Anthem D2/D2v/AVM50/AVM50v/ARC1 tweaking guide - Page 1207

That's why I always say your ears should have the final say and not the charts. If you are liking what you are hearing now, then I would say that your job is done regardless of how your charts look.

Enjoy!!!!

It is still something ARC is not doing and not helping with. Subwoofer phase/polarity is not the same as subwoofer distance so your "or" should actually be replaced with "and"), both of them can be used for speaker phase alignment. Although in my case I got much better results with just varying the subwoofer distance as it is not applying any kind of filters at the crossover point (phase/polarity), just delaying the signal (distance).

The problem with hearing is that it is subjective. It may initially like the wrong sound and dislike the right one but after some time it may like the right one even better. So it is always better to set everything right with some calibrated tools and ask you ears in a month if you like it.

All valid points guys. Agree sound is subjective and what my perceptions of great bass may be completely different to some of you. I know my current room isn't perfect but Im trying to get the best result with what I have to work with.

After setting volume on both subs using spl meter ARC set the final trim to +4.5. I found this odd as the meter was reading approx 72-73db for each ( they were done separately). Should I leave as is or adjust subs with spl again so ARC gets the trim closer to "0".? Is +4.5 too much of an adjustment for ARC to make. Clearly I set the subs volume nob on each too low despite what my analogue meter was showing. I use a proper tripod and connect spl to it and it's set to slow and C weight. It was calibrated about 3 years ago by Macca who posts here . Last calibration I got it to +.5 so I must have misread the meter.

Sound is waves in air and for low frequencies they are pretty long. And the length of wave is (speed of sound)/(frequency). For example, for 80Hz, the length of sound wave is 340.29 m/s divided by 80 Hz is 4.25 m (1126 ft/s divided by 80Hz is 14 feet). So for 80Hz you should try adjusting subwoofer frequency from minus 7 to plus 7 feet to cover the entire wave length. If two waves meet, they produce the new wave but the rusulting value can be anything from -2*amplitude to 2*amplitude (and zero is also in this range).
You can find a lot of information in the Internet, for example this is an excellent explanation with demos:
http://www.acoustics.salford.ac.uk/f...aves/super.htm


You are right, ARC won't show any difference as it is measuring the individual speakers and not pairs. But it is a different picture if you have more than one subwoofer.


No, the difference is huge. You can get anything from zero (when phases of main speakers and subwoofer are at 180 degrees from each other thus cancelling altogether) to 2*what_you_should_have. But it is mostly obvious in a crossover points where speakers are trying to blend in. For example, if your crossover point for mains is 80hz, then phase should be aligned at 80Hz. SPL meter is more than enough to do the alignment but calibrated microphone is a much better tool and you can actually see the resulting response curve not for individual speakers (like in ARC) but for different sets of speakers (left+sub, right+sub, center+sub, left+right+sub etc).

Highest reading will not be the best in most cases. When playing the test tone of your crossover frequency (and in its vicinity) through your left and sub (or right and sub), your SPL meter should register something close to 75 Db + your room gain set by ARC (I recommend HOLMImpulse for it). But the problem is the delta can be up to 1-2 Db so it is really easier to see thing in graph if you have calibrated microphone. So if crossover frequency for your main speakers is 80Hz, you should play 80Hz plus minus 10-20Hz and choose subwofer distance and phase so that that range would sound as close to 75Db + room gain as it is possible (but you have to make sure you set your sound level so that your higher frequencies not affected by room gain would be at 75 Db).


Please start with subwoofer distance first (plus minus 6-7 feet), phase applies some filter at a crossover point which complicates things. And you don't have to rerun ARC after you find a sweet spot. By the way, if you set the same crossover frequency for your mains and center, it may help a bit as it will be easier to align phases (for example if you have 65Hz and 70Hz, just choose 70Hz for both). Also, you can try to shift your cutoff frequency up or down in ARC software and choose the one which gives the smoothest graph possible, especially at the crossover point.

