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Why bi-amp Mags?

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Posted on July 21, 2017 at 08:16:57
steve.sukiennik
Audiophile

Posts: 206
Location: Chicago, IL USA
Joined: May 23, 2017
 Great question,
I don't wanna hurt anyone's feelings but I asked Paul Heath Audio in Chgo some years back: Although bi-amping can be better it is best to spend all THAT money on ONE expensive clean amp. U can't create clarity w/3 dull, dirty & cheap components. Also upgrade the standard (passive) X-overs w/better pieces which will make a huge difference: foil coils & better caps & a way better amp. And bi-amping 2 of these way better amps together with a dirty electric (active) X-over = more dirt. This should save you's $$$$

 

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RE: Why bi-amp Mags?, posted on July 21, 2017 at 08:50:30
Davey
 Your whole premise is incorrect and based on a straw man argument. Unfortunately, you received some incorrect information from Paul Heath Audio.

Active crossovers are not "dirty" and three amps are not necessarily "dirty" relative to one.....or even more expensive.
And it's not possible to "upgrade" the standard crossover to a point even equal to removing it.

http://sound.whsites.net/bi-amp.htm
http://sound.whsites.net/bi-amp2.htm

Cheers,

Dave.

 

Completely agree., posted on July 21, 2017 at 09:46:51
grantv
Manufacturer

Posts: 7722
Location: B.C.
Joined: January 15, 2002
 And further, there are those with the financial resources to allow for 2 good amps without a set budget. If you said you have a budget of say $5000 for amp(s) and xover (upgraded parts or electronic to replace with bi-amping), then >maybe< there would be a legit point (still not IMO, but others may feel different).

 

RE: Why bi-amp Mags?, posted on July 21, 2017 at 10:38:58
BDP24
Audiophile

Posts: 1070
Location: Vancouver, Washington
Joined: September 12, 2013
 Steve---As Dave and Grant said, your premise is full of false assumptions, premises, and information. Nothing personal! Magnepan themselves recommended the Tympani models be bi-amped for ultimate performance. There are a number of very "clean" x-overs available at relatively modest cost, from Marchand and First Watt, to name just two. Two small amps can certainly outperform one large one, and for less money. The boutique parts for a speaker-level x/o are very expensive, and don't provide the improvement a well-implemented line-level x/o will. Paul Heath's advice is very old (I remember him from the 1970's), and very outdated.

 

RE: Why bi-amp Mags?, posted on July 21, 2017 at 11:35:44
E-Stat
Audiophile

Posts: 37555
Joined: May 12, 2000
Contributor
  Since: April 5, 2002
 Assuming you begin with a speaker that already contains a high quality crossover, there is indeed some added expense involved.

Generally speaking, upper frequency drivers don't require as much power. If you look at the division of wattage with many multi-way speakers you can see that. Also, I find it isolates potential clipping at the bottom (which I find less objectionable) from the rest of the range where such is more obvious.

Although it's not exactly the same scenario, I high pass the small Acoustats in my HT system and supplement them with powered subs. That allows the stats to avoid diaphragm "slap" and provides more headroom. Meanwhile, the stereo subs do their thing independently for the bottom two octaves.

Another advantage is ability to use pairs of stereo amps to vertically bi-amp a speaker. That provides a similar channel separation benefit that you find using mono amps in a full range driven system. I do believe, however, that it is better to match similar amps for upper driver duties (i.e. midrange/tweeter) to maintain coherency even if their power output is different.

 

RE: Why bi-amp Mags?, posted on July 21, 2017 at 12:17:44
Satie
Audiophile

Posts: 5426
Joined: July 6, 2002
 Your advice from Heath Audio is not on point and misses the main point.

The main issue addressed by biamping is decoupling the power supplies (and output stages) running bass from those running the mid and tweeter. Everything else is less significant.

The demands of producing low frequencies are provision of high currents over prolonged periods. The demands for higher frequencies are fast response, dynamic voltage/power (usually measured over 20 or 200ms) and lack of distortion. Providing these in a single amplifier is very expensive as the linear power supply will start to compress as it operates outside of the linear region up to 1/3 of its rated output much of the time while playing bass. To make full use of the power delivery of the supplies and save the largest cost in an amplifier, feedback is used liberally and often aggressively to linearise the power supply sag, which compromises transient/time domain performance.
Building one amp for the top end and one for the bottom end allows the top end amp to operate at the lower portion of the power supply's capacity most of the time or use the power supply and heat dissipation capacity to operate in class A most of the time, and allows the use of high feedback amps at low freq to save 70% of the transformer capacity - which reduces expense by a factor of 4.
Where some highly sensitive people have problems is in coherence between the two amps being used. That can be addressed by careful selection of amps to match each other and tuning of the crossover if that does not prove sufficient in removing obviously audible transitions from one amp's operation to the other's.

 

RE: Why bi-amp Mags?, posted on July 21, 2017 at 14:44:56
Davey
 LMAO at two PM's received from Steve. :)
Apparently it's his shtick to post silly messages on the forum and then attempt to engage in sillier off-line conversations.
This is a new troll routine I haven't seen before.
Ha!

Dave.

 

RE: Why bi-amp Mags?, posted on July 21, 2017 at 18:40:43
emailtim
Audiophile

Posts: 5373
Joined: July 2, 2017
 Here is some good information if you are serious about the topic you raise:

http://sound.whsites.net/bi-amp.htm
http://sound.whsites.net/bi-amp2.htm
http://sound.whsites.net/biamp-vs-passive.htm

Also, if you actively biamp vertically, you can get rid of the speaker cables by replacing them with short jumpers.
.

2022/03/30 Historical Records CENSORED

 

New to forum, posted on July 21, 2017 at 18:44:14
emailtim
Audiophile

Posts: 5373
Joined: July 2, 2017
 Looks like he is new to the forum (Date Registered: May 23, 2017).
.

