Hey CDMA,
Sorry, I am not at all familiar with Dunlavy cables. But, I've the Aleph 3 and used it with various speakers with various speaker cables. I think I had better luck regarding cable matching when I treated the Aleph as if it is a lower power tube amp than a muscle amp as it isn't one. I think twisted pair CAT 5 cables should serve you very well. |
Cdma: Sorry for sidetracking your thread with that "long" response to Felix. However, i hope that the link to the Stereophile review of the Dunlavy's is new to you ( and possibly others ) and comes in handy. It might at least make for a refresher in terms of the truly excellent performance that they are capable of IF properly set up. Having said that, I'm glad to see that you are experimenting and learning on your own. As mentioned, a speaker with a relatively wide horizontal dispersion will not benefit that much from increased toe-in. That is, unless the installation is far less than optimum to begin with ( as i had previously mentioned ). Your first hand experience and experimentation with the Dunlavy's basically verifies the point that i was trying to drive home to Felix in the above post. Whereas your PSB's were a much "beamier" speaker at high frequencies, the Dunlavy only suffers from this phenomena above appr 10 KHz or so. As far as the bass response and room loading characteristics go, you will have to experiment with speaker placement AND your seated listening position at the same time. As mentioned, some reasonably priced test equipment will help take some of the guesswork out of the equation, but you can rely on your ears until you are able to pick this stuff up. I would suggest taking a look at a post that i made in a thread titled How to arrange my speakers. I have used this method to a great extent and it has always worked pretty well, even in odd shaped rooms with unconventional speakers. I'm not saying that this method is "better" than the Cardas, Wilson, Audio Physics, etc.. methods, but, it will at least get you close in any size / shape room without having to do ANY math. Other than that, you may end up needing either a consultation with a professional acoustician or to invest in a program called Computer Aided Room Acoustics or "CARA" for short. I know that Kal Rubinson did a review of CARA for Stereophile of this computer based room optimization software and was VERY happy with the results. Not only was he able to improve the performance of his system taking advantage of what CARA told him to do, he learned a lot about his room and its' acoustics along the way. At least that's what i gathered from his review : ) Sean > |
Felix: I have no "fear" of any comments or corrections that you would like to deliver. As such, have at it. As i've mentioned before, i would prefer to be publicly corrected than to be mis-informed and spreading dis-information. As far as the "acoustic blanket" goes, this is used to minimize / damp baffle reflections and diffraction, not to "limit dispersion patterns". This also helps to flatten any irregularities in the frequency response IF the material ( usually foam or felt ) is properly applied AND the correct type of materials are selected. If one did attempt to "limit dispersion" using this method, nearfield reflections would occur with the resultant irregularities in frequency response taking place. For the record, Dunlavy evidently didn't test each pair of speakers as well as he thought prior to shipping them out the door as Stereophile did make mention of just those problems when making their test measurements. As a point of reference that i present to help support my previous statements, here are several quotes as taken from the Stereophile review of the Dunlavy SC IVA's: "Remove the grille and you'll note the same symmetrical arrangement of midrange drivers and woofers around the centrally located tweeter, with heavy felt around the tweeter and midrange (a method of diffraction control for which Dunlavy holds the patent)." "There are a couple of early reflections noticeable, however, which I assume are from the relatively firm felt used in the tweeter's acoustic environment. These give rise to the small ripples seen in the on-axis frequency response, which are subjectively benign." If your comments were correct regarding minimized horizontal dispersion for all MTM arrays and all versions of the Dunlavy products, you would literally have a speaker that had pinpoint dispersion characteristics. Since the MTM / D'Appolito design displays limited vertical dispersion by its' very nature, your comments regarding limited horizontal dispersion would mean that the speakers would have to be aimed directly at the listeners' ears in order to maintain any type of linear frequency response. While this might have been the case with some of the earlier SC IV's, Dunlavy later corrected this by revising the mids and tweeters that were used, completely re-designing the crossover, fine-tuning how the felt around those drivers was applied and changing all four woofers used. Stereophile makes mention of both the design changes and the differences in performance that resulted in these comments being made in the above referenced article: "The tweeter and midrange units are the same in the SC-IV and the SC-IV/A, but each has gone through