I am convinced that there is more to the Class D amp sound I hear with the OHMs than power and current alone accounts for.
There is a tube amp-like aspect to the amps ability to go loud without causing fatigue or overall brightness. I have read (in an article published by a gentleman from SPectron) where this might be due to unique negative feedback design advantages with switching amps that can help keep the timing delay when applying NF minimal compared to other amp designs. Its consistent with what Ralph from Atmasphere regularly cites as an advantage of no NF amps. Or in the case of switching amps, ability to apply negative feedback more efficiently. I do not understand the technical details of how this works, but what I have read there and similar accounts from other reputable sources tells me that this might be a unique positive attribute of CLass D amps.
ALso, latest generation Class D amps appear to be pushing the bar significantly higher still in terms of switching frequency possible, which enables better low pass filtering needed with switching amps and on paper at least would seem to raise the bar in terms of technical capabilities of Class D. Can things get even better? I suspect so, though CLass D amps already seem to bring a lot of unique benefit to the table IMHO. |
Thanks Bondmanp,Mapman.
What about those crown xls amp? Anybody use this before with ohms? I read that they getting better as well and cheaper too.
I can pickup a used parasound hca 1500 for $400 today but now i am having second thoughts...i might have to just save a bit more for the class Ds.
Got additional info on the sw2.2k regarding the bass settings. Apparently for those who dont have the external controls (micro,1k,2k,3k,4k) there is a way to tweak the bass on the ohms if you find it too boomy or not enough. You can remove the cup where the speakers are connected to and there is a switch to adjust the bass. By default it is set to middle. I adjusted mine after telling John that i was having too much bass with the ohms and he instructed me to do this.
It is a hidden setting so that you can adjust the dynamics if you ever move it to a different room in the future. Turns out that the issue with mine was due to the dynamic audessey setting where i need to adjust it to 15db so i moved it back to the mid seting. |
I'm reading Crown XLS amp IS Class D. Don't know much more about them though. Might be a good value + worth a try. Crown is mostly used for pro audio applications these days but home audio use should be possible. They use older Crown amps at my gym for classes + such. |
I have a question for the inveterate amp swappers out there. What effect, if any, does a higher damping factor have on Ohm Walsh performance?
Rather than opt for massive power increases, could one get the same/similar (or different) improvements in the drivers' sound quality through an amp with more damping? Alternatively, is higher power somehow the functional equivalent of a higher damping factor?
I've got a vintage Sansui with 90 (honest, conservatively rated) wpc, and a damping factor of 100. I'm thinking of using it as a pre-amp and running it into a NAD power amp with 125 (also honest) wpc but a damping factor of > 200. I'm not sure the difference in watts would make that much difference, and the Sansui is a much, much faster amp. I'd like to hear some opinions as to whether it would be worthwhile before I lug that NAD beast upstairs and hook it up. |
JWC,
Higher damping and higher power are two different beasts, though the two might go hand in hand practically in many cases.
My experience with the larger OHM 5s is that they benefit from both high damping and high power and high current as well. All may often go hand in hand practically with most amps.
Damping is needed to keep dynamic drivers under control to various extents. Some drivers are more highly damped already. Walsh drivers in particular seem to loosen up over time more so than most and benefit highly from higher amplifier damping factors. The vertical mount of a Walsh driver and the increased effects of gravity accordingly might have something to do with this.
In practice, effectiveness of amp damping factors >50 or so is questionable. However, I have found with teh larger OHMs, where low end bass levels are seldom an issue, that more damping is always a good thing in terms of lower distortion and better dynamics and speed in general, ie a lean and mean bass as opposed to a fatter less refined delivery. The amps I prefer with my larger OHM 5s have 1000 damping factor. I have used other amps with 50 or less damping factor (also less power) and can hear the difference even at modest volumes.
