• 01-01-2005, 06:24 PM
    knac67
    Ar Diy Speaker Adjustments
    I am new to DIY speaker building. I have just built the ar.com speakers.They have the current modifications from madisound. I am looking for a little brighter high end.Could somebody recomend the correct mod for the crossovers to acheive this?
    Thank you for the replys,
    chris
  • 01-01-2005, 07:31 PM
    jbandpc
    Un-Adjustment
    Did you add the optional resistor on the tweeter? If so, take it off. I can't imagine wanting more high end than this speaker without that resitor.

    Philip
  • 01-01-2005, 11:24 PM
    knac67
    I just installed the pre-built crossover, it might have been installed. I will check tomorrow..

    Thank you for the tip.
    Chris
  • 01-02-2005, 07:19 AM
    jbandpc
    I'm pretty sure that pre-built one doesn't have it. I guess the word "bright" has different meaning to different people - or there's something wrong with your tweeters. That's improbably though since you've built more than one speaker and they presumably sound the same.

    What speakers have you heard that do sound bright?
  • 01-04-2005, 04:30 PM
    knac67
    re-phrase of question.
    Thank you for the replys everybody. I am busy doing a re-model and have not had a chance to take apart the speakers yet. I used the word bright which may have not been the correct term i was looking to use. I would like the speakers to be slightly more forward or crisp in the high end. I am comparing these speakers to a pair of ascend cmt 340's
    which have a very detailed high end. I am looking for something that has a sound in the middle Of the ar.coms and the ascends.
    I am juist on about hour ten on breaking them in I don't know if I should wait longer before adjustments. I have noticed a huge imprvement in the bass since the break-in so far. If anyone has experience with extened ownership--please let me know..
    Thanks Again!!


    One last note..Thank you Ed Frias for the design of these speakers-I like them more each day!
  • 01-05-2005, 12:22 AM
    EFE Speakers
    AR.com DIY Crossover Adjustment
    Knac67,
    I designed the DIY crossover with the option of adjusting the detail just as you are requesting. Unfortunately, Madisound is not sending out the crossovers to customers with this option.

    The design shows a 5 ohm resistor mounted on the circuit board and a number of optional resistors to choose from (1 to 6 ohms) to be installed at the tweeters positive terminal (where it would be easy to remove and change). I recommend installing a 2 ohm at the tweeter as the standard to start with, then you can lower the resistance to brighten the sound or raise the resistance to soften it. Usually lowering or raising the resistor value by 1ohm would satisfy just about anybody wanting to change the sound.

    I have recently discovered that Madisound is sending out the crossovers with a single 7 ohm resistor ( = 5 + 2 ohms) mounted on the circuit board. Although this is the standard amount of resistance I recommend, it does not allow the customer to lower the resistance (to add detail) without opening the speaker, removing the crossover and then changing the 7 ohm resistor to a lower value. The whole purpose of the extra resistor mounted at the tweeter was for convenience of adjusting the speaker without having to disassemble and remove the crossover. If you have a 7 ohm resistor on the board, remove and change it to a 5 ohm, then add a 1 ohm resistor at the tweeters positive terminal using male and female quickdisconnets (.110 inch) for ease of changing. If the 1 ohm is still not detailed enough, then remove the 1 ohm resistor all together and just go with the 5 ohm on the board, that should be more than enough detail (too bright for me).

    The positive wire going to the tweeter should be the same length as the negative, but when you install the resistor in-line, you'll need to fold the positive wire enough to make up for the extra length the resistor adds. If you end up using no resistor in-line, then simply unfold the wire (female QD at the end) and hook it directly to the tweeter.

    If you would like to e-mail me directly, I'll be happy to e-mail you a comparitive audition (AR.com vs. GR Research) I posted last year using different resistors. Thanks!

    Ed Frias
    EFE TECHNOLOGY Speakers
    efespeakers@commspeed.net
  • 01-06-2005, 08:43 AM
    kexodusc
    Hi Ed,

    Geez, I just ordered 3 more pairs to complete our home theaters...had I known this I would have assembled the crossovers myself? Oh well, it's not like resistors are expensive, not sure what I can use six 7 ohm resistors for...maybe I can fetch a good buck for them on ebay? :)

    I didn't bother adding the resistor yet, as I feel they sound great as is, but it'd be fun to experiment. I'm assuming I have the 7 ohm x-o's..

    As we tweak the high detail of the Ar.com DIY's with this resistor, is there anything similar we can do to the modified BIC DV-62CLRS's? Or should we even bother?