three or four generations of improvements since the original SC-IV. (The tweeters and midrange drivers in my SC-IV's are the latest versions.)" "However, there are many ways of designing and executing a minimum-phase crossover, and the SC-IV/A's crossover uses almost twice as many components as the one for the SC-IV." "Where the SC-IV/A's did score over the SC-IV's was in their tonal balance and imaging for the off-center listener." "Central imaging had that "holographic" quality, but the sound for the off-center listener didn't seem to fall off as much as with the SC-IV's." As such, one can see that the limited horizontal dispersion that you make reference to was primarily due to the poor design of the original crossover and the selection of lower quality drivers that Dunlavy made use of in their earlier production runs. As such, i must assume that the comments that you made are based on familiarity with the earliest, lowest performance versions of the SC IV's. As can be seen in the previous Stereophile comments, these obviously lacked any of the later design revisions. If you are familiar with the later SC IV's or SC IVA's, then your comments seem even more out of place according to what Stereophile reported. While i do not know the production date of the SC IV's that i worked with, i do know that i didn't experience the majority of problems that you mentioned. If i had, i wouldn't have said what i did about placement suggestions. Nor have i experienced that phenomena ( limited horizontal dispersion ) with other MTM designs. For the record, most all of the information that i've presented here can be found in any decent manual dealing with speaker design. By no means am i repeating anything other than common knowledge that is available to anyone willing to read and learn. Other than that, the custom designed quad-amped speakers that i referenced in my prior post made note of all of the design flaws of the Dunlavy's that Stereophile made mention of and took them into consideration when the project was initially started. By combining these corrective steps with all of the high points of the Dunlavy's and going even a few steps beyond that point, we've never run into any of the problems that you stated. This is true even though the inspiration for such a design was directly borrowed from much of Dunlavy's own R&D and finished products. As far as your comments pertaining to what passes as "expert advice" here, nobody here claims to be an expert. At least not as far as i know. We are simply a community of music / audio lovers (with a few video fanatics thrown in for good measure) sharing various points of view from various perspectives and backgrounds. Sometimes there is mass agreement, sometimes we are all on our own in terms of personal beliefs / experiences. Other than that, i'm glad that you were able to find a forum that you are comfortable with and can call "home". Tell Jasmine i said "hi" and don't forget to kick the dog on the way out : ) Sean > |
The solution will be found when you control and redirect the now out of accoustic phase woofers. These speakers because of the floor ceiling disparity will never be able to allow the wave launch of the two drivers to meld and reinforce each other as one. These phase relationships will be around even after you change wire or amps. The problem will still exist. Try the baffles and then move onto the ceiling wall angles... Tom |
Sean & Felix
I just took off the grille and checked. I think, for mids, the felt is designed to limit both vertical and horizontal dispersion equally and for tweeter, the felt limits a little bit more vertical dispersion than horizotal dispersion. I guess that this patented design explained why the first direction is still kinda under control in my setup (2.5' from side wall and not toe-in). Last night I tried the toe-in. Just like my past experince, I can not experience any expected improvemnt. When I toed in PSB, I can experinece much stronger treble energy and a little bit better image but not SC-4. Maybe I should try it again ! I did find one thing, my old listening spot seems to be in the null of bass band. If I moved 0.5' forward or 1' backward, the bass is mucg stronger. BTW, as mentined, I do not have back wall to my seat so I wonder if it is from the standing wave caused by the reflection from the front wall or the kitchen. very interesting ! |
Viggen,
you thought sounds like "you know what you are talking about" to me. Did you imply something like Z6 or Z8 ? I know low resistanve is better, how about capacitance and inductance ? Which direction is better ? I found www.audionet.de/pdf/english/highendnews_amp1.pdf. The reviewer switched from midnight to Z6 and gained significant improvement. What do you think ? Thanks ! |
"Based on the experience mentioned above, I will only add that if one can't place the speakers along the long wall and minimize the amount of "clutter" between the speakers so that they can directly "communicate" from side to side, measurable toe-in will probably be a necessity. MTM speakers are designed to "spray" the sound out horizontally and if the speakers can't "blend in the middle" due to obstructions, one must force the situation by aiming them inwards to the point that the signals are forced to blend together."