Smaller OHM drivers benefit somewhat less from massive power and damping than larger models, but these things are still of benefit I would say, at least up to the point where a combo of high damping and smaller driver negatively affects bass levels, though I am not sure I have experienced that myself practically, even with my smaller OHM 100 driver based speakers. I would say that with the smaller drivers, cases where users prefer less damping in the amp might become more common, depending on preference, room acoustics, and other factors. |
ALso I should note that the benefits of higher damping with the OHMs may be most apparent with the bass, but higher frquencies including all frequencies up to 7Khz or so handled by the vertically mounted Walsh driver part of the OHM CLS benefit with lower distortion and greater articulation and rendering of detail as well I would say. |
So i did buy the parasound amp and all i can say is now i understand why more power sounds even better with the ohms. The music just sounds so effortless and the bass from this 2000 driver sounds amazing that i turn off my subwoofer.
The mosfet design of the amp somehow smoothens the highs but you dont get fatigue out of it. On the other hand the niles amp sounds more forward and i feel that there is more of a realism like the raspiness and chestiness of the voice. Overall i prefer the mosfet sound better as i can listen to it all day. |
Drake.
THere ya' go!
Enjoy!!! |
I looked at my Bryston 14BSST specs and it has a damping of 300. Now it has 600 watts but wondering if im getting optimum results driving the Walsh 5000's. Mapman, what difference exactly did you notice going up to an amp with a damping of 1000? |
BlueR,
Theoretically, there is probably little if any practical sonic difference attributable between damping of 300 versus 1000. The consensus seems to be that most speaker wire electrical properties alone negate any differences once damping passes 50 or so. I moved from Carver amp <50 damping to Musical Fidelity at around 50 to current Bel Canto with damping 1000. The Bel Cantos seem to have the most controlled, dimensional and articulate sound top to bottom of any of these with the OHMs by a wide margin. There are many factors that might account for how a Class D switching amp performs versus conventional Class A or A/B. In a nutshell, the 500 w/ch Bel Canto ref1000m amps drive my large Walsh 5 effortlessly and without breaking a sweat at any volume I have attempted. They retain mostly the same sound quality at any volume, however as the volume goes up teh music becomes more full bodied, dynamic and lifelike, like blowing up a balloon. Never any sign of strain, clipping or noticeable distortion at any volume. Things just keep expanding and becoming more full bodied and lifelike as the volume goes up. Midrange is very clean and articulate. Vocals are lifelike and lyrics clearly understandable with most any decent or better quality recording. |
Thanks for the response Map.
I recall reading that John Portis at Stereophile was a big Ohm fan and adopted an Electron Kinetics amp as his reference piece, in part because (if I remember correctly) of its high current and damping that matched well with Ohm Walshes. My Sansui is supposed to deliver plenty of current, but doesn't deliver high damping specs--hence my question.
As you suggest, there are so many other factors that distinguish amplifier performance with a given set of speakers that we'll likely never conclusively settle the matter.
I know that the whole damping debate continues, and that it theoretically shouldn't matter above 100 (that's the figure I've always come across), but I'm in no position to adjudicate the claims pro and con. I don't even claim to understand the physics/electronics theory underlying the arguments about damping.
If/when I hook up the NAD and/or Adcom, I'll let you know if I hear any differences. (Bel Canto 1000 wpc amps will likely have to wait for another lifetime.)
This really is an extraordinary thread. It's turned into an Ohm's-eye view of all things audiophilic. What does this say about Ohm speakers--and about Ohm-heads? |
Jwc,
the late john Potis, who ironically I found out lived right down the street from me, was a long time OHM fan. I asked him about amps for my newer OHMs a few years back via email and he responded at the time encouraging me to throw the kitchen sink at them amp-wise, including damping. He was one reviewer whose opinions and insights I learned to always take to heart! |
John was a great reviewer with a lot of respect. It was his review about the MicroWalsh Talls that convinced me to give them a try. His viewpoint is missed in the community. |
Just scored a circa 91 Denon DRA-545r stereo receiver for $20 at Goodwill and man I can't believe that it bested the zpre2+niles si245 separates. It even sounds better than my main system which is the marantz avr+b&k amp. I was just testing it using pandora in kindle fire and compared it to the three setup and it bested them both (using the ohms as the speaker). It just sounded so airy and holographic and to think that it was just a 64kbps pandora stream.
