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Need your thoughts on mating a Levinson #532H amp for the low frequencies, to an amp that will mate well and shine in the mid/high region. I'm not really trying to accomplish anything in particular, just trying to improve and fine tune something that is already grand. I do own two quality pairs of speaker cables, a spare matching balanced interconnect, a spare matching Shunyada power cord, and my preamp has two pairs of balanced outputs, so all I really need is the right amp and schuzam nirvana, or maybe not.
See my profile for system details.
Regards Tim
Edits: 05/17/12 05/18/12Follow Ups:
sorry, couldn't resist :)
do not just separate the lows from the highs, they also perform impedance corection and equalization (some time additive, sometimes subtractive, so simply adding an external crossover and bypassing the the passive in the box usually results in inferior performance.
But with patience and engineering and measurements the results you get from a biamped system is much better sound because of (1) lowered distortion - created by the saturation passive inductors; (2) better woofer control - because of the eliminatin of series resistance; (3) better matching of gains - no need for a resistive L pad for the tweeter - throw in a nicwe low powered Tube Amp instead; (4) more headroom (because of the splitting of the signal energies going to the amplifiers (5) more precise control of EQ.
When an electronic EQ is designed by the manuafacturer for a loudspeaker they can (but not usually implemented) adjust for the thermal non linear behavior of components (this can be done in a passive crossover also - though with lot's of limitations).
Why loudspeaker designers (or high end consumers) do not embrace the idea of biamping is an interesting discussion.
Would Wilson Audio (for example) be abnle to make a beter reference standard loudspeaker if they they used electronic crossovers and amplifiers? No doubt...
Would Dealers want to sell it? maybe not... they miss the (potential revenue of amplifiers, amplifier upgrades, cables , etc.
Would Audiophiles buy it? maybe not... We miss the fun of rolling your own.
Some companies emprace electronic crossovers for their product (ATC, B&O, Meridian)
Some companies (that you would expect to do not) McIntosh?
Three most important things in Audio reproduction: Keep the noise levels low, the power high and the room diffuse.
It's funny you should say "throw in a nice low powered Tube Amp instead", since i just bi-amped my Wharfedale EVO 2 30's normally being powered by just Quicksilver Mini Mites, with my Jolida JD1501 which was just sitting idle. The Jolida's volume acts as a trim for the bass & the Quicksilver's ad more definition to the mids & hi's. I feel i now have the best of 2 worlds...tube for highs & mids & Solid state & tube pre-amp for the bass! However the OP has a 300wpc amp & IDK, maybe a low powered tube amp would'nt quite match?
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If you cross over before the power amps so you can hook the drivers directly to the amps it can be worth it. Not a slam dunk, still a lot of things to consider including how the original crossovers compensate for anomalies in the drivers and cabinets, but it can work very well.
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...that passive crossovers generally are NOT simple devices. Most of them contain simple networks to correct for impedance rises and dips, phase errors, etc. Bypassing this stuff generally makes the speaker sound worse, not better.
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Tin-eared audiofool, former fotografer, and terrible competitive-pistol shootist.
"Everything that can be counted does not necessarily count; everything that counts cannot necessarily be counted." Albert Einstein.
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you. . . "that passive crossovers generally are NOT simple devices. Most of them contain simple networks to correct for impedance rises and dips, phase errors, etc."
me .. "Not a slam dunk, still a lot of things to consider including how the original crossovers compensate for anomalies in the drivers and cabinets"
pretty much the same thing don't you think?
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Tin-eared audiofool, former fotografer, and terrible competitive-pistol shootist.
"Everything that can be counted does not necessarily count; everything that counts cannot necessarily be counted." Albert Einstein.
These would appear to be perfect targets for active bi-amping as Jay Buridan has suggested. 4LR slopes at all points.I'll assume that the double terminals access the woofers, and then the MR and tweeters combined. So long as the crossover between the woofers and MR is below 500hz, ideally down around 300Hz, then bi-amping should be a big step-up in quality.
