Experimenting with High-Pass for P3ESR + KEF LS50 with REL T5i

Discussion in 'Audio Hardware' started by murphythecat, Jun 2, 2017.

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  1. murphythecat

    murphythecat https://www.last.fm/user/murphythecat Thread Starter

    Location:
    Canada
    hi everyone
    I have built a DIY Pass B1 pre amp. with the help of Thorsten Loesch, Ive added a way to have a highpass to one of my Pass b1 output.

    here are the measurements of my P3ESR at the listening position.
    you can see the fullrange measurements and the Highpass measurements with the bass rolling off
    [​IMG]screen shot on pc

    I still connect my REL T5i via high level input and so literraly make the sub battle the highpass. probably not the best solution but my measurements seems to be fine and I still get extension down to 30hz

    the red line here is the P3esr at the LP highpassed and the white line is when I add the REL t5i. pretty happy with the measurements!
    [​IMG]hosting images

    the highpass first obvious advantage is how much louder the P3ESR can play without sounding distress or compressed. this is imo the main problem of the P3esr compared to my SHL5+.

    more experiments to come! this is something I think open up a complete different approach to 2.1 channel as I feel integrating a passive highpass via my Pass b1 is very transparent
     
    Last edited: Jun 2, 2017
  2. Ron Scubadiver

    Ron Scubadiver Forum Resident

    Location:
    Houston TX
    Technically it makes sense. Some subwoofers have an output with a high pass filter.
     
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  3. murphythecat

    murphythecat https://www.last.fm/user/murphythecat Thread Starter

    Location:
    Canada
    I just cant believe what im hearing


    with the P3esr been slightly relieved of the low and sub bass, the mid is more open and much more holographic. I now feel surrounded by the sound and the laid back nature of the p3esr seem gone. im now in the 5th row, before I was in 10th row. voices are coming out of the speakers. the sound is less laid back. its noticably less compressed. more effortless presentation. wow

    the bass is another dimension. im hearing things in the bass that only my jbl lsr32, shl5+ or other big speakers i know well can do. the bass information in everytrack is very present, just like bigger speakers can do so easily. I hear subtle changes in bass. its wonderful.

    since I connect my sub still via highlevel input, the transients are intact and I dont feel the sub is slowing down the sound at all.

    im blown away right now and ill have to compare to my shl5+ asap since it literally transformed the sound.
     
    Last edited: Jun 2, 2017
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  4. pdxway

    pdxway Forum Resident

    Location:
    Oregon, USA
    That is why I am using 2 subs and crossover all my speakers high. :righton:
     
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  5. ls35a

    ls35a Forum Resident

    Location:
    Eagle, Idaho
    We've known for 40 years this is a good, nay, very good idea but no nearly no manufacturer does this.

    I had a Dahlquist electronic crossover sending 80hz and up to my ADS 400's 35 years ago - worked great and those 400's never sounded better.
     
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  6. murphythecat

    murphythecat https://www.last.fm/user/murphythecat Thread Starter

    Location:
    Canada
    I know ls35a. the pity is that there is basically no product right now, unless you buy a subwoofer with built in highpass, that allow the user to experiment.
    I had to build a DIY pass b1 and integrate the 1st order passive highpass via line level.

    I will experiment feeding my REL with the line level input and see if I can get better results, but im afraid line leve input is inferior then hi level input...
     
  7. jupiterboy

    jupiterboy Forum Residue

    Location:
    Buffalo, NY
    Nice work. My speaks go fairly low, but I've seen similar with a rumble filter. Takes the load off the speakers and amp. Also, good to see other real-world in-room measurements.
     
