Marantz AV8801 Preamp/Processor Official Owner's thread - Page 114

LOL...I doubt she'll read it. She doesn't understand all the techno mumo jumbo.

Wow eight 18" speakers, you must have a big room, that is a lot of air to move. How many cabinets are they in? Do you use 1" ply? I built two Altec voice of the theater cabinets back when I was in a band to use for our PA, one 12" in a huge cabinet with a horn on top. Not for hifi mind you but we could not afford to buy the originals and the plans were available. I understand the savings.

The article was clear that if you add a sub or subs to a 2-channel or Multi- channel system that you must XO all speakers at 80hz and plug the bass ports to eliminate bass FR cancelation, phasing and polarity issues.

Quote from SoundDoctor All About Subs:

"Home / HI-FI / 2-channel / Audiophile / Surround Sound systems: There is ONLY ONE truly correct way to "add a sub" to a system in an controlled listening room situation: you must correctly cross over the 2 sealed cabinets; and their timing must be correct. ANY other method will lessen the focus and clarity you have tried so hard to preserve.

with home theater setups where the customer THINKS that the front speakers are "full range". Even so, the BEST approach is to seal the ports, operate the 5 channels as "small", crossover at 80 (or even a bit higher, but NEVER lower)

Actually adding a crossover is really a WIN-WIN situation:

WIN # 1) Since you are now NOT putting in 20 Hz - 80 Hz into the mains you are not using up the available LF cone movement with bass, so the LF cone in your mains is able to play its higher freqs (up to IT'S crossover point) much more cleanly. You get an apparent 6dB or more dynamic range. You can play your system LOUDER, and also with less compression distortion in the LF driver when you're having that Saturday night dance party and you're playing urban bass technopop at 110 dB. Really.

WIN # 2) Since you are not putting bass into that same driver you are not Doppler modulating everything between 80 and 600, or whatever the next crossover point is. This means cleaner mids. By far.

WIN #3) You are not sucking current out of your main power amp at low frequencies, so there is more current reserve to play those highs louder...

WIN # 4) Since the cones aren't moving as far at the low freqs the driver itself is not generating as much back EMF therefore the damping factor and all of its issues are greatly negated. And you don't need to run silver plated cold water pipes to your mains as speaker wires because there is less current draw by the speakers.

WIN # 5) Freqs below 80 are now NOT causing transient intermodulation distortion with the higher freqs (and vice versa) in your power amp. Cleaner still."

Interesting

Thanks for confirming. So I think then we can safely allow you to determine the best setting for the LFE LPF based on your own sense of aural delight.

Don't you have fourway speakers.
Don't you trust your crossovers in the speakers to work properly?

- Rich

Where can we find a list of serial commands the 8801 supports?

Thanks,
Dave.

Dahl,

Some good points were made in that article but to say you HAVE to plug all ports, with today's processors and Eq equipment is a little absurd. The whole sending your low freq content away from your main and to your subs and the decrease in intermodal distortion is great and true. The added efficiency your mains will now play at should ring clearly through the tested temperatures of your front stage amp at the least. The added dynamic range that it frees up should be pretty obvious.

Now back to the plugging ports thing. I have to agree that plugging ports will make the system easier to integrate, but it is NOT the only way to do it properly. I so wish modern pre's and Avr's had the ability to adjust crossover slopes, but simple crossover adjustment can still suffice. The distance settings for the speakers can also help over come phasing issues. Bottom line there are plenty of ways to make ported and sealed work together.

If you want a standalone unit, the dcx2496 does a killer job, and really, you can just have it on your sub channel to help with the blending of the system. I think his whole point of plugging the ports on your mains is that you don't need that additional bandwidth since you are only cutting the mains off at 80hz as opposed to needing the port for them to extend full range.

Those xo's are between speakers, not on the ends of the chain. You still need proper integration on the low end. Trusting the xo's in the speaker is fine, but the bottom just has the port tuning frequency corner where the speaker begins to rolloff, it has nothing to do with the XO.

Dave,

have you had any luck with getting URC's CCP updates to pull in this unit in their database? still nothing on my end...

The problem is not in the mains or the other speakers in the room and their quality, it's how the bass frequencies play well with the sub (s). If no sub no issue just XO all speakers at 80hz except the mains. If you add a sub to the mix then it needs to be dealt with properly. At least that's how I understand the physics that is unchanging.

Nope. I used the HEX codes to program rudimentary commands (input, power on/off, volume, mute), but haven't done anything else. I'm waiting until URC has them in the database and I'm going to do a full reprogram (dreading that!).

I have the complete list of serial codes for the 8801: PM me with your email

several new codes in this document

Mark

As I understand the ports have to be dealt with as if adding another sub into the mix, each port as a separate entity.

Ok I am going to quote SoundDoctor again:

"The ONLY correct way to add a sub to system is to define everything ABOVE the sub's range as an entity; clearly define the impulse, phase, and lastly frequency response of this entity; and then make a new "2-way" system where the sub is one way and everything above it is the 'other' way. The parts must be combined correctly so that there are no cancellations and no smearing of time-related musical events."