2022/03/30 Historical Records CENSORED

 

RE: Why bi-amp Mags?, posted on July 21, 2017 at 19:22:50
JBen
Audiophile

Posts: 3082
Location: South FL
Joined: May 18, 2008
Contributor
  Since: July 26, 2010
 Steve, Satie just covered some of the bases very well. Emailtim also added useful links. Many of us who have navigated those waters enjoy music delights few folks can get at any price remotely resembling the price-to-value that can be obtained. Granted, it is often a DIY-driven effort. One which requires not so much money as dedication and some skills. But if I did it...

So, not that this is for everyone, but "expensive" it does not need be. In fact it can be EXTREMELY cost effective. And, in terms of customizing to your own needs, priceless.

In a few minutes my gear will be warm enough for a serious listen -- of some recent tweaks I now need to refine :). Still, my set of very cheap old MMG's are already shaking my seat here, 30+ft away. That's plain MMG's with no woofers or subs, mind you. Their bass is not just extended and strong...delicious instrumental textures are also retained. Their tweeters are delivering a cleanly extended, ribbon-like quality at the top end.

The music can be listened on for tens of continuous hours, in a 3D imaged -- often larger-than-room -- sound stage. And, if I were sitting in front of them, even "out-of-tune" as they still are, their dynamic slam would belie their being planar speakers...and laugh madly at being called MMG-like.

That's with no preamp at all, straight out of cheap class-A DAC, into a simple passive crossover network and into the power amps. Then, each tweeter and mid/bass panel gets its own dedicated juice, about 300w each. My cheapies I would not trade for many speakers at any price point.

In my case, purchased along time, the decent power amps were less that $700 in total. Furthermore, I only paid about $100 for the Teflon caps I now use in the PLLXO filter set. These are not mandatory, at all. In fact, initially, $30 bucks in good parts provided a superb duo of 1st/1st and a 1st/2nd order sloped two-way crossovers.

If you need more, passive filtering may not be enough. Luckily, active systems can be sweet too! And with the cheap super PC's and mini boards now available, there is a world of crossover filtering flexibility to provide all kinds of DSP goodies, for those who want it. No need to break the bank, just some smart purchasing, patience and proper advice, if needed.

On the later, for those with the serious interest, some decent folks here will provide guidance. This really comes in handy if you have, or plan to get, planars, more so if Maggies.

Darn, I may sound a little bit of an evangelist... Time for the music.


 

RE: New to forum, posted on July 21, 2017 at 19:57:25
steve.sukiennik
Audiophile

Posts: 206
Location: Chicago, IL USA
Joined: May 23, 2017
 Hi emailtim,
I greatly appreciate the detailed results of these X-over inprovements.
However nowhere does it address the crux of my point. Yes indeed biamping is better & much more sophisticated. Y isn't there any discussion supporting the reality that the very same amount of $ spent on a single more expensive amp generally or probably always sounds much much more clearer. How is it possible 4 2 dirty amps along w/a dirty electronic active X-over to become CLEARER than 1 single clearer amp. U's all must have never heard esoteric electronics. It's not personal choice. It's not as good. Lincolns R great but Caddies blow 'em away overall in the day of course.
Steve

 

RE: New to forum, posted on July 21, 2017 at 21:01:03
emailtim
Audiophile

Posts: 5373
Joined: July 2, 2017
 I think you are making an incorrect assumption that everyone that biamps uses crappy amps. They don't. You are also assuming that audiophiles don't spend money, they do (yes, some are frugal).

Don't knock it until you have personally tried it. You might be pleasantly surprised.

There are many here that technically know more about it than I do (read the 3 links provided for more information), but I have been doing it for years on 3.6's and 20.1's (cheap to expensive amps, both cheap and expensive being relative terms). The improvements are obvious if you use the correct points and slopes for your application. I have found vertical biamping to produce the best results.

As for your assumption that electronic crossovers are "dirty", please Davey's response. https://www.audioasylum.com/forums/MUG/messages/22/226611.html
.

2022/03/30 Historical Records CENSORED

 

RE a couple of your points, posted on July 22, 2017 at 02:41:22
JBen
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Location: South FL
Joined: May 18, 2008
Contributor
  Since: July 26, 2010
 RE:" How is it possible 4 2 dirty amps along w/a dirty electronic active X-over to become CLEARER than 1 single clearer amp."

Because you were told an incomplete story. So incomplete, in fact, that we would spend too much time explaining it. We can try, but you have to want to go there.
-- Among other things, the intrinsic math of what you are talking about actually offers a far wider range of possibility than what simple additions may suggest.
-- For example, the behavior of two similar amps used at closer to their optimal power ranges, may yield better music purity than a single amp driven harder.
-- Then, by powering their respective drivers DIRECTLY, multi-amping can gain a tremendous advantage in CLARITY, to say the least. A quasi-ribbon tweeter WILL scare some real ribbons crapless at times. Mid/bass panels WILL at times blow even some larger non-biamped Maggies off the map, if they are not careful. And those larger, properly multi-amped Maggies, WILL leave many "Esoteric" speakers drowned by their sonic wake. (LOL, watch out for those 3.6R and 20.1!) The same applies to other multi-amped planars and dipoles. You give'm half a proper chance and they shine bright and clear.
-- Furthermore, if you tweak for it, the driver-amp interaction can provide results to die for in terms of not just clarity but almost every other single desirable trait. You CANNOT do this with a speaker-level, single amp approach.
-- Besides, you don't even need an electronic (active) xover, which BTW, can still be FAR better than what speaker-level xovers can be.
-- This is because -- where a PLLXO can be used instead -- WOW! They are often confused for "active" but they are not... they are totally passive. They forgo the supporting electronics. Unfortunately, while unbeatable in the right usage context, they are not ideal in many situations.
-- In the end, the real and imagined issues can be dealt with. Well, almost always... if it were THAT easy, everyone would be doing this. :)
-- Importantly, it is not always advisable or desirable to pursue multi-amping.

