Bit Ten Install and Tuning

pentoncm

I'm finally learning how to get the midbass area in order. I feel that the hardest part is the 125Hz and 160Hz bands because those frequencies tend to get really boomy as you turn the volume up. As I've brought down these frequencies I've brought up 80Hz on the front by a little making it fuller sounding but not overwhelming.

arun1963

Would just add a couple of things to that. 100hz will also add a lot of boom the MB, so you need to watch that. Typically, 80hz should be a touch hotter than 100hz. 60hz is good for that 'rumble' in your mb, without adding boom.

The other thing is 'balance'. Lets say you breakup the sound into say five ranges, sub, MB, mids, upper mids and highs. For things to sound good there has to be a good balance across these ranges, including the transition between them. Now, if you cut or boost in one range you may need to cut/boost else where as well in order to maintain that balance. Unless you're cutting a range that was too hot to begin with. Even then, once you cat a range you may discover a problem elsewhere that was being masked earlier.

MacLeod

160-200 Hz is always a pain to get right. 1 db too little and it gets as thin as paper. 1 db too much and it sounds way too over-exaggerated.

I generally keep 160 cut pretty good cause its the most boomy but keep 200 Hz up a little more.

I really like a little over use of 100-125 Hz cause it really adds a lot of balls to the midbass and really the only place it sounds too hot is in the male voice but even then its worth the trade off.

80 Hz is the one I usually keep cut pretty good. I've got them at -5 (L) and -3 (R) right now but 100 is flat and 125 is only down 1 db or so.

63 you need a lot if cause that where the punch starts. 40-63 is where you want plenty of energy for. nice, robust kick drums and such.

arun1963

Mac, can you please do me a favour? Can you use your spl meter to measure 60-200 and then 1-1.6khz, with all drivers playing? I'm really interested in how these ranges are balanced in your sound. I know it's relative to how everything else is set but, I'm curious about the relation between these frequencies.

arun1963

Haven't really done any tuning for a while. Wasn't really listening for about the last three weeks. Things have settled down a bit, for now. Spent some time listening on the way back from work and the sound needs some work and I've finally got some time:biggrin:.

pentoncm

I've been making great progress now. I've been tuning to the same 3 cd's for the past two weeks, probably put in 8 hours of tuning total in that period. The Cd's are

(1) Collective Soul - Dosage ; this is used because there are some really nice bass lines combined with slightly overdriven guitar/acoustic guitar and the occasional string arrangement.

(2) Tool - Lateralus ; Use this because its a great album with great dynamic range and there are 2 or 3 tracks that are instrumental with great drum and bass tracks. Nice to hear what the whole drum set sounds like here.

(3) A Perfect Circle - Mer De Noms ; I recommend this CD highly because it will tell you immediately if your MB is in order. Mine was too bloated so Judith sounded horrible and muddy. It has helped me tell that it wasn't the 80Hz to 125Hz that was too high, it was my 160Hz to 250Hz area that needed fine tuning.

I listen to mainly rock music so that presents both benefits and challenges.

Pros: I play guitar so I know what it should sound like. I've been listening to rock albums for years through my tower speakers.

Cons: Guitar is a pain in the **** to tune because you have the fundamental but then you have about 4 or 5 sets of harmonics on top of it. So if you detect a problem you have to check multiple points on the EQ.

My right side was a little thin in the midrange area. I had identified that notes for the specific chords being used were on the 400 (fundamental), 800 (1st harmonic), 1.6 (2nd Harmonic)kHz etc. bands. My question was did I need more 800? Yes I did but it sounded bad if I boosted 800. The problem was that 1.6kHz was too hot. So basically I needed to boost 800 while cutting 1.6kHz leaving the sound more natural and full without the harshness I was previously hearing. I went up an octave and checked 3.15kHz to check if that needed changed, I ended up bringing it down .5db.

My 80Hz values are in line with what Mac is using. I have my crossover at 60Hz with the L/R filter. That means that 80Hz is reduced by -2.5db just by using the crossover. My left side I have cut it an additional 1.5db which would be equivalent to -4db on the left. My right side I have left flat so that would be equivalent to -2.5db. A Butterworth filter at 60Hz barely cuts 80Hz leaving you with more necessary EQ cutting to get to a similar level. I've been running 100Hz and 125Hz around -1.5db on each side but I'm continuously tweaking.

pentoncm

By the way.