You should listen to what you have for a while to see how it sounds to you. If you run ARC again, I think you should turn up your sub a notch or two so ARC can set the trim, for your sub, closer to 0. BTW, ARC setting your sub's trim to +4.5 is not out of the norm; but, for me, I try to keep all of my speaker trims +/-3. Currently, all of my speaker trims are +/-1 with my sub's trim being set to +0.0.

Yep normally that's what I strive to get. All my other speakers are .5 to 1. I prefer the sub trim to be close to zero as possible like yourself. I tested a Bluray (Thor) and the bass sounded great, nice and deep room filling. I will redo it so the trims are closer to zero for the subs.

I remember reading years ago when I got into HT that we should try eliminate the receiver/processors calibration software from doing large corrections as it adds distortion. Is this the reason why we strive to get the trims as close to zero as possible for the subs?

Now that I think about it, you're right - like you, the only source I have without an HDMI output is actually my Pioneer Elite Laserdisc CLD-97 - what model do you have (just curious)? So I wasn't thinking, other than the laserdisc I'd be feeding HDMI to the Anthem.

My display is a rear-projection Toshiba 65HX81.

A quick search didn't turn up any US distributors for the HDfury3 - and honestly not sure about shelling out $400 directly to HDfury, when I'm probably close to buying a new display anyway. There's some much less expensive devices around that do the conversion - Monoprice has one for $40, and there's this one on Amazon that looks pretty good - but not sure how they compare.

- Mark

1. Oh yes ... if you have 2 or more subs, i have two subwoofers and phase matching them manually produces the best sub frequency response in my room, this assumes you've placed them at positions that are optimal as best you can. By best, i mean the widest possible and most even response before ARC. You do not want to have huge peaks and nulls in your response curve using "Quick Measure" as the test tool. After you've amplitude and phase match them, then let ARC do the rest. You'll get the best SW response curve your subs are able to produce in your room than you would w/o phase matching them.

In my room , i have one sub in front and the other behind me and its the best combination for me to get the most even bass as i movee about the room (YMMV).

2. The effects of phase matcing the subs to the room and then to the mains is not subtle but very audible. You may refer to my sig for further details on phase matching, if interested.

3. As i said before, i phase match the subs to the room before ARC. Afterwards, i run ARC then match the subs to the mains (around ARC's xover frequency) by varying the speaker distance. In my case, the results are worth it. The bass is not intrusive and doesn't call attention to itself. You get a seamless transition between your mains and subs that you do not notice where the mains end and the sub starts! Worth it indeed IMO

I hope I'm not boring others here with ARC charts, but here are the most recent ones with subs back to normal positions give or take a few feet. I have sent the results to a guy (HAA certified) that works for Acoustic Vision and he will advise what Bass Traps would suit my room and help improve the bass response.

I wont bother redoing ARC to get the subs trim lower than +4.5 as I will wait until I purchase the traps and then redo ARC.

Thanks for the input dkojevnikov and dmusoke.

dmusoke-- I reread your null/peak post and decided to apply it to my system.
Since I have only one sub I fortunatly didn't have to match subs to each other first.

I decided to use the null procedure, but I cheated a little, so please let me know if this is OK since my whole measurement depends on it. Since I have my front speakers bi-wired to the posts with spades (no banana plugs) reversing the wiring is a pita, so I went into the D2 setup menu-Speaker Configuration- and inverted the polarity on the sub during the test. Since the idea is to reverse the relative polarity between the LF and sub I didn't think it should matter where its done.

Assuming thats OK, I then put in a test cd I have that can be set to play specific freqencies. Since my crossovers are set to 60hz for fronts and center in my D2 setup 3a/b (not the cutoffs in ARC) I then played the 60hz track while adjusting the sub distance in the Listener Position section of setup.
The actual distance is @9.5 ft on a tape measure, but the lowest null reading came in at 18.5 ft. I don't know if its a coincidence that its approximately 2x the actual measurement or if its due to my room dimensions (10.5 ft wide x 17 ft deep) or the wave length of 60 hz, or what, but that was definitly the distance that got the lowest reading on my SPL meter. So thats the subwoofer distance I input into the D2 setup menu.