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  8. avanti1960

    avanti1960 Forum Resident

    Location:
    Chicago metro, USA
    murphy-
    looks ok but what is that bass peak at 50 Hz? looks like the high pass could be steeper. do you get the same peak with the LS50s? the LS50s seem to have a built in high pass because they roll off like a rock at their F3 frequency.

    the other thing is that your sub seems to be slightly out of phase with the P3s. Does it have a continuous phase angle adjustment? try adjusting it in 1/4 turns until the response is smoother and has no peaks / valleys. Alternatively try inverting the polarity switch on the sub (if it has one) or just try wiring it reverse phase and see how that measures.
    good start but it can be greatly improved on.
     
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  9. jupiterboy

    jupiterboy Forum Residue

    Location:
    Buffalo, NY
    ^ probably the room.
     
  10. murphythecat

    murphythecat https://www.last.fm/user/murphythecat Thread Starter

    Location:
    Canada
    yeah, the 50hz peak is a room mode. as you can see, the small p3esr that is rated to -3db at 75hz in anechoic chamber measure almost flat to 50hz due to room modes at my listening position.

    nothing I can do about that and ive tried every possible LP and speaker placement, this was the best trade-off in my small 10x14 room.

    the highpass in my pass b1 is 1st order. not sure I want to go steeper then that however since I couldnt use my REL via hi level if the highpass was steeper so its the best compromise (if I want to still be able to connect the REL via hi level, 1st order is my only option).

    I will now try to connect my sub via line level and see if it sounds better

    the rel offer only 180 degree out of phase or phase. I dont have continuous phase control, but when I switch the phase, I have a huge dip so my sub is definitely in phase with my speakers.
    The dip between 65hz and 110hz is room related, not much I can do. I have actually improved it by playing with my REL settings. ill post more measurements once my setup is optimized.
     
  11. murphythecat

    murphythecat https://www.last.fm/user/murphythecat Thread Starter

    Location:
    Canada
    @avanti1960 , you were right! I switched the phase and iirc it measured better that way. ill post my actual measurements.

    Yesterday, ive tried to connect the REL sub via line level rather then the recommended REL hi level input. The line level input, even though it measured quite a bit better, sounded horrendous. never did I hear a REL sub so obviously singing a different tune then the mains. it was like two speaker playing a different bass line, transients were literally mushed. it was literally funny, me and my mate laughed at the sound.
    Ill stick to hi level input as it sounds much better integrated, transients are back and integration is just perfect to my ears.

    Im amazed by how much louder the P3ESR can go: its special to hear what the P3esr are finally able to do. I can have my 50 WPC lm3875 gainclone playing at almost max level and the P3esr are still able to take it! id say that in my small bedroom, the P3ESR highpassed can go as loud as I need. The P3ESR sounds much less compressed and the midrange is now more open and more details are coming thrue.
    My pass b1 with highpass capabilities make me want to re-explore all my small standmounts. ill try the kef ls50 and atc scm7v3 and see which speaker react the best to my new system.

    however, comparing SHL5+ to my highpassed P3ESR + REL T5i, the SHL5+ bass is still more impressive and bigger. is it more accurate, I dont know, but the SHL5+ bass is more fun, more visceral.
     
    Last edited: Jun 6, 2017
  12. jupiterboy

    jupiterboy Forum Residue

    Location:
    Buffalo, NY
    Looks horrible, but sometimes it helps to expand that vert axis.
     
  13. murphythecat

    murphythecat https://www.last.fm/user/murphythecat Thread Starter

    Location:
    Canada
    ok
    I just realized that the dip at 400hz was created by the orientation of my measurements mic. same with the dip at 100hz!

    I now have a extraordinary response at the listening position. my room is well treated but ever since I changed orientation of my room, im quite amazed by my measurements taken about 7 feet away from the speakers:
    the white line is the P3ESR fullrange without subwoofer
    the yellow line is the P3ESR highpassed without subwoofer
    the red line is the P3ESR highpassed with the subwoofer well integrated
    [​IMG]image sharing
    im not sure why I get such a bumped response under 250hz downward, but I guess this is room gain and nothing I can much do

    this is the proof that with some treatment and well understanding on to how to find the best listening position and speaker position, anyone with patience can achieve excellent measurements at the LP
     
    Last edited: Jun 6, 2017
  14. jupiterboy

    jupiterboy Forum Residue

    Location:
    Buffalo, NY
    Big improvement. What did you do to the orientation of the mic?
     