Thank you guys for all of the help in tuning. I've only been seriously tuning since September with my bit Ten; it was about a year before that that I started messing around with my 7band eq on my previous pio deck. I feel as though you guys have been really helpful and there is really good advice here without all of the garbage like on most of the other forums.

I feel good about my settings because although I keep tweaking them, they are similar to what you guys are getting. I am now getting much better at tuning by ear and my EQ curves look like a hybrid of both what both Mac and Arun are using. My 80Hz to 1.6kHz area is similar to Mac, my 2kHz and up area is similar to Arun.

arun1963

I'm in the car, connected both online and to the bit10. Going to try to make this post an on the job blog kinda thing. Not sure how this is going to turn out.

Album playing - Peter Gabriel New Blood. Good recording, done with a live orchestra. A fat and dynamic MB. It sounds great on the 2ch. Fleetwood Mac their 1975 eponymous album. This is one of the best cd's I have for recording quality and another cd with great MB and dynamics. I also think this is FM's best album. I agree with Penton when in tuning mode one focuses in on a few albums. Tool I know but the other two I had to google :cheesygrin:.

Listening volume - 46/64, which translates to a dynamic range of 55-90db and a mean of ~78-80db. On the FM the mean is slightly lower at ~76-78db, but the dynamics are 50-95db.

Ambient noise - ~27-30db's. I look at that as the noise floor. Whatever measures 30-35db is probably getting lost in the big picture.

Measuring Tools- The spl meter and the true rta app on my wifes droid. The spl meter is out in circulation. But the phone and apps are fairly close to the spl meter. At least in the 300-3khz range. More power to $0.99 apps and the mic on the S2.

This is the impression after listening to tracks 3 and 7 on the Gabriel album. San Jacinto and Mercy Street. The great thing about using this and the FM album is the vocal quality of PG and Lindsey Buckingham. One is a male singer with a gravelly / grainy voice and the other is a female singer with the same. You want both voices to hit the dynamic peak without breaking up. Thats how it is on the 2ch.

The mb is good for mass and quantity, but lacking the dynamics compared to where I've had it at some point. The vocals have a telephony, hollow sound. There is clarity on the highs, but the right side highs are missing a huge bit. Big hole there. I'm sure 2-4khz is almost killed on the near side tweet. Comes from the paranoia of having the near side tweet phsically close and succeptible to comb filtering due to near reflections.

Good news is that the highs on the left aren't smearing, so I'll largely have to reset one side. The lower end needs the instruments to sound more cohesive and smaller. I'm not sure what I was doing three weeks back. Must have been really deep, down a dead end hole:eek:. You're really swimming in a tight space and bandwidth. It's very easy to be flailing against the side of the pool and think you're getting somewhere .

There are different approaches that one can take. The lengthy and correct way and the one I'm going to do, is to first balance for L/R mids only, tweets only and then together to check for the xover range. Check for phase coherence. I would check phase first if I felt an overlap between L/R or if the stage pulled to extreme L/R corners. Then one gets down to level matching and corrections.

arun1963

.............The L/R balance is now taken care of. 40-60 was much weaker from the near side on the MB. As was 2-4khz on the tweeters. That whole 400-800hz zone was way too hot. 160hz is a killer. One side is so much hotter than the other thats its easy to overdo the cutting on the near side (right). It doesn't help that this frequency is CRITICAL to your mb. Exactly like Mac said +1 db is too much and -1db is too little. You are going to use 160 and 400-4khz together, at least for the fundamentals on vocals.

On my eq 80hz is set higher than 100-125hz. This is something I've always done by ear. But some interesting results follow. I like a slightly fat 100-200hz and then play with the balance between 315 and 400hz. The other struggle is between 1 and 1.25khz, whcih frequency sould dominate or should they both be at par. Beaming is at 2.1khz so balancing that frequency with 2.5-3.25khz is another vital point.