The very reason why the drives in the large DAL designs are surrounded in felt is to minimize horizontal dispersion. As such, the speakers are extremely directional and need toe-in to focus the sound toward the listening seat. This is not something that can be debated, Sean, and if you were familiar with the SC-IV's, you'd know this all too well.
I really don't feel right exploring your comments at length (like you know I can), as this forum seems like a happy place and I'm much more comfortable in an unmoderated environment. Suffice it to say that I'm absolutely astonished by the kind of "expertise" I see presented here as actual experience.
Best Wishes,
Felix
www.audioannex.com |
I have worked with one set of the original SC IV's ( not the re-designed "A" models ) a while back, another set of speakers* that are very similar in design but FAR more advanced and "tweaky" and several "good sized" speakers using MTM designs. As such, that experience is what i based my comments on.
Based on the experience mentioned above, I will only add that if one can't place the speakers along the long wall and minimize the amount of "clutter" between the speakers so that they can directly "communicate" from side to side, measurable toe-in will probably be a necessity. MTM speakers are designed to "spray" the sound out horizontally and if the speakers can't "blend in the middle" due to obstructions, one must force the situation by aiming them inwards to the point that the signals are forced to blend together.
Having said that, I'm sure that Felix' experience with the Dunlavy's that he owns is 100% accurate. I'm also quite sure that John Dunlavy knew his product well enough to know how they work best and included his thoughts in the speaker manual. The only variables to the two above situations are that room acoustics do differ, along with the constraints of various installations. This is not to mention that one can enjoy / prefer slightly different presentations from someone else using the same speakers. As such, one WILL have to experiment ( to a much greater extent ) with speaker placement when using a "less than conventional" speaker design in order to find out what works best for them in their room. I don't know of any speaker made that can be placed in one given set of positions, regardless of room layout or size, and obtain universally repeatable performance. Some basic suggestions may provide pretty consistent results, but there will always be exceptions to the rule due to the above mentioned variables. In other words, one size does NOT fit all. Sean
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* A custom built set of speakers using similar driver layout using as good or better quality drivers, far more advanced individual cabinetry for each driver, better quality internal wiring, no passive crossover components and active quad-amplification. |
"By mirror imaged, i was referring to the design of each individual speaker as a vertical array, not from side to side. The drivers below the tweeter are a mirror image of the drivers above the tweeter, etc..."
Fair enough, but that's not what mirror-imaged means.
"My experience with toe-in on a speaker of this nature is that it DRASTICALLY limits the size / width of the soundstage while producing a much "hotter" high end and tonally forward presentation. While the center image is increased with toe-in, a certain amount of air / space between instruments is also lost due to increased focusing of the signal into a smaller area. In such a situation, sitting further back ( beyond the distance of creating an equilateral "V" with the speakers ) will produce an increased sensation of the performers being front and center rather than if the speakers were not toe'd in and you were sitting in an equilateral triangle."
AFAIK, you've never setup a pair of SC-IV's. The constraints you describe are somewhat ambitious given the actual performance of the product.
"Obviously, personal preference will dictate what works best for you in your system but the experience of those like Felix who have quite a bit of experience with a product of this type should not be disregarded. Even if we do have different personal preferences : )"
I appreciate that, Sean, but this really isn't an issue of personal preference unless one has a strong desire to live with a distinct lack of bass and focus, basically negating the fundamental design goals of the speakers. There's a very good reason as to why the owner's manual goes into detail illustrating specific placement options.
Best Wishes,
Felix
www.audioannex.com
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Felix: By mirror imaged, i was referring to the design of each individual speaker as a vertical array, not from side to side. The drivers below the tweeter are a mirror image of the drivers above the tweeter, etc...
As far as the controlled dispersion pattern goes, much of this has to do with the MTM type driver layout and the "acoustic blanket" ( damping material around the high / mid drivers ) that Dunlavy makes use of. All MTM arrays will demonstrate limited vertical dispersion. How limited the vertical dispersion is will have to do with the spacing between the drivers and quantity of drivers used in such an array.
