Olaf Posted June 11, 2001 Share Posted June 11, 2001 I know the damping factor of the amp controls the amount of speaker vibration once the signal ends. How audible is it and what would the lowest acceptable measurement be? Is 60 at 8 ohms decent? Quote Link to comment Share on other sites More sharing options...
jeffgeorge Posted June 11, 2001 Share Posted June 11, 2001 Oalaf, I must say that it is refreshing to hear somone talk about damping factor. Although I don't believe my receiver has a really good one, some of the best amps have 200 and more. In a receiver, I think you are well off to have 60 - 150. There may be some that offer more, but I don't know which ones they would be. I must confess that several years ago I used to sell hi-fi equipment -- Yamaha included, and with some speakers the Yammies sounded pretty good, but with Klipsch, quite harsh at times. Even though Yamaha usually sports some pretty good specs, that does'nt mean they will sound good in your home with Klipsch. ------------------ RF-3's : mains RC-3 : center RS-3's : surrounds KSW-12: subwoofer Receiver: Denon 2801 DVD: Panasonic DVD-A120 CD: Yamaha CDC-765 Cables: Tributaries Sat Receiver: Hughes Direct-TV DD5.1 Quote Link to comment Share on other sites More sharing options...
stormin Posted June 11, 2001 Share Posted June 11, 2001 dont really think damping factor makes much of a difference my little old adcom 555 mkII has a >800 and doubt that you could hear the difference between yours at >60 Quote Link to comment Share on other sites More sharing options...
roy Posted June 11, 2001 Share Posted June 11, 2001 a high damping factor is thought to give the amp more control of cone movement and thus provide a tighter cleaner bass in particular....i too am not sure about this in reality as even i too have a parasound amp that delivers greater than 800 for damping factor..although it does seem to give a slightly warmr and tighter bass i wonder how much of this is pshycosomatic (in other words in my mind)and how much is reality! another dubious spec is slew ratio showing how fast an amp can go peak to peak with voltage from the power supply but thats another one that alot of experts cannot agree on the actual difference it makes on what we hear....oh well ------------------ my equipment: klipsch rf-3 (main) klipsch center ch speaker boston acoustics (rear) mirage ss-1500 subwoofer yamaha 795 receiver driving center and rears parasound hca-1500 amp driving rf-3s mirage subwoofer 1500 watts! sony 650 dvd/cd player sony minidisc/cd player combo panasonic hifi vcr waiting to see what new reference line will sound like in 2001!! Quote Link to comment Share on other sites More sharing options...
Mighty Favog Posted June 11, 2001 Share Posted June 11, 2001 The Rotel RB-1080 amp I recently bought has a dampening factor of (get this) 1000. Funny, the only things I was really looking at was THD (.03% max at half rated power) and s/n ratio (116db to 120db depending on where you look). I must admit that I too had no idea what the dampening factor was but it's good to know I can grin when mine (or just place your name here) turns out to be a good one. ------------------ Tom KLF-20 Mahogany Carver C-1 (McIntosh C33 is coming!!) Rotel RB-1080 Yamaha PF-800 Turntable/ Sure V15 Type V Cartridge Ortofon VMS-30 Cartridge Stanton 999SS Cartridge Carver TL-3100 CD Yamaha K-1020 Cassette (maybe being mothballed) dbx 1231 EQ H.H. Scott 830z Analyzer Monster Interlink 400mk II Monster Interlink 300 mk II Studio Tech U-48RW Cabinet Original 12ga. Monster Cable This message has been edited by tblasing on 06-11-2001 at 11:47 PM Quote Link to comment Share on other sites More sharing options...
Ray Garrison Posted June 12, 2001 Share Posted June 12, 2001 Damping factor and output impedence are two different ways of looking at the same thing, FAPP. Aside from the ability of the amplifier to control the motion of the woofer, damping factor will give you an idea of how the amp will interact with a speaker that has a widely varying input impedence. An amp with a very high damping factor, indicating a very low output impedence, will not exhibit significant alterations in its frequency response no matter how much the speaker's input impedence varies with frequency. It'll sound about the same with any speaker. An amp with a very low damping factor, on the other hand, will tend to interact with a speaker's impedence, and if a speaker's impedence tends to wander all over the place as the frequency varies, then the amp is going to sound quite different into this speaker than it would into a speaker with a more linear impedence. Ray ------------------ Music is art Audio is engineering Quote Link to comment Share on other sites More sharing options...