Re: "U's all must have never heard esoteric electronics."

Many here actually have, and often. Better yet, several here also attend live concerts every now and then. Furthermore, some even grew up and/or worked in music performing environments. I happen to belong in all 3 groups. Which is why I understand this: One thing many of us have in common is that, although "esoteric systems" may impress, they do not easily cut it for us planar lovers.

There simply tends to be a closeness in experience to more of the real music with planars and with good dipoles in general. I just read in another thread that you may have owned Maggies, so I suspect that you agree.

So, your original question, "Why bi-amp Maggies?" could have a clear cut answer:
Because if you do it right, you will never stop loving the delightfully sounding BEAST that you have created." Release the Kraken!

 

RE: Why bi-amp Mags?, posted on July 22, 2017 at 07:24:53
steve.sukiennik
Audiophile

Posts: 206
Location: Chicago, IL USA
Joined: May 23, 2017
 Hay JBen,
Thank U, Thank U, Thank U,
Finally someone who can answer the question.
I fully realize all the other outcomes performances that U accurately relayed. I've had an electric X-over arrangement B4.
So if I spend $10k on a crystal clean amp used on an MG2 with it's one dirty choke & one dirty cap, will sound worse than spending $10k on 2 less expensive dirtier amps & one dirty electric X-overs? It's ($10k) vs ($4k + $4k + $2k) Yes or No?

Thx
Steve

 

"esoteric electronics" or "Esoteric" ?, posted on July 22, 2017 at 09:46:55
emailtim
Audiophile

Posts: 5373
Joined: July 2, 2017
 Does Steve mean "esoteric electronics" the generic term or "Esoteric" the specific audio company ?
.

2022/03/30 Historical Records CENSORED

 

RE: Why bi-amp Mags?, posted on July 22, 2017 at 13:29:35
JBen
Audiophile

Posts: 3082
Location: South FL
Joined: May 18, 2008
Contributor
  Since: July 26, 2010
 Thanks, Steve. At some point it would be good to learn your aims, likes and dislikes, and types of music preferred, to fine tune suggestions. I am ecclectic but heavily skewed towards classical, jazz and instrumental music in general. That said, last night I began with Bob James's "Hand Down", then Ritenour's "6 Strings Theory" cd. But soon it was voices, some rock and finally The Nitty Gritty Dirty Band's "Nine Pound Hammer".

To your question, I would like to say "yes". But unfortunately it is not that simple when we are talking of older speakers like ours. I was lucky, my old MMG's were made different from later MMG's. It meant that I would be able to invest tweaking effort & money, and the benefits would show through better. But, unless modded in other ways already, the MG2 may not justify such effort if you have a budget like that.

If I had that kind of money, I'd be looking at a whole world of other combos. This is even assuming that the MG2 were in mint condition. Right off the top of my head, I'd consider buying a 3.7i pair + a Sanders Magtech power amp. The 3.7i are not bi-ampable (factory :). But no bi-amping is required for a universe of musical goodness with this combo. (I've heard it beat $50k+ speakers driven by $120k in gear AND set by their own factory in a customized room). LOL, but never mind that I would still hack into them 3.7i and bi/tri amp at the next opportunity. It is mutated DNA in my head, I reckon.

OTH, it is not bad DNA to buy 3.6R and bi-amp with something like two Parasound A-21 or the like. THAT could be a mouth-watering, category-beating project (yeah, I am trying to talk myself into it also :). Even the stock 3.7i would have much to worry about. And if Magtechs or some of the other higher-end amps are thrown in...

My own system uses older Parasounds that are direct predecessors of the A-21. This is because all that lineup of the MOSFET-driven John Curl design, mix transparently among themselves. No worries. It makes life easier and sweeter, to say the least. They most certainly are not the only promising quality/value options, and folks here provide solid info on good alternatives to help you chose.

Now, say that I want to keep the MG2. If they are in good shape, there may STILL be mouth-watering performance opportunities. Let's see. A two-way design like that would probably love working with a PLLXO. The active xover may be not be needed at all, depending on other factors.

With the MG2, you won't have to worry much about the extreme top end. That is, unless someone added a QR or a ribbon tweeter to it and I missed the show. Therefore, you can take advantage of many more power amps out there. No need to worry about minor things which the speakers cannot deliver at the top. There's still plenty greatness left to be exploited.

In fact, with a a properly reinforced MG2 frame, I salivate at the thought of what some peppy Emotivas can do. But you DO have to reinforce the frame, that's key in any approach (even with no bi-amping). Some of these Emo's can really shake things via a properly tuned set of Maggies, and in high-end style. In fact, I suspect that some Emotiva monos could be perfect for the MG2...a ton of class A output available in the range the speaker can deliver. Well, that's just me, dreaming things up. :)


 

RE: "esoteric electronics" or "Esoteric" ?, posted on July 22, 2017 at 13:44:53
JBen
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Posts: 3082
Location: South FL
Joined: May 18, 2008
Contributor
  Since: July 26, 2010
 LOL, it should have crossed my mind but it did not. They qualify, anyway. To be fair, both times that their pricey gear was involved, it would not have been their fault that the system failed to impress me. It is amazing what some audio integrators can sell for such high prices and comparatively low performance.

 

RE: Why bi-amp Mags?, posted on July 22, 2017 at 13:53:11
steve.sukiennik
Audiophile

Posts: 206
Location: Chicago, IL USA
Joined: May 23, 2017
 Hay JBen,
Thanks. Delicious is the rite on description of what I need. I suffer greatly from dullness. Maybe Magnepan made the ones U'r talking about non-bi-ampable cause they know it can B $$ wasted. So is one(1) single balls out super spectacular amp the way 2 go. I had active X-over B4 & it all in all sucked.
Thx,
Steve

 

RE: Why bi-amp Mags?, posted on July 22, 2017 at 14:46:52
Satie
Audiophile

Posts: 5426
Joined: July 6, 2002
 As a practical matter biamping to achieve best results is much cheaper than obtaining them with single amping. Furthermore, biamping can provide amp performance that is not possible when using a single amp.