  15. murphythecat

    murphythecat https://www.last.fm/user/murphythecat Thread Starter

    Location:
    Canada
    instead of having it face the ceiling, its now facing the speakers directly.
     
  16. jupiterboy

    jupiterboy Forum Residue

    Location:
    Buffalo, NY
    I've never seen that dramatic a shift, but I'll test a bit more next time I drag out the gear.
     
  17. murphythecat

    murphythecat https://www.last.fm/user/murphythecat Thread Starter

    Location:
    Canada
    I use a behringer ecm8000. its been recommended to me to use it straight up, but now when facing the speakers I get no more dip at 100 and 400hz at the LP. so i guess its the proper way to measure my speakers?
    i do however now get a dip at the XO point around 3.5khz
     
  18. jupiterboy

    jupiterboy Forum Residue

    Location:
    Buffalo, NY
    I use the same mic, but I have a calibrated one for my phone app as well. I usually compare those two.
     
  19. murphythecat

    murphythecat https://www.last.fm/user/murphythecat Thread Starter

    Location:
    Canada
    okay, my measuements keep getting better.

    im officially going mad but playing with subwoofer placement brings huge benefits in this setup.

    with the REL T5i on the floor between the mains, I just couldnt get the subwoofer to fill my dip at 100hz. Ive then decided to put it on the table in between my speakers at the same height of the speakers.

    Results is now its basically flat from 35 hz to 120hz. I no longer haev that dip and the bass have much better fondation. I know I shouldnt have a single sub go as high as 100hz, but what the hell, it sounds much more convincing in the bass and since its right between my mains and at the same height, I dont hear the bass coming from the sub.

    Pics and measurements tomorrow!
     
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  20. beowulf

    beowulf Forum Resident

    Location:
    Chula Vista, CA
    Have you seen the New Record Day review/video of the P3ESR? He's integrating 4 12" GR Research Subs with Rythmik Audio Servo amps in an open baffle H Frame. Looks like a good combo and I can attest that these subs are fast as they can keep up with my Omega single driver speakers. The Rythmik amps are pretty high quality too as they use class A/B MOSFETs rather than class D which are found in a lot of other brands.

     
  21. murphythecat

    murphythecat https://www.last.fm/user/murphythecat Thread Starter

    Location:
    Canada
    i looked at their website and confused abotu hi livel input
    can we connect them the same principle then REL neutrik/hi-level?
     
  22. murphythecat

    murphythecat https://www.last.fm/user/murphythecat Thread Starter

    Location:
    Canada
    here my final measurements at the listening position
    green line is with sub activated
    yellow line is the p3esr with the 1st order highpassed around 100hz
    [​IMG]
     
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  23. pdxway

    pdxway Forum Resident

    Location:
    Oregon, USA
    I continue to play with my setup. Right now instead of 2 subs, I have one in between the speakers, closer to the right speakers. I crossover at 100 Hz and found that 100 Hz sounds the best to me with my setup. My sub is also elevated.
     
  24. Ghostworld

    Ghostworld Senior Member

    Location:
    US

    See if you can live with it forever, though. I just went to a "highly detailed" speaker with less low frequency information and was wowed by HOW MUCH MORE I was hearing. Listen to those things I never noticed before! Two weeks later and my tinnitus starting flaring up from the heightened treble response. A month later and I've dumped the speakers. Some new is always exciting; but try living with it for awhile.
     
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  25. murphythecat

    murphythecat https://www.last.fm/user/murphythecat Thread Starter

    Location:
    Canada
    agreed
    I put my kef ls50 and afte a hour I cant stand them
    the p3esr after a year im sitll happy
     
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