CamT's build thread

Rob - did a little filming today. I couldn't find the microphone for my iPhone so I just taped it to the diffuser (my phone!). Here's a video showing various speeds with Virb (basically a GoPro) as well as the external mic for comparison. The Virb is better at picking up a wider frequency range - so the bass sounds better through that audio channel. The iPhone picks things up a little more clearly, the exhaust would sound better if it had a wider frequency range.


Some clarification -

"Interior mic" is the Virb on its own, untouched.
"External mic, reduced 50%" is just me knocking the volume down 50% to help even the levels across the clips.
"External mic, background reduced 50%" is a feature in iMovie, it can filter and knock out background noise. It ends up quieting the sound quite a bit and highlights changes better but doesn't sound that great to me. Maybe with a better mic it would work better.
 
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Went out for a canyon drive with the local Audi club - it's got an Audi transaxle, that counts right?

I had an issue with the car not wanting to start again, on the surface it seemed just like my fuel issue except this time fuel pressure was all good. The battery seemed fine and the starter motor sounded strong. Just didn't light the engine. I'm leaning toward some type of heat soak/electronics issue for now. I have my ECU and fuse box located in the right pod; it's getting pretty good airflow while I drive but once I shut things down then the air in the engine bay is likely pretty toasty. I also put my hand on the rear clam after shutting down and was pretty surprised by how hot the rear clam/air scoop area was getting. I'm thinking some thermal barrier in this region will be a good future project. I may also install a fan in the engine bay to help circulate air while the car is off.

 

Dan Carter

Supporter
Cam...watched the video, looked like fun. The starter sounded strong enough during the start attempt so heat soak there may be off the table. I’m watching your evaluation with keen interest, so keep us up to speed on what you find. We will let you do the investigating while we wait with a beer......lol.....then we will adjust accordingly.
 
Dan - actually, it was a really good exercise of the potential MAF relocation mod. There were plenty of instances of off-throttle rolling to idle and the idle performance is near oem level now. The idle speed is higher than typical at 950-1050 but I attribute that to the cam. But the ability for the computer to catch itself and get back to a relatively steady idle is noticeably better. I would highly recommend moving the MAF so it’s about 6” in front of the throttle body if you’re running the usual 4” intake tube everyone runs. I’m starting to think my idle quality issues were largely due to the MAF getting turbulent air from the filter.

I have a Dakota digital GPS signal feeding the VSS and my tuner has already made adjustments to idle targets - but neither of those seemed to help much about 6 weeks ago. I will say air temps were colder back then but the early part of this drive started in the low 60s.

As far as vehicle handling and ride quality, I can say at near triple digits the car felt great when those speeds were relatively safe. In Mexico.
 
Cam, I happen to be digging through my tool chest and came across a dB meter I apparently bought or got to review at some point. I pulled it out and tested it on the way to work in the Audi and measured 67-68dB at 80mph. 91.7dB max with stereo at level 22 out of 30. The P-Zero tires are extremely noisy and also just removed my rear mufflers. I wish I had found the meter a few days ago before i removed the mufflers, although it's barely any louder in the car at speed. When the SLC gets here (I go to mexico to test drive it while it's not registered), I'll relay how loud mine is for comparison.
 
Del - sweet! The Audis are on the quiet side for most cars, even with an exhaust mod. But I’ll be really curious to see the difference in our cars. I suspect part of the reason (ok most of the reason) I find the car loud is because it IS - I’m running resonators and not mufflers. They’re basically straight through with some perforated mesh along the walls for a short run, no baffling at all. If I had to do it all over again I don’t think I’d go with a more traditional muffler - the exhaust sounds awesome as is and if I’m going to do a long highway cruise the noise canceling headphones turn it down to Audi levels or better. Plus you can pipe your music and phone calls into the headphones. Just pop them off when you get back into traffic.

On the meter - set it on “slow” if you have the option to knock out any spikes. Do you have an ETA yet?
 
Del - sweet! The Audis are on the quiet side for most cars, even with an exhaust mod. But I’ll be really curious to see the difference in our cars. I suspect part of the reason (ok most of the reason) I find the car loud is because it IS - I’m running resonators and not mufflers. They’re basically straight through with some perforated mesh along the walls for a short run, no baffling at all. If I had to do it all over again I don’t think I’d go with a more traditional muffler - the exhaust sounds awesome as is and if I’m going to do a long highway cruise the noise canceling headphones turn it down to Audi levels or better. Plus you can pipe your music and phone calls into the headphones. Just pop them off when you get back into traffic.