Optimizing the crossover on the speaker is part of it. The money sink there is the optimal capacitor for the high pass. You would want a foil cap or a high quality metalized cap bypassed with a foil cap. That would be $500-1000 depending on what you wanted.
The line level crossover for biamping can be very cheaply made with the critical high pass filter provided by the highest quality foil cap for well under $100 and if you are a cheapskate you can use a pair of <$1 foil caps and still get better results than provided by any amp driving the whole speaker with even a high grade high pass cap in it. For the low pass you can use a passive 1st (T-1D) or 2nd (MG2B) order which would be also just a handful of dollars to implement and will outdo anything you are likely to put into the speaker for low pass. For 3rd order (3.6 T-IV or IVA) you will need an active electronic low pass filter - you can build one or use one of the commercial ones, or have Marchand build one for you at high quality and with an exact copy of the electrical performance of the OEM crossover.

The large Ayre or similar amps that are optimal for a fully tweaked out maggie cost in the multiple 5 figures. You are paying to have headroom on the amp so that it is operating optimally in the mid and high frequencies where you are wanting clarity and linearity.

For biamping you can use a highly refined class A amp on top and even tubes and a high power high feedback bass amp that you would not necessarily want to ever hear driving your tweeter. Say a pro audio amp, or an Emotiva.
Another option that saves you tons of money is biamping with a multichannel amp as I suggested in another reply to you. As the best of them when bought on the used market are great bargains compared to two channel amps with similar power. Typical used prices for a discontinued model is 20% of the original price.

 

RE: Why bi-amp Mags?, posted on July 22, 2017 at 15:54:38
JBen
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Posts: 3082
Location: South FL
Joined: May 18, 2008
Contributor
  Since: July 26, 2010
 Steve, Magnepan, in the 3.7/i, put together really tangible improvements that showed with no need for an "imperfect" multi-amping option. It's like you got one of those original CTS-V Caddies and thought, "why would I add the unofficial computer performance tweaks, after all? This sucker is already top fun and will break my neck even now!"

That's kind of what 3.7i's can do, properly powered and located. Not "boring" at all once they break in for a few hundred hours. For me, they were the first Maggies to ever do planar-only slammy dynamics perhaps better than what I get at home, and do so in a dealer's setting, no mean feat! The same large room never helped the 20.1's do much for me. In addition, the 3.7 delivered there the 3D imaged sound stage that I can only achieve with PLLXO-based biamping at home and only after much tweaking. That was with the Magtech. Impressively, although with a very different presentation, they can still dance to the tune of less watts. Like less than 80wpc from McIntosh tubes. Not that I preferred it to Magtech's job, but it had great charm.

Then again, if I ever bought them...my mutant DNA would prevail :) There is upside potential left in the 3.7i if a proper line-level xover is used in bi/tri amp mode. Not easy but it could be done. It is what we mean. Properly matched, and crossed, even a $30 passive line-level xover and decent power amps can take Maggies further beyond factory performance. The beauty for you is that there may be no rush or even need to go there AT ALL...it is just potential.

 

Bi-amping on a budget, posted on July 22, 2017 at 15:58:50
Skeepowder
Audiophile

Posts: 57
Location: WA State
Joined: August 3, 2016
 It can be done easy and cheaply. Use a good quality multi channel amp. The Mac MC7106 and the Krell KAV500 both rock and I have both. They are only about a $1000 MOL. I am bi-amping my totally rebuilt MG111As with the factory crossover and it is pretty damn fine. And I'm using a Pioneer HT receiver for pre-amp. I like it.
Mac MC7106, Krell KAV-250a, Krell KAV-500, Maggie MG111, ADS 810 & 780, Pioneer SC-1522, Dahlquist 903, AR 1

 

RE: Why bi-amp Mags?, posted on July 22, 2017 at 17:14:38
BDP24
Audiophile

Posts: 1070
Location: Vancouver, Washington
Joined: September 12, 2013
 I hope Steve appreciates the level of generosity ya'll are showing him. He is obviously unaware of what he doesn't know, thinking he knows more than he actually does. He's way behind everyone else in this thread, but doesn't even know enough to realize it. Nothing personal Steve, but geez, you're embarrassing yourself.

 

3.7i, posted on July 22, 2017 at 19:38:59
emailtim
Audiophile

Posts: 5373
Joined: July 2, 2017

JBen,

What is different on the 3.7i over the 3.6's ? From what I have read:

- Flat wire instead of round wire on the Mylar.
- Series XO.
- Can't biamp.
- Super tweeter
- What ever the "i" adds
- Still has single plane of magnets, not dual plane like in the 20.x series.

Anything else ?
.

2022/03/30 Historical Records CENSORED

 

RE: 3.7i, posted on July 22, 2017 at 22:10:49
JBen
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Posts: 3082
Location: South FL
Joined: May 18, 2008
Contributor
  Since: July 26, 2010
 ETim, other than there being no "super tweeter" (AFAIK) your list is complete. A few comments (and opinions for which I will be sent to the Inquisition).

1. The genius is in the details and they orchestrated this 3.7/i baby very very well. I have always liked the 3.7/i when listened to anywhere, and even at its worst (green, right out of the box) it has charms.

2. With one single doubt, I am sure that a well-tweaked 3.6R with a line-level xover/multi-amping config and other mods could humble an UNMODDED 3.7i. The single doubt? I do not know if the superb ribbon/Mylar integration of the 3.7i could be matched.