With dash mounted tweets I'm giving 2.5-3khz to the mids, with the tweets just adding a touch at the top. The tweets really kick in about 4khz on. 6hz and 10-12khz is key to getting the dynamics right. By now I've moved on to the FM album and the sixth track - 'Crystal' is on its 9th replay. I think I'm going to walk away from this session. I'm giving below the FR for 1/3 octave pink noise at these settings. It sounds great, but it can only be validated tmrw. Sub to Mid Xover 50hz, 36db on the sub and 24 db on the mids. Mid to tweet xover 3.250khz both mids and tweets on 24db/oct.

20hz - 87db
25hz - 88db
31.5hz - 88db
40hz - 89db
50hz - 84db
63hz - 84db
80hz - 78db
100hz - 83db
125hz - 84db
160hz - 88db
200hz - 86db
250hz-88db
315hz - 86db
400hz - 87db
500hz - 89db
630hz - 87db
800hz - 88db
1khz - 86db
1.25khz - 84db
2khz - 85db
2.5khz 80db
3.25khz - 74db
4khz - 68db
5khz - 66db
6.3khz - 62db
8khz - 59db
10khz - 54db
12.5khz - 51db
16khz - 48 db

I'm not sure if the spl meter would measure differently. The spl app on the phone mentions that its accurate for the 300-3khz range. But I'm sure the curve will be the same.

pentoncm

One thing that i've found is that it sounds better me to have moderate cutting at 80Hz but a minimal amount at 100Hz and 125Hz. I highly suggest checking every octave for fundamental-harmonic balance. If this area seems a little too thick check out the two octaves above, commonly 160Hz and 200Hz will make the MB too muddy if they are too high in relation to the octave below.

If 630 and 800 are not in the right balance, your MB is going to be off. Not enough will give you a boomier sound that is a little thin and the bass guitar notes will lose resolution and won't be tight. If there is too much, the MB sounds weird, it loses its depth. When you get it just right the MB is still nice and thick but it gives a nice punch (this range is critical for getting kick drum to sound right!)

2kHz to 4kHz will affect bass guitar notes as well, listen to some tracks where there is slap bass, the slap comes in this range. If the slap seems to jump out at you, something in this range is too hot.

pentoncm

I've noticed the same thing on my droid RTA, it is not very accurate past about 3kHz, it starts falling off too rapidly (much more than the spl meter). Also my droid always showed a big peak at 500Hz on the near woofer and a big dip at 400Hz. When checked by SPL meter this is incorrect, there is a big peak at 400 and a null at 500.

If your 500Hz level is correct, it may be a little hot. I've found that 500Hz is critical for vocals to sound right but too much makes them muddy. In the 315 to 800Hz region, our ears are most sensitive between 400 and 500Hz so you wouldn't want that area to stand out above the rest.

arun1963

The final readings threw me a bit cause there are some differences from what the spl meter measures for the same sound quality. My biggest fear on reading your post was that I had tuned something that would sound like dog this morning. Luckily it sounds good. So either me or the droid messed up the readings. Two hours of alternately tuning and typing is perhaps a bit beyond what my brain can handle .

Typically my 500-800 range will be slightly lower than both, 250-400 and 1-1.5 khz. The highs are also messed up. For some reason the driod is measuring it louder than the spl meter. There's a bigger roll off in the 10+ zone, than what the droid reads.

pentoncm

It should help to use spatial averaging to measure your levels. I'm going to start doing this. You just move the meter around a little bit both vertically and horizontally and take like 4 -5 measurements for the same frequency and average. It is supposed to give more reliable results (I know i get slightly different readings every time when i only take one measurement/frequency). It just makes sense statistically, why go with a n=1 when you can have n=5, in the end it should make things much more consistent.

The new Audison Bit Tune, auto tune package is going to be the first system to do this because it has 5 mic's built in. Maybe because of that it will be able to auto tune a little better than the others.

arun1963

Spatial averaging is used primarily, to over come the so called 'head in a vice' syndrome. You're trying to maintain stability of image while allowing for a bit of lateral movement of the head, which is normal while driving. For me, spatial averaging is something I'd never be able to execute accurately. There's no way I could ensure that the mic's absolute position would stay constant for a given measurement set, much less accuracy at different spots.