This is for instant access, all should read all of the SoundDoctor multiple docs.

On ports, phase and coupling:

"Therefore the MOST desirable scenario in a HT situation is to best couple the sub(s) to the room FIRST, and THEN timing and phase match the sub(s) to the rest of the system."

"As you go lower and lower in frequency, at some low frequency the air pressure from the LF driver and the air pressure from the port are exactly opposite each other, so they cancel, and there is no more audio at that frequency: it disappears. This defines the -3dB "cutoff" point of the cabinet in question. When the manufacturer of a speaker cabinet defines the frequency response (i.e., 37 Hz - 20kHz +/- 4dB) this is what is defined by the entire arrangement of the port and the air in the cabinet and the driver."

"That means IF you were to simply put those same frequencies through the mains and the sub (that means with no crossover, and this is the mistake that nearly everyone makes) you would now have 3 sources of LF energy and differing phase: the 'main' LF driver, the port, and the sub, all fighting with each other. A further corollary is that since the air inside the [mains] cabinet is elastic, the phase relationship of the port air to the driver air is also a sliding one; that means it's "out of phase" — and smearing — over a wider range of frequencies than you might think."

"If the port is on the back, again a cheap attempt to use the back wave bouncing off a wall to give 'additional' bass, you have the ADDITIONAL issue of the transit time it takes for the back port pressure (already delayed because of the elasticity) to leave the cabinet, travel back, hit a wall, and bounce back around the front of the cabinet again; therefore this LF wave MIGHT be "in phase" with the front driver BUT BE 360 OR EVEN 720 DEGREES LATE; therefore it sounds like the bass frequencies are ok in the frequency domain but the IMPULSE RESPONSE is now muddied.

Also, in the case of back ported or (type 5) dipole speakers, since the path length from the back of the speaker to the wall and bouncing back around to the front of the speaker is a fixed physical entity, at some frequencies you are adding and at some frequencies you are canceling: you have simply made a physical/mechanical frequency comb filter that you can't do anything about. Sound Lab's answer to this (for use with their flat panel electrostatic speakers, which are dipoles) is they sell you a "Sallie", which is an absorber to absorb the entire back wave output of the electrostatic panel. Since now there is no comb filtering; all you are therefore hearing is the front signal."

PORTED SUBS

"A ported sub for home use is even more wrong than ported mains. Now you would be attempting to acoustically add together in the room at least SIX low frequency sources with differing phase and frequency slope conditions: the LF drivers in your two mains, their ports, the sub driver, and its port. In addition, since it's a bandpass it cannot go down low enough for serious Home Theater effects."

"Some better speaker companies that make "large" speakers (such as B&W) are aware of this port issue and supply port plugs just for this purpose. Kudos to them."

"In addition to all the above, there is the complex issue of the "main" speaker you are coupling to. There are essentially 6 types of speakers that exist:

1) sealed
2) port in the front
3) port in the bottom
4) port in the back
5) a dipole, which is a flat panel such as an electrostatic (Sound Lab, Magnepan, Quad, Beveridge, Martin Logan, etc.)
6) an true omnidirectional system such as the MBL or the BEOLAB 5."
Edited by dahlgren - 2/28/13 at 8:37am

Hi bill,

same problem here and Kal Robinson gave me that answer :

So i did bumped the speaker's level by 12dB as i dont use the dynamic volume.

Give it a try.

Hi,

i use the oppo-95 in HDMI->pure direct path.

Do you find a big SQ difference between oppo-105-analogout-pure direct and oppo-105 ->HDMI->pure direct ?

thx.

The problem is not that the speakers are incorrectly designed, but that their placement in the room makes it very difficult to obtain uniform bass. The room dominates the output, irrespective of speaker design. The best place for main speakers is almost never the best place for good bass. A very few speaker manufacturers have attempted to ameliorate the problem through unusual placement of woofers, but use of multiple subwoofers correctly distributed in a room and judicious EQ make for better bass than even the best full-range speakers.

Yes, I do.
But the BDP-95 has similar analog output performance (although the RCA's dedicated might be a bit better on the 105).
Why not correct just the two dedicated RCA outs to the 7.1 in and try it?

If you can program a remote, you can switch between inputs on-the-fly. Otherwise you can use the menu.
There change in the sound quality on the analog inputs switching between Pure Direct and Direct.
If I listen to a live recording with ambiance, there is a collapsing of the sound-stage and a loss of instrument decay.,

Before folks, poo poo this, ask yourself, why did Marantz include Pure Direct.
It does not seem to occur to folks that there may be an equally valid reason for its existence as their is for Audyssey

- Rich

And there are good many that are well designed.
And perhaps, they are a bit better at it than Audyssey is at correcting the resulting deficiencies.

Every time, I add processing I find a change in the sound quality and a reduction in detail.
I operate under the theory, that if that detail and precise timing is somehow lost in processing, further processing will not restore it.
This is what I hear. I understand that others make different choices.

Here is a quote from Kris Deerings review of the Parasound Halo analog Pream and Amps:



- Rich

from the 8801 owner's manual (pure direct playback, P.86):

From which modes?