OTOH, driving after an audition, remembering well-known musical passages, I keep having this nagging "feeling" that the darn 3.6R tweeters are sweeter-sounding and more extended. (I will burn at the stake for saying this.:) That said, it may just be a matter of tuning...

You hit the nail on the one-sided pole issue, which both share and the 20.x is not affected by. Since only a few people can get 20.x in their rooms, I'll just provide a positive. On the "lesser" Maggies, flip speaker polarity during some albums and get a nice improvement. At home, in the dedicated music PC, I configured Foobar2k to do this for me from my seat. Not earthshaking but it can be a pleasing option to recover better music from some recordings.

Anyway, one of these days I may snatch a set of 3.6R and start doing some surgery. I am in no rush and I fear that Magnepan's job with the 3.7i may not be beat on every single count. However, there's a ton of fun to be had in trying. OR...Perhaps you already did and are keeping it a secret? LOL








{Oh, BTW, please see if you can edit your post with a much smaller version of the schematics. On the PC monitor, it only distorts the thread view but in smaller devices it is murder.)

 

RE: Why bi-amp Mags?, posted on July 24, 2017 at 10:57:21
jimf42
Audiophile

Posts: 12
Joined: May 21, 2002
 I ran my MGIIIas for years with the XO-1 boxes and biamped with Bryston 3B amps. Definitely worked well.. I recently acquired a Bryston 10B electronic crossover and added it to the system. It makes a big difference and greatly improves bass performance.

I strongly recommend it.

 

RE: Why bi-amp Mags?, posted on July 24, 2017 at 14:24:32
emailtim
Audiophile

Posts: 5373
Joined: July 2, 2017
 So you bought one of those dirty Bryston electronic XO's ? =)

Did you get the STD or the SUB version ?
.

2022/03/30 Historical Records CENSORED

 

RE: Why bi-amp Mags?, posted on July 24, 2017 at 23:07:21
JBen
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Posts: 3082
Location: South FL
Joined: May 18, 2008
Contributor
  Since: July 26, 2010
 "So you bought one of those dirty Bryston electronic XO's ? =)"

LOL!!!

 

RE: Why bi-amp Mags?, posted on July 28, 2017 at 23:31:16
gracky
Audiophile

Posts: 20
Joined: October 15, 2014
 I'm bi-amping a mini maggie system (with a pair of DWMs for the in-room-configuration) with a Ayre V-5xe and a pair of Calyx mono 500 (ice module based class D, 500w/8ohm) and First Watt B4 active crossover (well, PSU modded). Ayre for the satellite panels and Calyx for DWMs. I believe this is a huge upgrade from the single Ayre driving the whole system, and doubt if any single stereo (or mono pair) of same price to Ayre + Calyx + B4 could achieve this performance. Another benefit of bi-amping was I could lift up the woofers to the height of my ears reducing the distance between panels while keeping the tonal balance of bass. It was impossible with default passive crossover supposedly because of dipole cancellation.

 

RE: Why bi-amp Mags?, posted on July 28, 2017 at 23:41:55
gracky
Audiophile

Posts: 20
Joined: October 15, 2014
 Why not 3.7? The room is too small for 3.7, with width of only 11' 9". My former room was yet smaller (and big Maggies are hard to import to this country :( ). In some situation, bi-amping can be the best way to improve sound.

 

Twin DWMs, posted on July 29, 2017 at 20:07:51
emailtim
Audiophile

Posts: 5373
Joined: July 2, 2017

Gracky,

How did you wire the dual voice coils in the DWMs (series, parallel, just use 1 side) with the mono-block amps ?
.

2022/03/30 Historical Records CENSORED

 

RE: Twin DWMs, posted on July 29, 2017 at 23:22:34
gracky
Audiophile

Posts: 20
Joined: October 15, 2014



Like the picture, 2 voice coils in series bypassing the internal xo I suppose.
I've not un-soxed the dwms but looking at closely some available pictures of dwms and proving the terminals with a multimeter, I think this wiring bypasses the xo. But of course I can't give any guarantee.
Why I did series wiring is the amp. The total impedance is 8 ohm and it makes an easier load for the class D amp.

 

RE: Twin DWMs, posted on July 30, 2017 at 11:32:43
emailtim
Audiophile

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Joined: July 2, 2017

Interesting hookup. You can always remove the 4 screws (minimally invasive if you haven't already tried it) from the mounting plate and check the internal wiring.
.

2022/03/30 Historical Records CENSORED

 

RE: Why bi-amp Mags?, posted on July 31, 2017 at 16:05:33
steve.sukiennik
Audiophile

Posts: 206
Location: Chicago, IL USA
Joined: May 23, 2017
 Hay JBen,
I do have T-1D's & 1 Quad 606 amp. I gotta get it rite the very 1st time. I don't wanna get a good X-over if I can get a GREAT 1 4 a little more. Not the best but the (absolute best 4 the absolute least) approach. The valley graph line where the euphoria border bends down ALOTTTTTT. U get it.
U'r help is very appreciated. I can build if nec. What shood I get?
Thx,
Steve

 

RE: Why bi-amp Mags?, posted on July 31, 2017 at 23:56:38
JBen
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Contributor
  Since: July 26, 2010
 Steve, I don't have experience with that model but I suspect that no one can honestly offer a one-tweak-fits-all solution. Besides, you know how interactive the darn speakers are to their respective surroundings. You actually have to tweak things relative to this. So, it can be FUN, but not in a manner that would "get it rite the very 1st time".

Luckily, it is relatively easy and even initial results could WOW you (and far more so if you make sure that the speaker frames have been reinforced.) Your speakers may have come with a 1st order or perhaps 1st/2nd order xovers. If so, a PLLXO (passive line-level xover) could offer unbeatable performance and value.