But, are the claimed 4th order slopes the electrical slopes of each crossover point's OR are they the final acoustic slopes of the output from each driver? Several posters clearly assume that they are the same thing, when they very rarely are on passive xover speakers.
That is, a combination of an electrical slope from the passive crossover and the acoustic behaviour of each driver in its own enclosure.
Viz. the high-pass slope of the MR driver, which in the Salons has its own smallish enclosure and may well have a useful 2nd-order sealed Vb high-pass slope to which a 2nd order electrical slope was added.
Even were you to remove the electrical passive crossover, adding a standard 4th-LR order active crossover would give you a 6th order high pass and likely a 4th order low-pass for the woofer/s. This would NOT give the same blend as Revel would have worked so hard for, including the matching drivers to 0.5db via the crossover in YOUR speakers that they also laboured to achieve. There is also possibly some trimming of the crossover components to match the initial slopes from the driver/crossover combination.
IF the electrical crossover for the woofer/s had impedance rise Eq built-in to the crossover and not across the woofer/s terminals then the tonal balance will shift down there as well.
In short, I am not persuaded that an active crossover - UNLESS it was built as a bespoke item for YOUR speakers and each driver in them, to match in the same ways covered above - would be a good idea, at all.
You could get someone to measure the transfer function of each of your Salon's Bass/MR crossover and then try to build an active crossover that matches that now in use in each speaker, they won't be the same.
If it were me I would ask Revel precisely these questions and ask them for what THEY think.
It is conventional wisdom that a bigger amp, by at least 6dbw, is a better option. And it will sound better.
IME adding a second amp matching amp ( or one with level controls) is itself a potential upgrade. It certainly won't sound worse. And the MR treble amp OUGHT to be loafing and that range ought to sound sweeter.
So now you have THREE options
1. A bigger power amp, less what you get for the existing power amp IF you sell it. Plus what you lose on it if it's at all recent. This will sound better
2. Retain the existing voicing by bi-amping passively, and buy another matching power amp, likely the cheapest and still a very good probability of improvement. You retain the existing power losses, so you won't get as much headroom improvement as 1 or 3.
3. Retain the existing voicing by having a bespoke active crossover built and buy a midrange-treble amp (a matching one OR a dedicated Class-A, tubed, even SET sweety pie). Likely to be the most expensive option and a less certain outcome.
Note that a post in response is preferred.
Warmest
Timothy Bailey
The Skyptical Mensurer and Audio Scrounger
And gladly would he learn and gladly teach - Chaucer. ;-)!
'Still not saluting.'
Edits: 05/19/12
I'd be curious what you're biamping and what the crossover point is and whether you are just biamping with split inputs and the stock passive cross overs.. A good passive crossover doesn't just cross over, it equalizes the drivers in the system. If an external, generic, electronic crossover is used it won't have this equalization. If the crossover is very low this probably is not as important. And if you're going through the stock passsive cross over you're OK.
with good attenuators
...that is, continuing to use the crossovers in the speakers.
If he wanted to actively biamp, he'd also have to determine how to bypass the crossovers in the speakers.
Of course, we're all smart enough to know that one doesn't combine an active x-over driving the amps AND the passive crossovers in the same speaker.
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Tin-eared audiofool, former fotografer, and terrible competitive-pistol shootist.
"Everything that can be counted does not necessarily count; everything that counts cannot necessarily be counted." Albert Einstein.
What would happen if you sent low frequencies to the low passive posts and the already separated mids/hi to the top passive binding posts?
Steve
...and lowering the lo-pass point (compared with the probably-carefully-chosen FPs the designer effected), thereby creating a substantial dip in output around the FP(s). Also, the the filters' slopes would be additive, so if the passive x-over had two 2nd-order slopes and one used 2nd-order slopes in the active filter, one would end up with 4th-order slopes--in addition to the 'hole in the middle'.