This leads me to believe that the newer avr with all the bells and whistles crammed into it are not up to par with the sound quality of the old when it comes to 2 channel music. I think I'm going to use this as my preamp along with the parasound amp as my main 2 channel system. |
IF a newer amp has lots of bells and whistles and sells for a price comparable to comparable powered gear with less b+ws sold 20 years ago, I'd say there is a fairly good chance the older unit can outperform the newer since the newer unit does more things and cost does not reflect the impact of inflation on a design from 20 years ago. |
I noticed during spinning class at a brand new gym yesterday that the newer Crown Class D amps were being used with Peavey (horn) speakers there. Sound was very good, much clearer and dynamic than older non Class D Crown amps in similar setup at my older gym. Amps are more commercial looking in design being for professional use mainly but I think they could do quite well in a home application for very reasonable cost. |
Disclaimer: OHMs and Peavey commercial horns are opposite ends of the spectrum in terms of design, but I still would be interested to hear how the Crowns might do with OHMs. From what I read they use some Harmon International proprietary Class D chip circuitry that may or may not be up to the task of driving a less efficient and more difficult load than most pro speakers present. |
I just got through making a cradle around my OHM 5000's. Let me explain. I have them sitting on 15" X 15" granite slabs and 4 tip toes underneath. Even with the wheels locked they were a hazard of falling off. I have better bass response under the granite. I took a 1 X 6, stained them same shade as speakers and used L brackets to connect. Looks pretty cool. I will post pic later on my page. Has anyone placed granite underneath their OHMs and could they tell a difference? |
Odd note of the day:
After a ton of experimentation with room position, my Ohms ended up sitting atop a pair of subwoofers. The added height seemed to improve imaging and the subs (plus Audyssey) made any impact on the bass output irrelevant. Of course, this decision led to a ton more experimentation: What goes between the top of the subs and the bottom of the Ohms?
I tried tile, marble slabs, wood shelves, with hard cones, soft rubber footers, etc. I ended up using one tick towel per side. It doesn't make a ton of sense, but it seems to damp the vibration from the sub while also keeping the speakers stable.
I understand that this one flies in the face of audiophile dogma, but it worked better than anything else I tried and better than traditional on floor placement.
Go figure.
Marty |
On my Ohm Walsh 3's I removed the casters and replaced them with solid rubber footers. Then, because they sit on carpet I went down to Lowes and picked up a piece of solid birch 1" thick which I cut into two 14" squares, after painting them black I installed 1 1/2 spikes.
I placed the new stands where the speakers were previously positioned and put the speakers with their new footers on top (leaving about an inch of clearance). To me the bass sounded noticeably cleaner and more defined, not a night and day difference but better nonetheless. Plus they look a little better to boot. |
I have been using a pair of Ohm 200 MKIIs in my system for about 12 years. I have made regular upgrades to the system based on my impression of the "weak link in the chain". After each change the Ohms have been fully capable of revealing the improvement in system performance. My last upgrade was the addition of a very high end Thor preamp which made a dramatic improvement. I will be traveling to Montreal this week to retrieve a pair of Classe DR3-VHC super high current monoblocks that I had recapped and have never used. These amps were desinged to drive Apogee Scintillas. I fully expect another huge improvement in system performance. The point of this is that whatever changes I have made, the Ohms have responded and I have never considered them the weakest link. Pretty remarkable for a pair of $2000 speakers. I will probably be considering a driver update, but definitely not replacement. |
My 5000s sit on a suspended hardwood floor. I firmed up the bass considerably by installing 3 FIM pucks shown here:
https://www.gcaudio.com/cgi-bin/store/showProduct.cgi?id=325
under each speaker. No other modifications were made or added. Gets rid of vibration and resonance. |
I just blew the tweeters on one of my 5000 speakers. Is there a fuse to replace? or do they have to go back to factory. |
Blueranger, What did you do to make them "blow". What are the symptoms - just no sound? Was there any strange noise just before?