I wish I had the time to research the specifics for your case. Happily, there are more folks with more experience than I have here. Among them, Neolith once put together a valuable spreadsheet that lists the original xover slopes. It also offers other useful goodies. See if you can get it (I misplaced my copy) and look for your model's specific values.

Then we would need specs for two stereo power amps that you will need. You mentioned that you only have one. Well, perhaps you have another and don't know it? Here is the thing. That extra stereo amp does not need to be "special" or the final one. For the development phase, it can even be 2 spare channels from a receiver that you may already have. So, dig around and make an inventory of the hardware you already have.

So, we find factory-original values for the speaker xovers and impedance/power values for the amps. We then use these figures to try and replicate the same xover slopes that your speaker came with. This is executed with cheap parts for a trial set. Parts may cost you <$20. Later on you can upgrade them, if need be.

That's it, in a nutshell. A PLLXO-based biamp offers magic, is inexpensive and can be put together easily. AND, if the frames of the speakers are strong enough or are reinforced, the clarity brought by the biamp is not muddled by flimsily vibrating frames.




 

RE: Why bi-amp Mags?, posted on August 1, 2017 at 06:16:45
steve.sukiennik
Audiophile

Posts: 206
Location: Chicago, IL USA
Joined: May 23, 2017
 Hay JBen,
Thanks millions 4 getting me on the rite road. I totally know & fully understand the importance of solidifying the panel frames. Just think, when the diaphragm pushes forward then so does the frame, net effect: cancelled wave. Also in tymps, my experience is 2 NEVER fold any panels as the orig'l manual suggests. Again think of it: the waves R against each other instead of both pumping 2gether in even unison.
Back to the PLLXO, Yes U RRRRR leading me 2 the final XO. All makes sense w/the component match up which I am absorbing, tho slowly. It shoodn't B long. I'm 4 courses short of an EE & my writing is very simple & digital machine-like but I'm not a dumb dumb.
Thx,
Steve

 

RE: Why bi-amp Mags?, posted on August 2, 2017 at 00:36:19
JBen
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  Since: July 26, 2010
 Steve, slow is just fine; it's still relatively fast, if Einstein is to be believed :)

I forgot to mention that we also need to have the impedance of each driver. You may already have this information or you can measure them. I could not find a schematic of the xover but did find the [nominal] xover frequency.

I also found that it is a 1st order xover. While things are never as easy as one wishes, this should make things easier...and better...and cheaper.



 

RE: Why bi-amp Mags?, posted on August 2, 2017 at 06:10:03
jimf42
Audiophile

Posts: 12
Joined: May 21, 2002
 I bought the std, not the sub. The 10B has just had a full Bryston factory overhaul. The improvement in performance from using the factory xovers was not subtle. It was immediately noticeable, even though I am still tweaking the settings bit to see if there is further improvement to be had.

Since i already had two Bryston 3Bs, I did not see the need to get a multichannel amp...although that too was a good idea.

 

RE: Why bi-amp Mags?, posted on August 2, 2017 at 06:47:00
steve.sukiennik
Audiophile

Posts: 206
Location: Chicago, IL USA
Joined: May 23, 2017
 Hay JBen358,
Yes indeed, U R helping me get 2 the final arrangement. As U mite C from my equip list that I generally buy 4 the long haul, avoiding obsolescence wen at all possible. I'll follow thru w/the details U outlined & get my T-1D's biamped the rite way, tho not rite a way. Euphoric fun, fun, fun, Biff, Bam, Pow Batman.
Thx,
Steve

 

RE: Why bi-amp Mags?, posted on August 2, 2017 at 09:58:44
Satie
Audiophile

Posts: 5426
Joined: July 6, 2002
 That is something I was trying to convey to Steve, that the "dirty" components are the industry standard high value caps and inductors, particularly the 3rd order bass low pass or in his case the inductor for the 1st order low pass. The other thing being the complex load of the 3rd (or 4th) order XO affecting the bass amp or the single amp for the integrated speaker, which reduces its performance.

 

RE: Why bi-amp Mags?, posted on August 2, 2017 at 17:33:58
BDP24
Audiophile

Posts: 1070
Location: Vancouver, Washington
Joined: September 12, 2013
 For a speaker like the Tympani-I or -4 (but not 4a), which requires just a 1st order, 6dB/octave high pass filter, all that's required, as Satie has said many times, is only a single capacitor, installed on the input jacks of the power amp feeding the m/t panels. This method avoids active electronics, as well as another inter-connect cable. For the 3rd order low pass leg (required by the Tympani-IV), a simple, inexpensive active x/o will be fine, like the old Dahlquist DQ-LP1. There is no reason it has to be a "dirty" one ;-).

 

RE: Why bi-amp Mags?, posted on August 3, 2017 at 14:38:12
BDP24
Audiophile

Posts: 1070
Location: Vancouver, Washington
Joined: September 12, 2013
 Speaking of Tympani's and crossovers, both the T-IV and T-IVa have a 3rd order low pass at 250HZ, but the high pass are different, the T-IV a 1st order at 500Hz, the T-IVa a 2nd order at 400Hz. If I want to use a 1st order high pass on the T-IVa, will reversing the polarity on the m/t panels (or flipping them front to back) put things back in phase, all else being the same?

