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 Multi-Way Conventional loudspeakers with crossovers

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 25th June 2002, 01:33 AM #1 diyAudio Member     Join Date: Jan 2002 Location: Borås, Sweden, Tellus Sub 0-180° Hi Is there anyone who knows how to build circuit for 0-180° change in phase, it should work from 20-100Hz. TIA Keld __________________ "What is done by what is called myself is, I feel, done by something greater than myself in me." James Clerk Maxwell. 1879
 25th June 2002, 04:34 AM #2 diyAudio Member     Join Date: Jun 2001 Location: Eugene, OR Are you looking for just 0 and 180 degrees or continuously variable from 0 to 180 degrees?
 25th June 2002, 06:31 AM #3 diyAudio Member     Join Date: Jan 2002 Location: Borås, Sweden, Tellus Hi I'm looking for a continuously variable. I want it for an active highpass/lowpass/eq thing I'm building. Keld __________________ "What is done by what is called myself is, I feel, done by something greater than myself in me." James Clerk Maxwell. 1879
 25th June 2002, 09:29 AM #4 diyAudio Member     Join Date: Sep 2001 Location: Sydney Keld, is a base circuit diagram that you might find interesting. It can contnuously change phase from 0 to 180; from 20Hz +. It is an all pass circuit with the response being -180degrees at the circuit's resonant frequency, Fo. V1 = input test voltage Rl = output test load (open circuit) R3 = R4 = R5 = R6 = 10k-ohm potentiometers (R) R7 controls the shape of the curve C1 = C2 = 0.8uF capacitors (C) Fo = 1/(2*pi*R*C) so when all potentiometers are: R -- Fo 10k -- 20Hz 5k -- 40Hz 2.5k -- 80Hz ... is a simulation of the circuit above. hope this helps __________________ Crossover/Subwoofer Simulator
 25th June 2002, 12:05 PM #5 diyAudio Member     Join Date: Jan 2002 Location: Borås, Sweden, Tellus Thanks a lot. I will check it out later (now its lunchbreak). It seems to be what i am looking for. BBL Keld. __________________ "What is done by what is called myself is, I feel, done by something greater than myself in me." James Clerk Maxwell. 1879
 26th June 2002, 10:33 AM #6 diyAudio Member     Join Date: Jan 2002 Location: Kuopio, Finland Hi, I think that Mr. Linkwitz has quite simpler all-pass realization, http://www.linkwitzlab.com/filters.htm#4 namely. It is labeled as time delay, but that is what is needed here anyway.. Regards, Janne
 26th June 2002, 02:09 PM #7 diyAudio Member   Join Date: Feb 2001 Location: Estonia f4ier As can be seen from the simulation of the circuit you provided the output voltage of the system (that is subwoofer loudness) will change whenever the phase is adjusted. Usually one can check the correct phase of the subwoofer without measurement system by ear adjusting the phase until the sub sounds loudest at the listening place but with this circuit it becomes quite inconvenient? Argo
 26th June 2002, 02:30 PM #8 diyAudio Member     Join Date: Sep 2001 Location: Sydney Janne, Mr. L has got some pretty simple circuits there argo, I've simulated potentiometer (R3, R4, R5 and R6) settings of 10k, 5k and zero. The blue flat line is one of three while the other two are practically value-by-value equal to the blue flat line -- that's why you don't see them Between zero and 10k potentiometer settings the output voltage remains constant, even up to about 10kHz, given the pictured parts, if I can recall. What you see changing with frequency and potentiometer setting is the phase. You can simulate the circuit for yourself, the student version of PSPICE is free from www.orcad.com hope this has cleared things up __________________ Crossover/Subwoofer Simulator
 26th June 2002, 02:40 PM #9 diyAudio Member   Join Date: Feb 2001 Location: Estonia f4ier That makes a difference. I dint look the graph carefully enough –that is a phase line changing there of course. I'll certainly try to do some sims. Sorry for misleading post. Argo
 27th June 2002, 10:39 PM #10 diyAudio Member     Join Date: Jan 2002 Location: Borås, Sweden, Tellus Hi f4ier Now i have had a closer look at the circuit and sim you posted. It does a little more than I need. I only need 0-180 "twist " in the crossover region (100? Hz) , and If I understand it right it must have a 4-gang 10k pot Janne Thanks for the link it look very good and simple, but I need and adjustable, but maybe it is possible to make it do that. After looking at the two circuits suggested to me, i came to the conclusion that I have to learn to do sims, so I downloaded Pspice Student version, and in a year or two when I learned to use it I will build my 0-180 thingy Keld __________________ "What is done by what is called myself is, I feel, done by something greater than myself in me." James Clerk Maxwell. 1879