    Finally, was the 7 ohm standard resistance chosen because of your preferences, intentionally selected to sound similar to other speakers...what's the story there, and what's your preference?
  • 01-06-2005, 08:56 AM
    kexodusc
    kcac67...I've only ever heard the Ascend CBM-170's, which are good in their own right, but are nowhere near the performance of the ar.com DIY's for the same price...how would you say they DIY's sound compared to the CBM-340 for those of us who haven't had a chance to hear them?
  • 01-06-2005, 06:54 PM
    EFE Speakers
    AR.com DIY Detail Adjustment
    Ken,
    The 7 ohms of resistance is the correct (total) value for the best all around sound from the DIY's. As I've stated many times, what sounds best in various systems will depend on the overall equipment being used. Example: Using a tube amp will probably soften (warm) the sound a little and using a 1 ohm resistor or no resistor at all at the tweeter may sound better. Using a receiver usually makes the sound a little brighter and may require a 3 or 4 ohm resistor at the tweeter.

    After designing the latest version crossover for the DIY, I spent many hours comparing a number of very good recordings using various value resistors at the tweeter, the 2 ohm sounded best with the ATI amps that I use. When I switched and used one of the 100wpc Sherwood receivers that I sell with the modified BIC speakers, I found I needed to step up to a 3 or 4 ohm resistor at the tweeter. It's not because the receiver is really brighter, but like most receivers it didn't produce as good a bass as the ATI amp, so whenever you lose bass or highs the "balance" of the sound changes causing the sound to sway towards the opposite end. Less bass causes the highs to be more prevalent, less highs causes the bass to be more prevalent. If one were to change the 5 ohm resistor on circuit board of the DIY to say 3 or 2 ohms, the speakers will take on an entirely different sound, it will become too bright and will sound like it lacks bass, even though you never made any adjustments to the lower frequencies. Balance is a critical issue with speakers and can make one either hate or love them, figuring that everything else is correct.

    I used to modify speakers for customers on a regular bases before I marketed EFE speakers. I remember a pair of Boston Acoustic towers a customer brought over for me to audition, they were bright, harsh and in my opinion very out of balance. He stated if there was nothing I could do to make them sound better, he'd buy a pair of my speakers. After several steps of toning down the tweeter, the speaker took on a completely different sound, the midrange came alive and the bass was better. Needless to say the customer was absolutely blown away and felt he had a brand new pair of speakers. Of course I lost a sell but made the customer very happy! Hope that helps? Thanks!

    Ed Frias
    EFE TECHNOLOGY Speakers
  • 01-12-2005, 04:04 PM
    dave_bullet
    Thought I'd join in here.....

    After listening to the AR.com DIYs for a few months the music coming out of them (I worded that intentionally) is too bright for me. I'm using a Marantz SR-6300 with an older Denon CD player (all analog hookups) - source direct on the amp. Changing source to a DVD player and using digital out with the SR-6300 added a little more detail but the speakers still sound too forward to me. Let me explain what I don't like, as I am going to pad the tweeter down a bit to see if it helps
    - male voices are sibilant ("s" sounds overly pronounced)
    - male voices lake "weight"
    - brass instruments drown out the rest of the music
    - about 2 octaves of bass seems missing / light (I'm guessing approx 200Hz to 800Hz). This could be because the treble is drowning it out
    - the fabric dome tweeter seems to not have as much "air" as the metal dome in my previous pair

    I find if I go -4dB on the amp (10KHz treble) it helps sibilance but does dull the detail. The speaker still sounds forward - so I'm guessing it is something in the 4KHz - 8KHz range.

    I'm not necessarily blaming the speakers, but they are easier to modify than other components at a lot less cost. It could be a combination of:
    - Bright amplificatin (Marantz receiver). I've been told most receivers do not exercise the bass authority of a dedicated / quality power amp.
    - too much dacron on the back wall (dampening the bass)
    - reflective surfaces in room (mine is fully carpeted with no hard walls / windows next to the speakers). Placement, drawing blinds makes negligble difference and large changes here are impractical anyway
    - the natural cone breakup of the woofers around 4KHz not being tamed enough?
    -... or I just like my treble padded down a bit.

    I have the madisound pre-built xover with the 5 ohm / 2 ohm combo. I have 2 ohm resistors so thought I'd try that, and if too much go to 1 ohm.

    I was also thinking of removing some more dacron / replacing with the Madisound supplied foam as MCH I think did.