 

RE: Why bi-amp Mags?, posted on August 3, 2017 at 15:27:00
JBen
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Contributor
  Since: July 26, 2010
 JBen358?? Hey, Steve, Josh is going to be mighty insulted if you misplaced those numbers. LOL

 

RE: Why bi-amp Mags?, posted on August 3, 2017 at 15:57:08
steve.sukiennik
Audiophile

Posts: 206
Location: Chicago, IL USA
Joined: May 23, 2017
 Hay JBen358,
Sorry, I back tracked & I'm lost at NUMBERS? Maybe U can refresh.
Steve

 

RE: Why bi-amp Mags?, posted on August 3, 2017 at 19:23:02
JBen
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Contributor
  Since: July 26, 2010
 I mean that the "358" is part of Josh's moniker (Josh358)...not mine :))

 

RE: Why bi-amp Mags?, posted on August 3, 2017 at 22:34:24
Roger Gustavsson
Audiophile

Posts: 2054
Location: Huskvarna
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 BDP24 wrote:

"Speaking of Tympani's and crossovers, both the T-IV and T-IVa have a 3rd order low pass at 250HZ, but the high pass are different, the T-IV a 1st order at 500Hz, the T-IVa a 2nd order at 400Hz. If I want to use a 1st order high pass on the T-IVa, will reversing the polarity on the m/t panels (or flipping them front to back) put things back in phase, all else being the same?"

Yes, reversing the polarity is the way to go. Not sure but maybe you should try a different crossover frequency too?

 

RE: Why bi-amp Mags?, posted on August 3, 2017 at 23:59:42
BDP24
Audiophile

Posts: 1070
Location: Vancouver, Washington
Joined: September 12, 2013
 Thanks Roger. No reason not to try the T-IV's 500Hz on the T-IVa, I suppose. I should look at the internal x/o parts values (if there are any) in both speakers to see if they are different. Beside the mid panel to ribbon tweeter x/o, of course. That will remain stock, I'm not tri-amping.

 

RE: Why bi-amp Mags?, posted on August 4, 2017 at 01:45:40
Roger Gustavsson
Audiophile

Posts: 2054
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 The IV and IVa have different crossovers. You should look at the outboard crossovers not the internal crossover that only do the mid-to-tweeter.

http://www.integracoustics.com/MUG/MUG/tweaks/mikebarney/Tympani-4s_xo.pdf

 

RE: Why bi-amp Mags?, posted on August 4, 2017 at 01:55:32
BDP24
Audiophile

Posts: 1070
Location: Vancouver, Washington
Joined: September 12, 2013
 Oh yeah, thanks for reminding me Roger. Only the mid-to-tweeter x/o is internal, the outboard boxes do ALL the bass to mid filtering, and that is textbook 3rd order low pass and 2nd order high pass. That simplifies things! Actually, I won't be using them at all, as I will be bi-amping with a First Watt B4 doing the filtering.

 

RE: Why bi-amp Mags?, posted on August 4, 2017 at 02:07:20
steve.sukiennik
Audiophile

Posts: 206
Location: Chicago, IL USA
Joined: May 23, 2017
 Hay JBen,
Got my 1st letter (J) mixed up in my mixed up head. No offense, nothing personal. Sorry
Besides I haven't rec'd much info on [? Equip 2 run Mags in Van/SUV]. Guess it's break week. No problem.
Thx,
Steve

 

RE: Why bi-amp Mags?, posted on August 4, 2017 at 02:08:16
Roger Gustavsson
Audiophile

Posts: 2054
Location: Huskvarna
Joined: February 12, 2010
 Yes, that seems to be a good solution. I think the B4 is a bit too good for that task. With all its possibilities it deserves to be inserted even on the high pass filtering of the mids. You are not willing to sell the B4?

 

RE: Why bi-amp Mags?, posted on August 4, 2017 at 14:59:44
BDP24
Audiophile

Posts: 1070
Location: Vancouver, Washington
Joined: September 12, 2013
 Hmm, I don't know Roger. I bought it for filtering on all my bi-amped speakers---the ET LFT-8b's (1st order high and low at 175Hz), Quads (1st order at 75 or 100Hz), and the Tympanis (low pass 3rd @ 250Hz, hp 2nd @ 400Hz on the T-IVa's, 1st @ 500Hz on the T-IV's). That's one great thing about the B4---it's versatility. 1st, 2nd, 3rd, and 4th order, in 25Hz increments from 25Hz to 3200Hz! I'll ponder it.

 

RE: Why bi-amp Mags?, posted on August 5, 2017 at 15:15:40
Satie
Audiophile

Posts: 5426
Joined: July 6, 2002
 The IVa has more extension than the IV mids but is no better on power handling at those lower frequencies, hence the 2nd order IVA vs 1st order IV and 400hz vs 500hz. If you want to go 1st order on the IVA you can use the 500hz high pass, or - if you trust yourself not to pound the speaker into the ground with loud music then you can probably take the high pass to 1st order 400hz. Of course, yo will have to use the matching low pass filter.

The IVa with IV crossover is one option.

TIVa with 1st order HP @400hz you will probably want to set your B4 one notch lower on the TIV crossover values rather than use the IVa values for the low pass.

 

RE: Why bi-amp Mags?, posted on August 5, 2017 at 15:18:53
watts
Audiophile

Posts: 536
Location: B.C.
Joined: June 30, 2004
 I just caught this post and finished reading this thread and am really surprised how long it is! I commend all of you for your patience! I am still trying to figure out how dirty my system is...

 

RE: Why bi-amp Mags?, posted on August 6, 2017 at 17:44:14
BDP24
Audiophile

Posts: 1070
Location: Vancouver, Washington
Joined: September 12, 2013
 I am confused (nothing new there!) by some of your statements, Satie. Could I impose on you for clarification?

- "you will have to use the matching low pass filter". What do you mean by matching?

- "you will probably want to set your B4 one notch lower on the TIV crossover values rather than use the IVa values for the low pass". By one notch lower do you mean in frequency, as in 225Hz rather than 250? Or in slope, as in 2nd order rather than 3rd? The TIV and TIVa share the same 250Hz/3rd order low pass, so I'm not following you.

As for using the TIV x/o boxes with the TIVa's, if I wasn't bi-amping the a's I might have to, as they came with only some of the case parts of their x/o's, and no guts. I didn't care, as I intended to bi-amp them anyway. But in any case it's academic, as I will be selling the TIV's, and their x/o boxes will go with them, of course.