My experience with toe-in on a speaker of this nature is that it DRASTICALLY limits the size / width of the soundstage while producing a much "hotter" high end and tonally forward presentation. Increased toe-in will also limit side-wall reflections, so it would provide better performance in non-long wall installations. While the center image is increased with toe-in, a certain amount of air / space between instruments is also lost due to increased focusing of the signal into a smaller area. In such a situation, sitting further back ( beyond the distance of creating an equilateral "V" with the speakers ) will produce an increased sensation of the performers being front and center rather than if the speakers were not toe'd in and you were sitting in an equilateral triangle. Obviously, personal preference will dictate what works best for you in your system but the experience of those like Felix who have quite a bit of experience with a product of this type should not be disregarded. Even if we do have different personal preferences : ) Sean
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Sorry to sort of go off the subject, but I really think the speaker cable needs to be changed. I think you need cables that has more emphasis in "speed" rather than "guts". Sorry if I sound like I don't know what I am talking about. Just think, "low gauge" and "low capacitence". |
"What is the theorectical benefit of toe-in ? image and directional treble ?"
Yes, the speakers are extremely directional and have very narrow and well-controlled dispersion characteristics. That's one of the reason why they can be placed fairly close to the room's boundaries without encountering severely adverse effects. Direct toe-in helps the speakers achieve the amazing focus that makes them very special.
I became interested in this thread, because I encountered a similar problem when I first setup my SC-IV's. I placed them in a manner very similar to yours, in a room almost the same size and shape, and had virtually no bass even though I was driving them with a KSA-150. It took me almost a week to open the owner's manual (audiophile pride, you know) and set them up per the manufacturer's instructions. The transformation in the sound was truly spectacular. Since then, I've setup literally dozens of pairs of Dunlavy's, and all of them sounded best with long wall placement.
If there's absolutely no way for you to utilize the long wall, I'd suggest placing your seat directly against the back wall with the speakers moved half-way into the room, as a starting point.
Best Wishes,
Felix
www.audioannex.com |
Hi Felix, I did try following the manual and the essential points (wide separation and distance) but the long wall setup and toe-in. Long wall setup is not the option for my listening room arrangement. In my past experience, I do not like the sound when PSB is toed in. What is the theorectical benefit of toe-in ? image and directional treble ? not bass I guess. Thanks ! |
Cdma..I have owned SC4;s since 94.. I have the same problem as you in my room. Lower mid bass suckout? I have found the distance from the bottom woofer and the floor and the top woofer and the ceiling create unusual loading effects in soom rooms. Some of these problems can be largely mitigated. E-mail me if you like for more info..Tom |
"Due to the wide horizontal ( but limited vertical ) dispersion of the mirror imaged design that the Dunlavy's use, you'll probably need to pay close attention to the primary points of reflection on the side walls AND toe the speakers in. This type of design typically works best with no toe-in, but your installation somewhat forces you to do so."
I'm not sure if one could call DAL's mirror-imaged, as that implied that some of the drivers are offset, and that is not the case with the speakers. In terms of setup, the DAL's are meant to be toed-into the listening seat rather profoundly. As mentioned, they should be setup on the long wall, and I think the original poster should try that placemat before attempting to implement other corrective measures. Ideally, they should be spread farther apart than the distance from the listening seat to *each* speaker. The setup section in the owner's manual is fairly complete and is best followed for optimal performance.
Best Wishes,
Felix
www.audioannex.com |
As mentioned in that same thread, the commonly accepted "theory" is that a 1 to 10 ratio is considered "good". This would mean that a 500 ohm output impedance of a source or preamp should see an input impedance ( from preamp or power amp ) of at least 5000 ohms. Anything above that ratio is simply icing on the cake. As such, i don't see that as being a problem.
I would not doubt that you find the Dunlavy / Pass combo "lean", especially given your past combo, speaker placement and room lay-out. The Dunlavy's are known for being "faster" rather than "weighty" bass ( same with the Pass gear ). On top of that, you've literally got very little to NO room reinforcement taking place. As such, you really do need to experiment with speaker placement and / or seated listening position. Moving the speaker or seat back or forward just a bit may help land you in a specific node that will give you more apparent bass. This is the approach that Audio Physic's uses for speaker placement and you might be able to find some info on their website. Picking up an SPL meter and calibration disc ( try Rives Audio ) can help verify your results in a less subjective manner.