Of course, one could in the active filter use 1st-order slopes so as NOT to add much filtering and set the filterpoints 2 or 3 octaves away from the passive FPs so as to reduce the negative effects of double filtering, but then why bother? One would have gone to the cost and effort of buying the filter, cables, and maybe the extra amp(s), suffering the negative sonic effects of the active filter--and they ALL have negative effects--only to end up with still-bad double filtering.
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Tin-eared audiofool, former fotografer, and terrible competitive-pistol shootist.
"Everything that can be counted does not necessarily count; everything that counts cannot necessarily be counted." Albert Einstein.
Since the amps won't be identical he will need a way to adjust gain.
...is perhaps the last device I'd add to do that.
The first device would be a level control added to the higher-gain amp.
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Tin-eared audiofool, former fotografer, and terrible competitive-pistol shootist.
"Everything that can be counted does not necessarily count; everything that counts cannot necessarily be counted." Albert Einstein.
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I always get better (to MY ears) results when bi-wiring rather than bi-amping.
I think it depends on your speakers. For multi crossover speakers like Legacy, bi-amping is recommended by the manufacturer. For other spekars, bi-wiring may indeed be better.
"What this country needs is a good 5 watt amplifier!" (Paul Klipsch)
Wilson Audio does not recommend bi-amping their speakers. Just an aside
Alan
Are you bi-wiring now? If not do that. I'm a bi-amper and believe in horizontal bi-amp. It's critical to gain/sensivity/ impedance match the two amps. I use two of the same brand of amp where those stats are about identical. I like the improvement of my bi-amp and wouldn't go back. The most noticable improverment was in image quality; both width and depth. I like the idea that the amps now each see one impedance peak and load and not two (I use two way speakers) I think this improves power transfer.
ET
Yes I am biwiring now and with much improved results over the MIT Oracles by them selves. It is the system with the Revel Salon ones, they have been slightly upgraded with a tweeter mod. I also built custom stands that set the cabinets on three heavy cones rather than four puny spikes and heavy aluminum cross members. Also built heavy platforms as the prodigious bass the speakers are capable of was activating the floor, isolating them made for punchier and better defined bass.
I was not considering an active cross over. To answer another responders question, I have listened to the Levinson reference #53's and thought there were fine but somewhat sterile sounding for my tastes, not really what I would call eventful, maybe thats what an amp should sound like, ( very neutral without bringing attention to them selves ). I have considered a sweet tube amp for the upper range but understand that may be harder to get the right match, I would also have to alter my listening habits as I have the system in the middle of the house and listen and leave it on constantly.
I think bi-amping works fine with the speakers internal crossover. If you did by an active crossover you'd really need to connect the amps directly to the drivers for proper implementation. Good luck with your quest.
ET
I have a pair of Legacy Audio Signature IIIs, which are a tough load for amplifiers, even though they are 93 db@1 watt. They are nominal 4 ohm load, and were measured as low as 1.1 ohms at 65Hz.
The owner’s manual suggest vertical bi-ampig the speakers. First, it raises the overall nominal impedance to 6 ohms from 4 ohms, and resolves the back EMF for the high level input. So, I have the speakers vertically bi-amped with a pair of Threshold SA/3 50 wpc class A amplifiers. This sounds quite a bit better than using a single STASIS 2 Threshold (200 wpc class A/B).
"What this country needs is a good 5 watt amplifier!" (Paul Klipsch)
I used to sell those. I didn't realize they dipped that low at 65. I think though that any style of bi-amp will raise the impedance to 6. For me having two amps of different power levels yet the same impedance/sensitivity and gain made horizontal the only option. I'm not surprised with your results based on that info and the Thresholds are nice, gutsy and plenty of power for the application. I'm glad you found a scenario that works well. Enjoy!
ET
There's lots to read in the archives, search 'Bi-amp' authored by Charles Hansen and others.