As always, thanks!---Eric.

 

RE: Why bi-amp Mags?, posted on August 7, 2017 at 05:57:26
Roger Gustavsson
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 The schematics http://www.integracoustics.com/MUG/MUG/tweaks/mikebarney/Tympani-4s_xo.pdf shows a second order (12dB/octave) low pass on the IV and a third order (18dB/octave) low pass on the IVa.

 

RE: Why bi-amp Mags?, posted on August 7, 2017 at 06:43:36
BDP24
Audiophile

Posts: 1070
Location: Vancouver, Washington
Joined: September 12, 2013
 On the specs page of the owners manuals for both my T-IV and T-IVa, the low pass is specified as 3rd order Butterworth (18dB/octave) at 250Hz. The high pass for the m/t panels is 1st order (6dB) at 500Hz for the T-IV, and 2nd order (12dB) at 400Hz for the T-IVa. Are my manuals incorrect, or is the MUG schematic?

 

RE: Why bi-amp Mags?, posted on August 7, 2017 at 12:47:03
Roger Gustavsson
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 There is only a coil (6mH) and a capacitor (50uF) in the low pass section of the Tympani IV. That is 12 dB/octave.

 

RE: Why bi-amp Mags?, posted on August 7, 2017 at 12:52:29
BDP24
Audiophile

Posts: 1070
Location: Vancouver, Washington
Joined: September 12, 2013
 Well, thanks for the correct info Roger. Am I alone in finding it bewildering that Magnepan would cite incorrect information about their own product in it's owners manual?!

 

RE: Why bi-amp Mags?, posted on August 7, 2017 at 13:44:11
BDP24
Audiophile

Posts: 1070
Location: Vancouver, Washington
Joined: September 12, 2013
 I just looked at the T-IV and T-IVa schematics on the Integracoustics/MUG site, and though both have 3rd order-18dB/octave listed for the low pass, the crossover values shown are different between the two. The T-IVa shows a pair of 2.05 mH coils, then a 200uF capacitor, then a 1.3 mH coil. The T-IV shows a pair of 3mH coils followed by a 50uF capacitor, exactly as Roger stated.

Who drew up those schematics? I put in a call to Magnepan, and a recording said they currently have no customer service representative!

 

RE: Why bi-amp Mags?, posted on August 8, 2017 at 08:12:36
jimf42
Audiophile

Posts: 12
Joined: May 21, 2002
 time for a system cleaning...

 

RE: Why bi-amp Mags?, posted on August 8, 2017 at 08:14:21
jimf42
Audiophile

Posts: 12
Joined: May 21, 2002
 I did not have much luck with Magnepan customer service when I had questions re the crossover frequencies... but there is also a thread on AudioCircles Planar Circle on the topic I found helpful.

 

RE: Why bi-amp Mags?, posted on August 8, 2017 at 08:53:56
Satie
Audiophile

Posts: 5426
Joined: July 6, 2002
 Change in Freq rather than slope.

I tried the TIV with 2nd order LP, 3rd (Butterworth) and 4th (LR) It is quite obvious that the 3rd LP and 1st HP is the better match for the speaker - both with Neo8 and stock. 2nd and 2nd symmetrical also works rather well.

.I was talking about setting your B4 for similar points to the TIV rather than the stock equivalent settings of the IVa as an option.

 

RE: Why bi-amp Mags?, posted on August 8, 2017 at 08:56:47
Roger Gustavsson
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Location: Huskvarna
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 I have some simulations using the values of the schematics. Could not post them as AudioAsylum was down. I will try tomorrow (saved it at my pc at work). I can tell they do look different!

 

RE: Why bi-amp Mags?, posted on August 8, 2017 at 08:59:35
Satie
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 I am not sure but if I remember correctly when I opened the XO boxes for my TIV over a decade ago it was 3rd order 2 inductors and a cap in between (at least appears to be)..

 

RE: Why bi-amp Mags?, posted on August 8, 2017 at 09:02:12
Satie
Audiophile

Posts: 5426
Joined: July 6, 2002
 Hang on to your B4 like a life raft.

 

RE: Why bi-amp Mags?, posted on August 8, 2017 at 09:16:21
Roger Gustavsson
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Posts: 2054
Location: Huskvarna
Joined: February 12, 2010
 Magnepan seems to change things during production. The TIV schematic found in the "tweaks" section refers to a serial number.

 

RE: Why bi-amp Mags?, posted on August 8, 2017 at 17:24:31
BDP24
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Posts: 1070
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 Satie, I read somewhere that the B4 was being discontinued, but it's still on their website. There's a Pass x/o on Audiogon right now, but at an asking price of almost $3k. I don't want one THAT much! Would be nice, though, as it runs balanced with XLR's.

 

RE: Why bi-amp Mags?, posted on August 9, 2017 at 08:44:38
Roger Gustavsson
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Posts: 2054
Location: Huskvarna
Joined: February 12, 2010

Simulated crossover electrical curves using the schematics in the "tweaks" section for T-IV and T-IVa.

 

RE: Why bi-amp Mags?, posted on August 9, 2017 at 08:56:37
Roger Gustavsson
Audiophile

Posts: 2054
Location: Huskvarna
Joined: February 12, 2010
 Simulated electrical crossover curves using the schematics in the "tweaks" section for T-IV and T-IVa.




 

RE: Why bi-amp Mags?, posted on August 9, 2017 at 10:46:28
Satie
Audiophile

Posts: 5426
Joined: July 6, 2002
 That is a real high end crossover with sufficient output to drive any amp and lots of gain if you need it.

 

RE: Why bi-amp Mags?, posted on August 9, 2017 at 14:00:20
BDP24
Audiophile

Posts: 1070
Location: Vancouver, Washington
Joined: September 12, 2013
 Thanks for the curves Roger---Eric.

 

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