Tom Adams Posted June 12, 2001 Share Posted June 12, 2001 There are obviously more folks here that can speak to the technical side of dampening factors than I, however, I feel it's an important spec to look for that gives an insight into the build quality & design of the amp. Back in college, my Heresy's were hooked up to a friends Crown DC300A from time-to-time (frat parties typically required confiscation of stereo gear) and it was amazing how tight the bass was. The Crown had a dampening factor of >1000:1. Equally amazing was how one could hardly see the woofer cone move, yet the bass was pounding you in the chest. OTOH, when my speakers were hooked-up to another guys' Kenwood, the bass was muddy and the woofer cone quivered to the point of me being scared to watch it. Before my Denon 3300, my Heresy's endured being driven by a Sony reciever and the Sony would make the woofer quiver at elevated volumes. However, it is much less pronounced with my Denon and, once again, the bass is much tighter with the Denon than the Sony. When I got started into the wonderful world of audio, my mentors pointed out dampening factors as being a good thing to look for in a quality amp. And I believe that to be true. Tom Adams Quote Link to comment Share on other sites More sharing options...
discorules Posted June 12, 2001 Share Posted June 12, 2001 Here's my understanding of damping factor. Like the others have stated, higher damping factors generally mean that the amp will have tighter control on the motion of the woofer. There can be too much of a good thing however. Higher factors are generally associated with high orders of negative feedback. When this is the case, the transient response of the amplifier worsens. As with many things in life, moderation is the key. The Heritage line of speakers should not require a high damping factor because the woofer cone motion is relatively small due to horn coupling. Another reason why I truly love the Heritage line, esp. the KHorns. Woofers that are long throw and therefore have higher excursions will require a higher damping factor to control their cone motion. Quote Link to comment Share on other sites More sharing options...
Olaf Posted June 12, 2001 Author Share Posted June 12, 2001 Gentlemen... Thanks alot for the input! :-) The reason I asked is because I thinking about buying a new Onkyo no. 8511 reciever. Since my Yamaha RX596 sounds absolutely horrible(jeff George is 100% correct) with my new RF-3's,I switched to my 21 year old onkyo TX3000 and it sounds 1000 times better than the Yamaha. It's old has has a minor problems but is still functional. The Yamaha damping factor is 200 but it still sounds like garbage with the mids and highs. My old Onkyo has a 40 factor and the bass is tight and punchy and the 8511 has a 60 factor. So,I guess that's a decent number and anything higher could possibly be inaudible anyway. So,if Onkyo still 'makes 'em like they used to' and they still have the warm and ambient sound I will buy one ASAP. Quote Link to comment Share on other sites More sharing options...
WMcD Posted June 12, 2001 Share Posted June 12, 2001 Ray, pardon my ignorance, which is boundless. FAPP? Gil Quote Link to comment Share on other sites More sharing options...
JJT Posted June 12, 2001 Share Posted June 12, 2001 FAPP= For all pratical purposes? I think. Joe T Quote Link to comment Share on other sites More sharing options...
Audio Flynn Posted June 12, 2001 Share Posted June 12, 2001 Nothing better than getting Ray and Gil to comment on the same thread. I have used Dennon, Marantz, Yahmaha and Kenwood overe the past 25 years for amplification; Due to damping factor and other considerations I would like to try NAD for my next amp. I cannot afford really expensive SS stuff or tubes. Quote Link to comment Share on other sites More sharing options...
PhilH Posted June 13, 2001 Share Posted June 13, 2001 Olaf: After reading reviews and specs on the limited number of stereo "basic" receivers out there today...I picked up an 8511 to go with my new RB-5's. I'm very impressed with the performance of the system, especially in a non auoustic-friendly room with the RB-5's high up on shelves on either side of the fireplace. Bass seems tight and deep and everything sits on the "flat" setting. PhilH Quote Link to comment Share on other sites More sharing options...
Ray Garrison Posted June 13, 2001 Share Posted June 13, 2001 Joe T, Gil... yep. FAPP = for all practical purposes. Sorry bout that. ------------------ Music is art Audio is engineering Quote Link to comment Share on other sites More sharing options...
Klipschguy Posted June 13, 2001 Share Posted June 13, 2001 Olaf, That's strange your RX-596 sounds bad. There must be speaker preferences for equipment. My Yamaha RX-596 (FYI, mine has a rated damping factor of 240+) sounds outstanding with my Cornwalls. My old Carver sounded so harsh and bad that I gave it away. For a while I was also using a push-pull tube amplifier with my Cornwalls that sounded quite good indeed, but could not match the deep, controlled bass and smooth mids and highs of the Yamaha. You put on a Diana Krall CD with my system, give it a couple watts, close your eyes, and you'll be tranported to a secluded piano bar with a beautiful band playing - musical all the way. Anyway, if the Onkyo sounds best with your speakers, by all means stick with it. Same for you Carver fans out there. Klipschguy Quote Link to comment Share on other sites More sharing options...