I would call John S. |
Right channel clipped on amp (600 watt Bryston) and high frequencies died on same speaker. I did not turn up volume anymore than usual. I never run in clipping. I always turn volume back. I sent John S an email |
I was using new balanced interconnects and that made volume louder and punchier. I did not have to turn volume control as high to get prior volume levels |
Sounds like you did nothing wrong. Dome tweeters are mechanically fragile instruments. |
Just though that I would jump in on this long running forum.. I am a long standing owner of Ohms starting back in the early 1970 with a pair of Ohm Fs, Currently using Ohms as my home theater setup with a pair of 300 MK11 as the fronts a 1000 as a center, walsh 4's(rebuilt) as surrounds and micro's as back surrounds... I am powering the 300MK11 WITH A D-SONIC 600/channel D class amp and the remaining 5 channels with a aragon multichannel 200/channel amp, 2 subs and a onkyo 5508 with sig upgrades by the upgrade co. This is the final result of many different attempts to produce the best home theater sound room (within budget) that I am able to. As Ohm fans we know how good they are for 2 channel but they are outstanding in a multi Ohm speaker home surround application Dennis |
Emailed John S and he said they are under warranty and I am sending both drivers (not cabinets) back for repair and matching. Just 4 screws to loosen then pick up. |
Holy schmoly!
Did I read that someone is considering a Crown XLS1500 to run a pair of Ohms? I use an XLS1500 professionally with my bass rig. I gotta tell you, I can run one channel into a 4-ohm cabinet and overpower a PA at an outdoor concert with that rig.
And actually, yes, it is a great amp for home speaker use- I know quite a few guys who do it. Although, with my Micro Walsh Talls it's overkill, so I don't.
There are two drawbacks that I am aware of. First, the noisefloor of these may may not be optimal. They're not exactly whisper quiet. Using the lowpass filter to cut some highs may be a good idea if you have too much high-frequency hiss.
Secondly, they want to see a high voltage at the input. They only have a 1.4 Vrms sensitivity, and experience and a lot of discussion has led me to want at least a 2 Vrms input, which I get with my Eden Navigator pre-amp.
If input sensitivity is an issue, then consider the Carvin HD2000. I also think it looks better, since it's black. |
Dsremer, I'm eyeing the D-Sonic 600 w/ch stereo Class D amp for purchase next year. In your opinion, have these new Class D modules surpassed Class A/B and are approaching pure Class A amp, sound wise. |
TObe,
I am interested in any review or comparisons you can offer on teh new D-Sonic amps as well. They use newer Class D amp technology and reviews and user feedback on them is in early stages. Thanks. |
Ditto. I too would like user feedback on D-Sonics as I will be upgrading shortly. |
In response to the question about d-class the d-sonics are quite nice and match my aragon 2007 multi channel in sonic bliss they really do a better job on the low end then many A/B amps that I have listened to. Now first I must let you know that the next d-class amps I am going to discuss I am now a dealer for...AVM MA 3.2 MONOBLOCKS these are in my opinion a sonic match for a number of very fine amps. I currently have been compairing these with my M Levinson 336 dual mono block... they grab the low end better have a wonderful mid and nearly equal the top end of my 336. Condidering that the 336 retailed for $10,000 12 yrs ago and the AVM MONO BLOCKS are a little over 1/2 the price run much cooler,and cost pennies to use, I feel these are a great buy. Also because of their much smaller size can fit nearly anywhere... I am becoming a big d-class fan. These are the 2 D-Class products that I have used enough to comment on, they are both non fatiguing, quick & powerfull easy to work with. I am very happy with both products....Dennis PrimeOne Media |
Which OEM provides the Class D modules for the AVM MA 3.2 MONOBLOCKS? |
Not to hijack this thread but here is your info regarding the AVM AUDIO MA3.2 MONOBLOCKS D-CLASS HYPEX BALANCED AND SINGLE END INPUTS BI-WIRE-SPEAKER TERMINALS 750-VA-TRANSFORMER WITH 50,000 uF FILTER CAPACITY 240W/CHANNEL 8ohms 430W/CHANNEL 4ohms totally stable at 3 ohms Please feel free to e-mail me at propofol@earthlink.net for more info Dennis |
Dsremer,
Other than cost, what are the biggest differences between m-sonic/Pascal Class D and AVM/Hypex Class D amps?