The frequencies that cause smearing with head movement, are typically in the 1.5-4khz range. An octave and a bit above the point where the wavelength is about the distance between your ears. ~8-9". When you're balancing L/R, you're typically looking at a fixed spot, let's say the rear view mirror. With your head in this position your ears are in a given phase with the drivers and you're setting things around this phase. Now, when you shift your head, your ears are out of phase from where you set things.

But out of phase for which frequencies? The lower frequencies are more phase sensitive. However, once you have them in phase, the wavelengths are so long, that a 2-4" shift in the heads position is not going to throw them out of phase. But with frequencies of shorter wavelengths, are going to be thrown more out of whack with the shift. Even though they're less sensitive to phase.

A good way to catch these frequencies is to balance for L/R looking at the rear view mirror. Get the frequency centered and then listen while looking directly in front. Does the image shift? Identify the range where this happens. When I set this range, I will centre the frequency and then play it while looking forward and cut the near side a bit. In my case, its normally 80% on the near tweet and 20% on the near mid. That's how I spread the cut. The cut ranges from ~0.2-0.8db, depending on how badly the frequency smears. This gives me stability in imaging, while allowing for a bit of head movement and not affecting tonality much.

I have a 4 hour daily drive to work and back. When I'm got my attention on the road, the perception of imaging seems slightly more important than tonality in the overall experience. Cause even if the sound is focused on tonality, you're going to lose a lot of it to the noise floor. Listening while parked is a different ball game

pentoncm

I have a few comments from my continuing tuning adventure:

(1) I have tried so long to avoid boosting, but it sounds better to me to boost a tiny bit on my 500Hz band. Boost of about .8db on both the left and right side sounds a lot and adds to midbass clarity and punch.

(2) I have been continually plagued by my right side sounding a little thin and pulling the image to the right on certain tracks. I have measured the 630Hz to 2kHz so many times on each side. I had matched it perfectly according to my readings but it still didn't sound right. Basically I had to drop the far side 1kHz to 1.6kHz by an additional .5db. Additionally I had to add an extra 1 db onto the far side 630Hz and 800hz bands.

The meter got me really close but it took some fine tuning by ear to get the left and right properly matched.
You know this could be because 1/3octave measurements simply don't give you a high enough resolution look at the response.

arun1963

Listen to mids only and then the tweets only. The centre image from both should be more or less in the same spot. If one is centred and the other skews L or R you'll know what needs to be corrected.

Mics don't hear reflections. So frequencies that are prone to reflections 400~3.5khz (the lower end is defined by how close your mids are to your dash and the upper limit by how close the tweets are to the reflective surfaces) will sound louder to the ear than on the meter. Same for L/R balance. Use the meter to get close and then use the ears. The toughest to set for L/R balance, is the 1-1.6khz range.

arun1963

Two correction to the above. Firstly, reflections can cause summations and cancellations. Summations are generally easier to catch. Cancellations can be a bit more subtle. This is important when you're level matching in this range. Chances are you will have both issues in this range.

The second correction is that the upper range of reflections is dictated by both how close the drivers are to hard surfaces and your mid to tweet xover points.

arun1963

If you're a floyd fan, try this album in the car and hear how it sounds. Not strictly Floyd but its Roger and thats close enough. Even if you're not a Floyd fan try this album. Roger Waters + Eric Clapton on guitar + David Sanborn on the sax. You cant ask for more.

arun1963

Ofcourse the moot question is if the album cover makes the music sound better. For the inquisitive, the derriere belongs to Ms. Linzi Drew, a softcore actress.

pentoncm

Here you go, Soundman shop with a FLAT RTA for the most part. My biggest problem? He's doing everything outside of the car! You have to check by ear to make sure things sound right. Who pays for this crap are you serious.

arun1963

He's just tuning for a flat response. Ask him to enter one of the vehicles he's tuned in MECA competitions. You don't want a flat response and you have to tune sitting in the car.

jedi-knight83

Hi, I cant PM at the moment but I was going to ask arun1963 if he wouldnt mind having a look on my thread. Im pretty new to the bit ten and to tuning in general and wondered if you could give a bit of advice

thanks in advance

http://www.polkaudio.com/forums/showthread.php?138790-Bit-Ten-tuning-for-a-newbie-)&p=1839573#post1839573