On the meter - set it on “slow” if you have the option to knock out any spikes. Do you have an ETA yet?
I'll be glad when it's time for new, quieter, tires! Even with loud tires, it's so much more quiet than my old vette. You should test dB in your Audi out of curiosity. I'd like to tell you I'm running mufflers, but I actually have no clue. I just asked Allan to use whatever people typically use (Magnaflow maybe?). Mine is exiting through the diffuser so I'm kind of excited to see how it'll sound compared to around the license plate. The meter doesn't have many options, just on/off and min/max. Does have a illuminated LCD, lol.

I finalized transport this morning and put in que. Said it'll be a couple of weeks, but could be sooner. With my luck it'll be a month before it gets picked up, ha. Just patiently waiting on transport so I can get started on registering it....and legally driving it!
 
My wife’s Q5 measured 88-90 dB from 60-80mph. I’ll try in the S5 next time I remember, it’s got the Milltek non-res exhaust.
 
My wife’s Q5 measured 88-90 dB from 60-80mph. I’ll try in the S5 next time I remember, it’s got the Milltek non-res exhaust.
I figured it'd been closer to what mine is, but then again we are using different instruments to measure. I'm curious to hear about the S5 with the Milltek. Little envious actually, although as cheesy as deleting mufflers sound I love how it sounds. Wouldn't mind some more sound, but then again with a 5 month old probably best I don't. :)
 
Cam, I happen to be digging through my tool chest and came across a dB meter I apparently bought or got to review at some point. I pulled it out and tested it on the way to work in the Audi and measured 67-68dB at 80mph. 91.7dB max with stereo at level 22 out of 30. The P-Zero tires are extremely noisy and also just removed my rear mufflers. I wish I had found the meter a few days ago before i removed the mufflers, although it's barely any louder in the car at speed. When the SLC gets here (I go to mexico to test drive it while it's not registered), I'll relay how loud mine is for comparison.
I suspect your meter is using an A-weighted scale; I typically leave my meter in C since that's the mode I normally use when calibrating my theater room. I believe the A weighting gives you a value that's more relatable for the human ear whereas the C takes all sound energy for all frequencies and gives you a value, with very little adjustment.

In the office, with one conversation happening a few cubes over I'm measuring 35-40dB (A) and about 53dB (C). When using the A measurement sound energy is effectively "deleted" for frequencies most human ears can't hear (very low and very high). I just downloaded the "NIOSH sound level meter app" and I'm using my iPhone's internal mic for this A/B test right now. It's probably debatable which scale should be used for the purposes of this conversation but there are aspects of being in a car that can drive comfort that are based on frequency - for instance that very low frequency booming sound you can generate by cracking just one window open. If we were taking this measurement with the A rating selected I suspect it wouldn't show much energy - but throw it on C and you'll find it jacks the value up considerably.

My meter is the old analog Radio Shack unit that's decently calibrated and I've correlated it against the mic I use to calibrate my theater room - it's within 1dB for most practical frequencies (less accurate as you get deeper into sub-audible levels). I'm also holding the meter up, closer to shoulder level and to my right. The following info was measured with my Radio Shack meter, C weighting, slow setting.

My S5 is on relatively new (less than 1000 miles) Pilot 4S tires at about 35-38psi (I forget now) and I have a decent amount of suspension work (Bilstein B16 coilovers on comfort, solid end links, stiffer sway bars) - so possible some differences in our cars due to the suspension work.

On my S5 at high idle I'm getting 76-80dB sitting in the car, windows shut and radio off. At normal idle it comes down to ~74-76dB inside the garage and out in the open street.

During moderate acceleration I'm seeing ~100dB just before shifting. As with the Q5, sound levels seemed to be pretty independent of speed. I was measuring ~86-90 dB under light acceleration/cruising from 60-80mph. With my foot completely off the throttle, drive mode, 7th gear, cruising at 80mph I saw maybe ~2dB drop - so the variation in road and wind noise seems to drive more change than being lightly on the gas to maintain speed. That seems to match subjectively with what I'm hearing.

I'll try and repeat the measurements on my way home using the A scale.
 
That makes sense why the outcome is so different, I have much to learn. :) I'll have to do some WOT runs to see what the dB peaks at for mine as well as some other levels like you did. I was kind of surprised how high mine is considering OSHA requires ear protection at 85dB.

Here's the specific one I have, I've only had it for 2.5yrs it seems, lol. Definitely nothing fancy, but least I can consistently see different levels between Audi and the SLC, would be curious to do wife's little Terrain as well.

https://www.amazon.com/gp/product/B00ECCZWWI/
 
On a side note, do you have pics of your movie room on FB maybe? I'd love to see it, I have a small one and by far my favorite room in the house. The shop my favorite building though, lol.
 