THanks. |
There is considerable more refinement( you really are not aware that you have exchanged a top A/B dual monoblock with d-class amps). With the AVM mono"s you can adjust the sonic signature with switches on the back... from clear to medium to smooth to match with different speakers, the bass controll is more defined,the bottom end will suprise you there is a clear sweetness to the mids with no glare produced, the upper end is not bright nor does it tend to roll off as some other amps will do. The d-sonic is used in my home theater with ohm 300 mk11 and it works well with the ohms, they sound faster in response more bottom end (requires a good power cord) The avm mono's is used in my main system with tyler woodmere's which are a more open top to bottom and can reproduce any weakness in the front end/amp used (also improves with a top power cord) I hope this helps.. both are very nice power amps but the avm's take it to the next level. p.s. any body need a M.LEVINSON 336 mine will be available soon Dennis |
Thanks Dsremer, for your first hand account and opinion. |
Just put my bryston o to my mwt's The prior posts re power are spot on. Bryston plus ohm equals beauty |
Kbuzz-
How's the bass response with the Bryston?
Last week I shut my sub off for headphone listening (speaker tap on my Marantz- just shut off the sub and I'm good to go), and forgot to turn it back on. It took a while to notice the sub was off when I went back to the MWT's |
How loud is 1 watt? I just wanted to ask because I connected the ohm sw2.2000 on a 45 watt kenwood kr-5150 and the meter was not even touching the 1 watt indicator and it was already loud. Not sure if the kenwood receiver was truthful but it was plenty loud at halfway mark of the volume control already.
The ohm sounds beautiful with the vintage kenwood by the way, warm but detailed with lots of bass and punchy sound, albeit a rich and forward sound. When I switched to the denon as preamp and the parasound hca 1500 however, the soundstage is deeper and wider, I'd blacker as well as the music is more transparent than the kenwood. |
1 watt into the Ohms,which are not highly efficient, will probably not even be audible or barely so. |
Drakef5, Most Ohm users, if not all, (and I think it is all for those who have tried) report very positive results when giving the Ohms more power. While waiting for your Parasound, why not try an Emotiva amp? 30 day return policy... |
1 watt into an Ohm is a SPL (sound Pressure Level) of about 87 dB at 1 meter. This is relatively inefficient. For example, a Klipshorn corner speaker has a SPL of 102 db- you could practically drive them with a flashlight. So double the power, dB goes up by about 3. So to go from 87 dB to 102 dB would require 32 watts in an Ohm., or 32x the power. This would be in an anechoic test chamber, without the affect of furniture, rugs, etc adsorbing the sound. And sound degrades quickly with distance, amplifiers clip at their limits, etc the power requirements are much more that the 32 watts. |
Thanks for the replies guys. @petepapp i do have the parasound amp and i like it better with the amp than just the receiver.
87 db at one meter is close to the threshold of hearing damage and with the sound of the ohms being magnified by the walls and surrounding environment i think that is plenty loud.
Anyway i just learned something about this expirement ...that ohms does not require big power to sing but blossoms with more.
It is a bliss if one is satisfied with a lower powered setup since its less hole in your wallet:). But...i guess this really is a sickness that i have where i am trying to extract every once of goodness that i can get with the ohms hence expirementation and less dollar in my pocket.
For now i will enjoy what i have until i get the itch again. |
I have driven my Ohms with 32 watt/ channel tube amp. Tubes will usually produce higher spl than ss at same output, but I did experience a couple of instances of amp clipping so in my experience there is a risk of equipment damage at this power level. |
I've also used a 30 wpc Jolida hybrid with my MWTs and while the sound was quite nice the amp clipped more than once while listening at reasonable levels. Obviously, care needs to be taken when putting together any system but lower-powered amps with Ohms line may not be the best match. YMMV of course. |
Dsremer - Thanks a bunch for chiming in, your posts were very helpful. The AVMs, Merrils and other Hypex-based Class D amps are just too expensive for me at this time, but the D-Sonics might be a nice compromise between price, power, and sonics. I am looking at the 1500 watt/channel stereo model. The amps I had on loan were the Arion Audio RS-500 monos. Sounded fantastic, as I have stated. But, you know, if 500 watts is great, 1500 watts mmust be 3 X as great! |
Drakef5: An audio club budy of mine uses a Denon AVR, suplemented by Crown power amps (not sure which ones) to power his own design speakers and subwoofers. Plenty of oomph, but I suspect they lack the refinement that an amp designed for audiophiles would have. If you decide to try the Crowns, make sure you can try them out in your system and that they can be returned if you're not happy with the results. |