As to the digital gear, i am more-so talking about the Marantz but would include the entire digital front end in general. Then again, what one likes / uses for a digital front end can be rather subjective ( as is almost all of audio ) and you might find that you are happy with what you have after doing some comparisons. My thoughts of such a combo are that it would sound rather stripped and sterile, lacking liquidity, warmth, body and soul. One would have great "clarity", but overall "musicality" and "toe tap factor" would not be as high as it should be.
I would suggest working on your tonal balance problem first and then go from there. Then again, changing your digital front end might resolve the lack of extension and warmth that you seem to be lacking. I do think that the two problems "probably" are somewhat related, but i'm 100% certain that improved speaker placement can give you instant results without spending any more money. Sean
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Thanks again !
I did see Drubin's comment on impedance match !
I got a ratio of 46 = 23k/0.5k, how is it ? Maybe this number accounts for a little bit bass shy. AI L-1 or Aleph P of my once candidate won't improve this ratio. I did do something on the primary points of my back and side walls, the reflection is kinda under the controll and no toe-in is applied.
About my source, do you mean cd-63 or cd-63 plus AA gears ?
Do you think a Perpetual p3a replaceing DDE with some upsampling trick will help ? |
Cdma: Due to the wide horizontal ( but limited vertical ) dispersion of the mirror imaged design that the Dunlavy's use, you'll probably need to pay close attention to the primary points of reflection on the side walls AND toe the speakers in. This type of design typically works best with no toe-in, but your installation somewhat forces you to do so.
As a side note, you might be running into impedance related problems with the ARC preamp and the Aleph amp. This is discussed in another current thread and the Aleph's are specifically mentioned in terms of having problems with tube and / or passive based preamps ( for lack of a more universal term ). This is something that you might want to check into also as it could be affecting what you are hearing / the synergy between components.
Other than that, my thoughts are that your source is now the weak spot within your system in terms of electronics. I know that you probably just dumped a ton of cash on this stuff, but i can see some further expenditures coming up in the near future for you : ) Sean
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Thanks for the responses !
Drubin, I guess what I want to know is if A/D combo is what it should be or a little bit bass-shy, especially both KSA and PSB are known for their bass performance or too exagerated. In fact I'm not sure if I need more power. Right now my preamp points to 10-11 o'clock position in pretty loud listening leve while the previous Aleph owner pointed to 3 o'clock driving Maggies 3.6.
Sean, yes it is big change (and improvement). In fact, I like them very much. I just want to know if the bass of my previous system is too exagerated (or slow and muddy) or the current one is just right (quick and tight). Thanks for your opinion !
My cable is Audioquest midnight-2 driving by ARC LS-3B, AA DTI-PRO32, DDE V3.0 and Maratz CD-63. The roomm is about 16Wx24Lx17H. The speakers are along the short wall (not as suggested, I know) but 10.5' apart. 2.5' from the side wall, 7' form the back wall without toe-in. There is no front wall since it faces a open dinette/kitchen (15'wx22'L). The listening position iss about 11' from the center of the speakes. Is it good or any improvemnt can be made except "along the longwall" ? Thanks ! |
I can see why you would think that you "lost" bass. In effect, you did. Having said that, "quantity" does not always equal "quality".
Pass amps are NOT "bass monsters", especially the Aleph series.
Dunlavy's are known for having very quick and tight bass, not the bloated thud that most vented designs offer.
As such, you went from an amp that is known for having gobs of power / current with phenomenal bottom end driving speakers that are slow, thick and muddy to an amp that is somewhat lean and speakers that are much more defined and quicker. Obviously, that is quite a big change.
I would suggest working with speaker placement and give yourself a chance to get used to the new system. I'm not suggesting that you'll like this set-up better simply by getting used to it, but it IS a VERY different system.
So that we may be able to offer more informed opinions as to what might help you out:
1) what are you running for speaker cables ?
2) how big is the room that the Dunlavy's are in ?
3) how far apart are the Dunlavy's from each other, the side walls and the front wall ?
The more info that you can give us, the more likely the comments are to be somewhat helpful and accurate. Sean
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The Aleph amps are not bass champs whereas Krell is. And the Dunlavy may have less *apparent * bass than your PSBs.
I also think you need more power than the Aleph 5 for your speakers, though you can certainly live with it for a while. It should be superb in many respects. |
