY, and it appears that you have stopped at nothing to do your due diligence, a trait I respect........I don't know where you are at on the tweeter, but the TDFC has gotten great reviews, so you mignt seriously consider it..........If your gonna get a midrange you are very optimistic about, don't stop there. Invest in a tweeter that will compliment your new find. You have been very supportive in my endeavors, and should you decide on the new midrange, my offer still stands to run your drivers through the FRC tools to provide you files for your crossover simulation................Respectfully...........Omni
Hi Sreten!
Your explanation "Think of it this way :......." is almost too easy! lol Many thanks!
Also, I'll check Troels' P.M.S. MCA15 to see how it compares to its 'little brother'. Would either of these two (the MCA12 or 15), be the best candidates wrt best performance per least (to moderate) price
in your opinion? Thanks, grant
Your explanation "Think of it this way :......." is almost too easy! lol Many thanks!
Also, I'll check Troels' P.M.S. MCA15 to see how it compares to its 'little brother'. Would either of these two (the MCA12 or 15), be the best candidates wrt best performance per least (to moderate) price
in your opinion? Thanks, grant
Hi,
MCA15 has higher SPL but MCA14 seems more linear, as it often is
Diskussions seem to indicate that the new tweeter reference could be the Peerless HDS tweeter
Another pricerange, but RAW Acoustics has a new very interesting 6" driver (hemp/adire)- could be interesting with multiple drivers in a 2.5-way
Omni, how are you doing - will your speakers be playing soon 🙂
MCA15 has higher SPL but MCA14 seems more linear, as it often is
Diskussions seem to indicate that the new tweeter reference could be the Peerless HDS tweeter
Another pricerange, but RAW Acoustics has a new very interesting 6" driver (hemp/adire)- could be interesting with multiple drivers in a 2.5-way
Omni, how are you doing - will your speakers be playing soon 🙂
Hi Omni!,
Thanks, at first glance the MCA12 looks good except for the 10k peak, but hopefully that will be sufficiently down after simming. I hope the '12' and '15' are available here in Oz! Troels gave the '12' a great 'rap', so it will be interesting to see his opinion of the '15' in comparison. I would have to somehow 'pad-out' the existing mid baffle-cutout-hole to use the '12', as the D75 is wider.
Yes the TDFC's 'look' great and do I intend to get them at some stage. (I'm still struggling to afford the mids! Times are tough...LOL). I don't think there would be any point now in changing to the Alu TBFCG's as I mentioned earlier.
Many thanks for your kind offer re the FRD tools. I might just take you up on that when I decide on which mids and availability here. I wouldn't want you to go to all the trouble if I couldn't get them! Best regards, grant
Thanks, at first glance the MCA12 looks good except for the 10k peak, but hopefully that will be sufficiently down after simming. I hope the '12' and '15' are available here in Oz! Troels gave the '12' a great 'rap', so it will be interesting to see his opinion of the '15' in comparison. I would have to somehow 'pad-out' the existing mid baffle-cutout-hole to use the '12', as the D75 is wider.
Yes the TDFC's 'look' great and do I intend to get them at some stage. (I'm still struggling to afford the mids! Times are tough...LOL). I don't think there would be any point now in changing to the Alu TBFCG's as I mentioned earlier.
Many thanks for your kind offer re the FRD tools. I might just take you up on that when I decide on which mids and availability here. I wouldn't want you to go to all the trouble if I couldn't get them! Best regards, grant
If you want a nice and cheap mid, this Tangband might be worth looking at
http://www.tb-speaker.com/detail/1230_04/w4-1129c.htm
http://www.tb-speaker.com/detail/1230_04/w4-1129c.htm
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