My initial question was : in pure direct mode, do you hear an SQ difference between HDMi and analog? i did try the dedicated balanced stereo out (same dacs for both 95/105) and results differs
depending on the recording. I will have to try all 7.1 analog out for MCH sacd.

I can hear a different in Pure Direct mode with the Blu-Ray input selected ranked:

1. 7.1 Analog input - Provides the fullest sound, greatest decay and imaging.
2. XLR - Similar the the 7.1 a bit more aggressive and bright. A hair less imaging.
3. COAX - Similarly still but with a bit less low end an imaging.
4. HDMI - Sounds good but with noticeably less ambiance and imaging

These are diffenences that can be heard in a A/B comparission.
However, if I just started playing a disk, it would be difficult to notice.
With me, I am usually sitting at my computer and after a while, I think: This used to sound better

- Rich

hi guys,

it seems i am getting ready to get one.


i don't wanna break the forum's rules. but if someone suggest me a dealer for the price cheaper than 3k, it would be appreciated.


just send me a pm.


thnks

How did you compare did someone else made the switch?

I made the switch.
But I have have others over and made the switch and asked them to tell me if and when they hear a difference.
It is hard to find anyone with the level of interest that I have

Ambiance is not something everyone is tuned into. I also think your room, speakers and seating position come into play.
I often listen to the other sounds in a song: drums sticks decay, symbols, and backroung violins for pitch.
There are times that I hear a sound and think I know what it is, but by switching sources that actual instrument becomes apparent.

- Rich

Not the best option as your speakers are still not getting eq'd properly by audyssey at a -12 end result, and bumping everything up 12 dB will inherently add all kinds of other issues. I would never suggest this as a good alternative to just getting some line level attenuators. It has even been tested that distortion/clipping on the pre's outputs could start to creep in a +2 on the trim levels in some pre's and Avr's. Having someone your trims well above that is not something I would want in my setup.

Dahl,

Read it all, and it all is spot on, but only in the last 2 pages does he really address issues that truly affect anyone using a modern receiver. The other 16 pages deals basically with splitting the left and right signal of a stereo preamp to be able to add a sub in. I have manual and automatic methods to do the things he Suggests but in accordance to his diagrams he is showing the added delay caused by an amp for the main speakers and that the sub is then off in the time freq. well, so the sub doesn't have an amp? Wrong, it is just in with the sub box in his case, so you are back to same wavelength, or so you hope.

The point he makes about the porting is alright. Like I've said, I don't like ported subs, but I see the point of them in some cases, and as the good dr. stated as well most people prefer a little smearing of the time domain down in the frequencies. I'll expound more on all this later. Typing in my phone is no fun.

You are correct: line level attenuation is necessary and I have pointed this out in the past.  Somehow, I often forget about hitting the attenuation limits, perhaps because I have never come up against this problem myself.  

 

I will delete/correct my earlier post.

My points are all posted through the article areas that you posted in Blue, but to add, I agree with a lot of what the "Doc" says, but he is once again essentially outlining a situation that most of us are not doing. I don't bet anyone on this thread is "Y-splitting" their left and right channels to add a sub, and this is the basic premise of 90% of the paper. Thank goodness the marantz has a separate sub out which takes care of a lot of the problems that he is talking about, but certainly not all of them. My contentions don't outweigh my agreements, and especially when it comes to the whole "ported sub" part as I have always preferred sealed alignments, and for a good reason, they just play better with the rest of the system. Try making a horn sub work right haha, it can also be done, but in ported and horned sub alignments, I don't suggest hoping that the AVR or Pre is going to be able to do it all by itself, it may take another piece of to assist

Beast audio, from my iPhone
Quote:
"This is where the paper takes off assuming you are taking left and rights out of a 2 channel Pre and trying to split the overall signal to a sub, which is completely different from what 90% of those on this thread are doing."

My take on this was the sub to be considered the bass speaker for your system, HT or 2-ch. thinking of the sub as just another speaker in the cabinet as a designer would designing a speaker. So getting the frequencies out of the boxs that can't fully reproduce them is the idea. Getting the port out of the way to smooth the transition.

So we are in agreement on all of this. I guess after crossing over at 80hz the ports become low-mids and almost irrelevant.

Do you think it a good idea to plug the ports on my two subs? One is dual 12" down facing and the other is front facing 12".

Fact is my system as it is sounds excellent. I have noticed some muddy bass but not on all discs. I have some discs tha blow me away, some muddy, some shrill high end. I take that as bad engineering in the recordings.

Still need wall treatment and Audyssey Pro. After that I'm good.

The key point here is the best main speakers in the world cannot overcome placement compromises dictated by positioning requirements of the mid and high frequencies. The single best method for even bass is room positioning. Traps can help but are problematic below 40-50hz. Audessey, EQ and PEQ can help in some cases and in others (ie. primary listening position nulls) are useless.

Are you using a URC MSC-400?? I know some posters are....I didn't use hex codes but rather the mnemonics (SDHMDI, SD7.1 for HDMI audio and 7.1 respectively). Compared to the rest of the MSC-400/MX-980 build, adding the 50 or so serial commands for the things I needed didn't seem to bad...