I then went back into 3a/b and set the sub polarity back to normal.

Bass seems fuller, but not boomy. Can't guarantee that its not placebo effect. Its not a huge difference to me, but definitly seems improved to my ears.

Tom

It seems to me that reverting the polarity for sub is OK for the null procedure. 18.5 ft is very close to the length of the 60Hz wave, 9.5 ft being close to a half of the 60Hz wavelength so your observations coincide with the physics of this world. I am curious what is the distance to your main speakers? Is the difference between (distance_to_main_speaker) - (distance_to_subwoofer) close to 9.5 ft? And where your subwoofer is located in reference to main speakers and your main seating point?

In my case the maximum was not the best settings as I had very huge bump at my crossover point with this setting. So I had to vary the distance until I found the smoothest response curve possible. It was actally less than physical distance to subwoofer. It may seem strange at first that the best setting is not a physical distance but you have to remember that your subwoofer is probably using the different amplifier than your main speakers and the speaker of subwoofer is much heavier thus there could be significant delays in wave impulse between main speakers and subwoofer. That's why it is more often called logical distance, not physical distance.

The subwoofer, an SVS SB13plus, is against the front wall in the corner 1' to the right of and behid the RF speaker. About 3'' fron the side wall and 15'' from the front wall. This is the optimal, practical position as found using QM in ARC.
The distance from my seat is 8.5' to RF and 9.5' to the sub.
The fronts are Paradigm S2's. They are 3' from backwall, 2.5' from the side walls and raised on stands that place the tweeters at ear-level. They were positioned for the best stereo imaging.
The center, C3, is on a shelf under my plasma centered between the fronts.

I have posted my most recent ARC music graph an targets.

Tom

Sorry I thought the Anthem "phase" was just an absolute phase adjustment not something funky like that! It actually had no effect for me until 180 degrees, the same as flipping polarity, so I don't use it.

I used quick measure to find the best place for the sub and would rather not move any speakers around. So I will have to be careful fiddling with the crossover points to get smooth interactions. Why fiddle? Because I noticed that ARC tends to give up and just cutoff problematic areas rather than try to EQ them.

Do you guys know if the LFE filter is applied to all bass in the sub channel including redirected bass or just the LFE channel?

I have the lowly CLD-59, wish I had the 97!

I dunno about those cheaper devices. They are probably very limited in bandwidth and what kind of support do they come with? The Fury line has taken a long time to get where they are and each generation has better picture quality and support, more stable firmware, less bugs, etc.

If you're not planning on keeping your set long then see if they'll sell you a HDF2. It will suit your needs, won't cost much, and help you sell that big ol' set.

Tom:

First of all, congrats on a successful phase cailibration. Its worth the effort indeed. Yes, you can reverse the sub polarity as you indicated or you can reverse the wires at the back end of your AVR /Power amplifier as well.

The null of 18.5 feet is right on. The actual value should be 18.77ft but ARC only does 0.5ft increments. The speed of sound is 1126 ft/sec (at 20 degrees Celcius), so at 60Hz, the first null is 1,126/60 = 18.77ft. You'll find other nulls at multiples of this distance of 18.77ft for ever (well, within reason for this calculated sub distance could be outside your own house and into the streets ).

Well couldn't wait as that +4.5 sub trim was annoying me. I redid ARC after turning each sub up one notch and ARC set it to 0 . Other channels are:

LF:0, RF:0.5, C:0.5, SL:0.5, SR:0.5.

Pretty happy with the sub trim now. Got too late to test the system so will have a listen tomorrow night.

I actually don't know what kind of filter Anthem is using for phase adjustment, it is their secret but by looking at response curve, the result of changing the phase and distance looked different. I could not achieve results similar to varying distance with varying the phase.