WMcD Posted June 13, 2001 Share Posted June 13, 2001 My read is that once you get a damping factor higher than the single digits, it should not make a big difference. A damping factor of 60 at 8 ohms indicates the internal impedance of the output of the amp is 8/60 ohms. That is a pretty small number. 0.13 ohms. It is getting close to a dead short. A damping factor of 600 would indicate 0.013 ohms. Granted a better short circuit. But what is the big issue? It is that we may (see infra) want to have some mechanical resistance to keep the excursion of the diaphragm controlled at resonance. Where does that mechanical resistance come from? We usually think of the driver as a type of elecrical motor. We put in a signal and the magnet and voice coil are a motor to drive the diaphragm back and forth. But the magnet and voice coil can also act as a generator. If the diaphragm has mass and is oscillating, the system creates current. The current flows into the output stage of the amp. We assume the impedance of the amp is quite close to a dead short and thus it is hard for the diaphragm to crank our generator and load. That is the mechanical resistance created. This seems well and good, but what actually is limiting the amount of current the generator can create? Answer: It is not only the internal impedance of the amp; rather we have to consider all the resistance in the loop. A big factor is the voice coil resistance itself. Let's assume it is 8.0 ohms. Taking that into account, the resistance in the loop overall, given our two examples, is 8.13 ohms and 8.013 ohms. (Resistances add in series.) Thus in practice that is practically no change. Of course a damping factor of 1 would indicate an internal impedance of 8 ohms. Now the total resistance is 16 ohms. So this could adversly lower the current and the speaker diaphragm would be more free to oscillate. You can see the math. If there is damping factor of 10, we have 8.8 ohms in the loop. This is just 10 percent away from the effect of a perfect short which would cause 8.0 ohms. In some ways, it is good for us that the speaker voice coil resistance is the dominating factor, and that changes in the "damping factor" are a minor factor, once you get up to higher numbers, as shown above. In the design of the speaker / box combination, the amount of resonance is an important factor in creating bass response. In fact, "over damped" drivers have poor bass response. We want the electrical resistance in the loop to be predicatable from amp to amp. This is related to the Qts of the speaker which has a major factor in T-S design parameters. I can't explain why Tom saw no excursion with one amp and a lot with another. Maybe the second one did have a very small damping factor. Also possible is that the program had different bass notes. If you feed the acoustic reflex speaker with a note at its resonance frequency, it should move quite a bit. That's what I think. But my knowledge is imperfect. Gil This message has been edited by William F. Gil McDermott on 06-13-2001 at 08:29 PM Quote Link to comment Share on other sites More sharing options...
mace Posted June 13, 2001 Share Posted June 13, 2001 Audio Flynn: I've got a 10 year old NAD 3240 integrated amp(40 W RMS, 200 W peak into 4 ohms, no receiver) driving my KLF 30's. Many moons ago I drove some cornwall I's (1982 vintage) with the NAD. I've always been happy with this amps performance and clean, dynamic sound. I'm not sure about the newer NAD's but the old ones used to use power envelope technology which allowed a lot of dynamic headroom (up to 6 dB) which made for a lot of amp for the money. As far as pure musicality there are better amps but you're going to pay a *lot* more for them (smoother, more tempered sounding amps). NAD reminds me of Klipsch's philosophy.. for the money (while not totally cheap) the performance is just amazing, especially for hard driving rock music. I find the NAD/Klipsch combo is even better than going to a concert (don't get beer spilled all over you and crushed by the crowd!) FWIW the damping factor on my NAD is listed as ">50 (8 ohms)". I've always found the bass effortlessly punchy and full, if that makes any sense. I'd definitely seriously consider NAD again if I was on the market for a new amp (which I may be soon, for a power amp). Mace Quote Link to comment Share on other sites More sharing options...
boa12 Posted June 13, 2001 Share Posted June 13, 2001 i'd be glad to know what the damping fact of my marantz sr-8000 is. getting info from them is quite difficult ------------------ Klipsch KLF 30 (front), KLF C-7, Cornwall I (rear) Velodyne HGS-18 sub woofer Monsterbass 400 sub interconnects & Monster CX-2 biwire & Z-12 cable Marantz SR-8000 receiver Sony DVP-C650D cd/dvd player Sony Trinitron 27" stereo tv Toshiba hi-fi stereo vcr Technics dual cassette deck Scientific Atlanta Explorer 2000 digital cable box Boa's Listenin Lounge: Klipsch RF-3 (front), RC-3, cheap little Technics (rear) Monster MCX Biwires Sony STR-DE935 a/v receiver Kenwood KR-9600 AM/FM stereo receiver (vintage 1975) Russound AB-2 receiver switch to RF-3 Teac PD-D1200 5-disk cd changer Technics SL-1950 turntable/AT LS500 cartridge Sega Genesis game player Sub: None yet rock on! Quote Link to comment Share on other sites More sharing options...
Olaf Posted June 14, 2001 Author Share Posted June 14, 2001 <i>That's strange your RX-596 sounds bad</i>. Klipschguy...That's what I don't understand. Back in the late '70's,I knew three people who had the Yamaha/Klipsch combo and they all sounded great. All three had the Yamaha 2040. Two had Cornwalls and 1 had LaScallas. Perhaps I got a lemon because I had it for a month and a channel blew out on it. Speaking of LaScalas...In one of my old bands(approx. '77) we used LaSallas for our PA. system. Between gigs our bass player would use them in his van wired to a 4 watt per channel Pioneer Supertuner. It pushed those Lascallas with no problems. PhilH Thanks for the info on the 8511. I'm very seriously considering a purchase of one very soon. If it's anything like my old unit,I know I'll be more than satisfied with it. Incredible knowledge on this board!!!! :-) Quote Link to comment Share on other sites More sharing options...
boa12 Posted June 14, 2001 Share Posted June 14, 2001 ahhh the pioneer supertuner. another 1 i hadn't heard for a while. yeaa those (back) seat memories (mamories). Quote Link to comment Share on other sites More sharing options...
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