Have fun
I tried bi-amping my Tannoy Definition D500 speakers several years ago using a CJ Premier 11a tube amp up top and the CJ MF2250A solid-state amp for the lower freqs. It certainly improved upon the less than stellar bass from the Premier 11a tube amp but there was something about that setup that didn't sound quite right after a while.
I later went for a larger tube amp. For me and my limited bi-amping experience, I found that a single larger/better amp was the way to go. YMMV
And for the record, I'm not a big fan of subwoofers. I'd rather have a larger speaker with a broader range than trying to make up the difference with subwoofers.
Over the years, I've tried this at various times, sometimes with great success, sometimes not.
My first effort was in the early 70s, using a Phase Linear 400 on the mid-range screens of my Infinity Servo-Statiks and a Marantz 8B on the tweeters.
Using the finest electronic crossovers of the times and specialized amps for certain areas, I would occasionally try it again up until the late 80s with various speakers.
The problem was that I could always get a very impressive sound, even a spectacular sound technically, but not one that really hung together from top to bottom and made music rather than cool audiophile sounds - i.e., better bass, more extended treble, etc. So I'd use it for a while, and then one day get tired of the audiophile sound and go for a different set-up.
Ultimately, it always came down to using two of the same amps if I were to be satisfied musically.
I don't know for certain, but I've come to think it was the difference in input impedance/loading, transfer characteristics, dynamic capabilities, and phase response. But that's only a rationalization for why I never got it to work, nor why I never heard it work anywhere else, especially at manufacturer & dealer demos.
When I say 'work', I don't mean that technically it didn't work. I'm referring to more of an organically cohesive musical quality. Maybe even what's called 'continuousness' in certain quarters these days.
Best regards,
Jim Smith
In fact, they generally say "Wow!". :-))
Then again, I have always used amps from the same family with my active Maggies - first 2-way, about 12 years ago ... and then 3-way, from about 10 years ago.
Melbourne, Oz is probably a bit inconvenient for you to have a listen to my Frankenpans ... but maybe you should contact hemholtz, in Chicago, who uses a DEQX for his 3-way active Maggies (3.5s supplemented by 2 x T-IVa bass panel per side).
Regards,
Andy
I know EXACTLY what you mean.
"Wow", "Spectacular", etc, were the common reactions.
And the systems deserved those comments from a technical aspect.
But playing master tapes I knew, it was only after a period of time when the special effects wore off that finally I had to find similar amps so that the music could hang together.
But the wow part is big fun for a while.
But then, maybe it was just my quirk.
Some speakers that I am referring to are Bozaks, Tannoys, Avantgardes, Tympani ICs, IDs, IIIAs, Infinity SS-1s, RS-1Bs, The original full range Apogees, Levinson HQDs, Goldmund Apologues, various custom jobs, etc.
So this observation didn't occur over a single instance. It was actually over dozens of systems, some of which I assembled and some of which various dealers & manufacturers assembled. All had that WOW factor. They were amazing really.
It wan only when the different capabilities and characteristics of the various amplifiers finally manifested themselves as a source of ultimate dissactisfaction with the gestalt of the music, that it became noticeable to musicians and audiophiles whose sensitivities ran in that direction.
For others, for whom the amazing audiophile sound is the ultimate goal, the wow factor lives on to this day, and they don't value that last vestige of compellingly involving music reproduction.
Just different strokes, I guess.
I will say that I don't know a single knowledgeable industry veteran who'd prefer to mix 'n match amps.
They probably exist - I just don't them.
For that matter, while we're opening cans of worms, I've never heard a digitally eq'd system that resembled live music either. In this case, I suspect they can.
But the people I've worked with used the digital eq as a sort of panacea, instead of working fully on the acoustic wave-launch and reception of it at the seat BEFORE the eq is applied.
Please note that I am not against it at all. I AM against it becoming a short cut, bypassing the"organic' foundational things that should be accomplished first. Such systems always fall far short of what their potential could have been.