These secrets are revealed by searching for "all-pass filter". It is the standard phase control, delaying the signal by an amount that depends on frequency.

Polarity inversion is different and very often confused with the above in the case of 180 degree shift. Inversion makes the driver go in instead of out and out instead of in, with no delay.

Time alignment is also different. It delays the signal with no other alteration to it.

I got lucky on eBay...


OK, that all makes sense


Makes sense too, I may try that route.

Thanks.

- Mak

Thanks.

I have a bi-polar sub so my results may be atypical.

Do you guys get a pop from your speakers when turning OFF the AVM/D2?

Yes, but it may be my amplifier or amplifier + processor together.

No. My amps are enabled by D2v triggers and presumably go into standby before the D2v itself completes its power down.
-Bob

I get a slight pop sound when the Krell amp is on and the D2v turns off during the ARC calibration. But under normal conditions I've been told it's advisable to turn on the power amp/Subs after everything else is turned on (D2v,Bluray player,Projector). Then turn off Power amp/subs first when your finished using the system.

I think it is the AVM sending a small spike when it goes down - just minor annoyance, but not something I would expect at this snacking level.

Obviously using triggers would be better, but some people like to keep their amps on (warmed) at all times.

I don't think it would be all that hard for Anthem to fix do you?

That is indeed so.

Ever wondered by your incandescent light bulbs always tend to blow when you switch on or off, seldom while it's on? Same thing. As any electrical hobbyist can tell you, the switching process causes a spark at the switch or relay poles. This spark is a voltage spike which goes down the setup chain and gets amplified by the amp, hence the "pop". Its also the reason why switching contact points always get charred after some use.

This spark is usually largely absorbed by a filter circuit at the switch poles and power supply filter circuits, but sometimes, depending on design quality, there is a small leakage, so a small "pop". A big "pop" can burn your precious tweeters, as I have learnt from bitter experience.

The recommended procedure in powering down your equipment is to switch off your power amps first, then the pre and finally the sources. The reverse is true for switching on. Guaranteed no "pop".

Well, I for one did and found that it's not all that analogous to switching ordinary audio equipment on and off beyond the cringe factor. Perhaps it causes worry because it sends something to the senses, i.e. sound or a flash of light then darkness, but virtually all electrical equipment can be subjected to surges.

In school I learned that the tungsten filament in an incandescent bulb must be run as hot as possible for most efficient light output. There is also the matter of how cheaply bulbs are made and if enough money was spent on it a filament that lasts a lifetime can be had. Household bulbs are intended to be cheap and replaceable which is why they use sockets. Later, as a tube amp hobbyist and technician, I observed that it is rare for the filaments in tubes to burn out whereas a screen grid in a pentode output tube that's biased too low can develop hot spots, visible when peering through the holes in the plate, leading to catastrohpic failure especially if the tube is from a certain factory which cranks out otherwise very cost-effective tubes.

I'm not asking anyone to take my word for it because as a company rep I expect that anything I say will be viewed with skepticism, but then I wouldn't be surprised if this stuff was well known since Edison's time.

http://donklipstein.com/bulb1.html#wbt

I'm sure everyone here has looked inside a bulb that just failed and noticed that the filament is severed somewhere between the supports. There is no filament in an AVM/D outside of the front panel display.

Getting back to turn on/off spikes coming through speakers, which is more a tick than a pop as any AVM/D owner knows, consider its loudness relative to the loudest sound your speakers can make when playing music (the speaker can't tell whether the current it's seeing is music or noise), or if so inclined try to find any citation of an AVM/D turn on/off spike leading to equipment failure. I've never heard of such a thing and for over a decade I received all the problem reports.

Is it possible to update the AVM 40 with the latest versions of ARC?

It has had the ARC upgrade.

You're right, of course, Nick. Unlike the olden times, these days it's rare for surges caused by turning off equipment to damage speakers. I still have memorable experience in the 70's with a HK Citation Pre and Amp which did fry my tweeters.

As for tick or pop, it depends on whether there's a biggish woof in your speaker system.