    Cheers,
    David.
  • 01-12-2005, 05:51 PM
    EFE Speakers
    Tone down the DIY
    Hi Dave,
    Most of the problems builders have encountered with lack of bass was because they installed too much insulation or installed the wrong kind. 2 to 3 inches of very loose polyfill on the back wall of the cabinet is all I recommend, the speaker wire usually holds it in when set upright. Take one medium handfull of loose fill and spread it around the back wall while the speaker is laying on its back.

    To tone down the DIY you'll probably need to add a 3 to 5 ohm resistor at the tweeter, not a 1 ohm which will make it brighter. By adding just the right amount of resistance, you'll find the sibilance gone and still produce good detail. Reducing the sibilance will cause the midrange to sound a little fuller because the balance will change from the top end to the mid and lower range.

    You are correct regarding receivers, they DO NOT produce bass like a good power amp. Several of my customers that have recently bought Pioneer Elite receivers and have complained about the extreme brightness, not only with my modified BIC speakers but with my EFE line as well. I'm sure your lack of bass is because of too much insulation, but you might want to try your speakers on another system with a good amp just to see how they sound as is. Success and let us know how it goes. Thanks!

    Ed Frias
    EFE TECHNOLOGY Speakers
  • 01-12-2005, 05:54 PM
    Rob H
    AR.coms bright?
    Dave,

    I originally was powering my AR.coms with a Denon DRA-685 receiver. Certain cd's did come across as too bright with the Denon. And, I, too, experienced a lack of bass. The problem was not the AR.coms, but was with the Denon. I recently upgraded (actually price wise a down grade) to a Panasonic XR25 digital receiver. I have posted the results of this match up on this same forum.Sound is now completely balanced with detailed (yet not bright) highs and much better bass. I am more than pleased with the AR.coms when paired with the Panny.
    At $199 for the Panasonic, it is a remarkable deal. BTW, as I mention in my other post, I have changed the dampening in the AR.coms quite a bit to get the sound that works for me.

    Rob
  • 01-12-2005, 06:09 PM
    kexodusc
    I'll definitely echo Ed and Rob's sentiments. I have a relatively beefy receiver (Yamaha RX-V1400) but even it sounds a bit thin, tiny, dull in the midrange and lacking in the bass when compared to even an inexpensive power amp like my AudioSource Amp/One. On my Rotel and Adcoms the difference is quite noticeable.
    That is, in my opinion, a consequence of a detailed, accurate speaker, they can reveal flaws in the rest of your equipment.

    That being said, personal preferences and hearing abilities could mean you just like less treble.
    I'd advise against the Madisound foam, when I rough demoed that stuff, I found it over-dampened things, and the speaker lost a lot of the natural attack/decay response on strings, and symbals...subtle, but annoying. I think the foam is just standard stuff in all madisound kits though.

    Dave, do you have the speakers toed-in or are they firing forward? I find these require VERY little toe in relative to my Wharfedales and Paradigms, which always required quite a bit.
  • 01-12-2005, 06:21 PM
    Rob H
    Interesting comment re: the foam pads from Madisound. I tried them early on with the Denon and didn't like the sound. I am now currently using them, along with a piece of Acousta Stuf behind the woofer. One would think that this is too much dampening, but the combination sounds great in my system.

    Rob
  • 01-12-2005, 07:51 PM
    dave_bullet
    Hi there,

    I've tried various placements (distance from back wall, toe-in in vs straight on, close vs. far apart) and the sound doesn't really change.

    I'd like to borrow a proper integrated or pre-power amp combo to see if that does change things. Based on your advice it probably would, but that would be a long term option for me.

    I've got a 70's pioneer receiver so will do some A/Bs (as best I can) with the Marantz to see if that makes a difference.

    I did notice the Marantz is more mellow than the Denon I had.

    All I want is a really mellow / laid back sound - with heaps of toe tapping detail - is that too hard? :-)

    Thanks for your advice

    PS: I will also double check the xover hookup to make sure I have it all correct. The drivers are supposed to be wired in phase - correct?

    Also - how much power can the AR.com DIYs comfortably handle. Yes - I know you can hook any amp up to any pair of speakers (impedance to be noted of course) but what power rating, what class (A, AB etc...) would people recommend?

    Cheers,
    David.
  • 01-14-2005, 12:10 AM
    dave_bullet
    Thanks for the advice Ed - I actually skipped over your reply by mistake.

    I'll remove a little fill as I think I've overdone it. I'll see if I can borrow a good power amp too before modding the speakers.

    I'd really like to buy this little beasty... (500w/ch Perreaux)

    http://www.trademe.co.nz/structure/a...sp?id=20704173

    Dave.