Best regards,
Jim Smith
Thanks Jim and andyr, two very interesting and thought provoking views. I think Jim has hit on what I experienced some years back when I tried a biamp system, ( two Levinson amps with the same output power but from different era's ) details and many sonic perimeters were improved but after a few months I heard what I would refer to as, for lack of better words, a slight blurring. I felt it was do to the two amps working at different speeds.
Jim, are you saying it's worth doing if I use two identical amps? or would I be better off pooling the cost and proceeds of both amps into one better amp? Of coarse that would hinge on what amp I would upgrade to. I did recently drag home many amps both tube and solid state some in the stupid price range over a period of about 18 months before settling on the 532H.
Thanks Tim
Sounds like you've got a good dealer to work with in trying out gear. Is it possible to bridge your 532h and add another 532 and use them as monoblocks? Might be a foolproof way to build on the Levinson's strengths without messing up a good thing. Others have suggested biwire as will I. If you're not biwiring and have only full range cables you could shotgun the two pairs of cable you mentioned and biwire that way, some fellas swear by this method. If all else fails pickup a pair of No.53s and enjoy. Ed
"that there Clarks an RRRR VVVV....don't get too attached...we're taking it with us when leave next month..."
Tim,
First, be sure you don't fall into the trap of using two lesser amps.
I always recommend one superior amp to two lesser ones.
Try to get the best amp that you can, and then get another one exactly like it.
I'm talking exactly - for example not a Pass X-250 and a Pass 250.5
Plus, IMO, there are some benefits to vertical bi-amplification. That means that one amp is used for upper and lower frequencies.
Then, not only do you get the benefits of bi-amplification that should sound coherent, you get the imaging benefits of what is essentially a pair of bi-amp monoblocks.
I cannot stress enough that the two amps be alike - even to the point of nearly the same production times. IF you are OCD like me you might make an innocent call to the factory to see if there have been any running un-anounced changes in a particular model you are considering. :)
All of this is IMO, of course, and others may vehemently disagree...
Best regards,
Jim Smith
Many industry professionals like yourself often speak of discontinuities between amps if different amps are chosen. Sorry Jim, but I feel that this is bunk. The reason for the discontinuity is often claimed to be the distortion charcteristics of said amps. Understandably. When the inherent distortions between driver types are magnitudes greater, why are people concerned with such claims? You have an 80 thousand dollar amp that for that kind of money should do it all (The Lars). So why the other amps? Sorry, but for 80 large I'd expect it to be IT, and for the band to appear live.
I have not seen or sold one of these amps in production-ready status, as they have been undergoing metalwork issues. Nor have I been promoting them here.As such, they didn't enter my mind when posting what I thought was a reasonable suggestion arising from years of experience voicing systems all over North America.
(FWIW - I use Quicksilver Mid-Mono amps, which sell for $1895/pr.)
What did enter my mind was the hundreds of systems set-up by audiophiles with mismatched amps that I've heard that were satisfying on a sound-effects-level, but never on a serving-the-music-level.
You can say all that you like in a disparaging manner - however, it was my intent to help and is the only reason I post here.
I do not and have not mentioned the products I sell. Well, actually that's not entirely true - I was asked various questions about Avantgardes when I was the distributor from 2000-2005 and - honestly speaking - get lots of e-mails even now. But I've always tried to reply as factually as possible, but minus the hype we sometimes see in certain quarters.
All that being said, I'd be surprised if your system is performing at more than 50% of its performance capabilities if you reject common-sense advice from folks with vastly more successful experience that you have.
But it your prerogative to make character insinuations.
When you think about the manufacturer/industry types who no longer post here, this is an excellent example of an inducement to just give up on providing advice.
Not that my advice is anything special, but I've been contributing here when I thought I could help for about 12 years. Go back and read what I've said and look for self-aggrandizement.
Not sure why, but the description of my advice as bunk especially hurts. Hopefully you were just having a bad day when you wrote it.
Best regards,
Jim Smith
Edits: 05/20/12 05/20/12
Well, that of course isn't the case, it's special indeed. How many other people set-up or advise on set-up of home audio systems professionally?
I've got a great dermatologist but he wouldn't be my first choice to fix a compound fracture. Even if he has the knowledge and license, I want the experience!
I got a kick out of your concern over running production changes. Now that IS something I'm intimately familiar with but most folks probably don't even know that there is such a thing let alone have a clue how production control is actually implemented or what the assumptions and tradeoffs are. Just your mentioning it says a great deal both about your thoroughness and perhaps the ilk of the problem.
Thanks for sharing from your unique perspective, I selfishly hope you keep it up!
Regards, Rick
Sorry Jim. I looked at your equipment listing and you have 5 or 6 different amps listed. From the hype surrounding The Lars, it should be the be all end all. As far as mismatching amps, many "industry professionals," Gizmo among them, have suggested push pull tubes for the lows and single ended tubes for the highs. Sounds like they have some 'splaining to do. At a yearly show in Dallas a manufacturer of an 8 K speaker provides the option of a single amp or tri amping his speakers. With a sand amp on the LF and the above listed amps on the mids and highs the system was open and coherent as all get out. It made the single amp running through his crossover sound closed in. Must have been dumb luck, or just my less informed knowledge of what sounds right.
Hey Ozzie,
Thanks so much for your note.
I really appreciate it.
After I went to Church, all I could think of was what an over-sensitive wuss I am.
And it's not exactly like we're worrying about world peace.
It's our hobby!
Thanks again!
Best regards,
Jim Smith
Well said Jim, always a gentleman.
Now that the scurmish has settled. I am curious about something that cost $80K which is a new amp of some sort, I guess, that is called a LARS. If it is not an amp - is it a speaker? Never heard of it but evidently Jim Smith has much to do with its production. Can anyone fill me in on this? Thanks in advance.
Steve
A lot of this info is out of date now.
That's because the owners went through some incredibly unfortunate personal health-related issues in the past 16 months, and the updates haven't been posted.
The first production models should ship in about 6 weeks.
They look a bit different, sound better, have more useable features that contribute to their sound as required by different speakers, and we will only import the power amps to the US, not the original integrateds.
http://www.thelars.se/
Best regards,
Jim Smith
Up front, my comment comes from a single speaker experience, not the wide range of system listening that Jim brings to the table.
Some years ago I owned one of the large Duntech models. In spite of the relatively highly rated efficiency (90 dB) I quickly learned that quality power was important. Those speakers allowed for bi-wiring (or what I called passive bi-amping), but not active bi-amping, at least not without opening up the cabinet to bypass the internal crossover.
A friend owned the same model Duntechs so we experimented with a number of amplifiers. At one point we tried a powerful tube amp on the mid/tweeter connection, with a substantial SS amp on the woofers, using a good quality pot in-line to equalize input. Nothing sounded better than his or my VTL amps running full range. Then we had an idea - we put his VTL 225s on the mid/tweets and my VTL 300s on the woofers. Now that was a WOW experience. Spacious, dynamic, effortless, by far exceeding anything else we'd tried so far as representing a real musical event.
But while the two VTL models were the same basic circuit design, there were two important differences. My 300s had larger output transformers and utilized KT-90 output tubes while my friend's 225s used EL-34s. In spite of being enraptured by that sound, it was not practical for me to live with four amps (the VTLs were monoblocs for those not familiar) and 32 output tubes in a house without air-conditioning. :^(
My point was in this case two very similar, although not identical, amps did provide the most musically rewarding results we heard. That was until a few years later when we both discovered the Halo JC-1 amps. That was the only one in our experience that competed with the passively bi-amped VTLs.
"For a nominal service fee,
you can reach nirvana tonight."
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