That makes sense why the outcome is so different, I have much to learn. :) I'll have to do some WOT runs to see what the dB peaks at for mine as well as some other levels like you did. I was kind of surprised how high mine is considering OSHA requires ear protection at 85dB.

Here's the specific one I have, I've only had it for 2.5yrs it seems, lol. Definitely nothing fancy, but least I can consistently see different levels between Audi and the SLC, would be curious to do wife's little Terrain as well.

https://www.amazon.com/gp/product/B00ECCZWWI/
With my meter on A weighting here's what I get:

Cold/high idle - ~60dBA
Hot idle - ~65dBA
Highway drive, 60-80mph, maintenance throttle in "drive mode" - 68-70dBA
Moderate acceleration, Sport mode, peak just before shift - ~80dBA

I think what these readings is telling me is there's a lot of content in the lower frequencies, where the A vs C weighting makes a big difference!
 
On a side note, do you have pics of your movie room on FB maybe? I'd love to see it, I have a small one and by far my favorite room in the house. The shop my favorite building though, lol.
No pics of the finished room posted but it's not much to look at; small and square basically. It's turned more into my daughter's play room now than as a serious movie room anyway. I've got a 60" Panasonic Z series plasma and I'm running a 7.2.4 Atmos system mostly comprised of Energy RC series speakers. Currently have a Denon from about 2 years ago for processing.

There are some pictures of the room being built in my home reno post here (about halfway down): https://socalslc.com/2017/02/06/10-this-is-not-the-post-you-are-looking-for-or-maybe-it-is/

The loveseat has since been replaced with 3 leather theater recliners, that was a nice addition. I plan to make some DIY acoustic panels but that's pretty far down on the to-do list for now.
 
No pics of the finished room posted but it's not much to look at; small and square basically. It's turned more into my daughter's play room now than as a serious movie room anyway. I've got a 60" Panasonic Z series plasma and I'm running a 7.2.4 Atmos system mostly comprised of Energy RC series speakers. Currently have a Denon from about 2 years ago for processing.

There are some pictures of the room being built in my home reno post here (about halfway down): https://socalslc.com/2017/02/06/10-this-is-not-the-post-you-are-looking-for-or-maybe-it-is/

The loveseat has since been replaced with 3 leather theater recliners, that was a nice addition. I plan to make some DIY acoustic panels but that's pretty far down on the to-do list for now.
I remember seeing that blog, but apparently I never read it all. I see green glue! When you start digging into theater rooms, it's quite unreal how much information is there about isolating walls, double entrance doors, double/triple sheet rock.

Sounds like mine, rectangle. Wide enough to fit 3 leather movie chairs and a 110" screen. Nothing crazy, but I couldn't live without it. As of last week the projector bulb life was 7201hrs in 4.5yrs of use, lol. I can't believe that bulb has more than 2x exceed it's lifespan, knock on wood.
 
I remember seeing that blog, but apparently I never read it all. I see green glue! When you start digging into theater rooms, it's quite unreal how much information is there about isolating walls, double entrance doors, double/triple sheet rock.

Sounds like mine, rectangle. Wide enough to fit 3 leather movie chairs and a 110" screen. Nothing crazy, but I couldn't live without it. As of last week the projector bulb life was 7201hrs in 4.5yrs of use, lol. I can't believe that bulb has more than 2x exceed it's lifespan, knock on wood.
I lucked out on the green glue - I bought an overstock case from a construction project, got more than 2x than I needed but was able to turn around and sell off what I didn't use. Overall cost for my green glue came out to about $100! That stuff ain't cheap ... like most things audio, I'm not sure just how much of a difference it makes but between that and all the sealing, the rest of the house isn't rocking when the movies are turned up.

That's an impressive bulb time! I'm holding onto my plasmas as long as I can until the large OLEDs get down to a more reasonable price.
 
I lucked out on the green glue - I bought an overstock case from a construction project, got more than 2x than I needed but was able to turn around and sell off what I didn't use. Overall cost for my green glue came out to about $100! That stuff ain't cheap ... like most things audio, I'm not sure just how much of a difference it makes but between that and all the sealing, the rest of the house isn't rocking when the movies are turned up.

That's an impressive bulb time! I'm holding onto my plasmas as long as I can until the large OLEDs get down to a more reasonable price.
I regret not using green glue and price was the factor. I did double sheetrock though, but I wished I'd done more sound proofing, but at the time with building the house I was attempting to not go overboard. Hindsight is I should have, my wife didn't mind going overboard, lol. I do have a SLC, so I shouldn't whine, lol. I didn't do any high end equipment in mine, I think I've watched 1 Blu-Ray movie. I watch stuff on my HTPC 90% of the time.

I keep hoping this bulb will last until LED movie projector prices come down. I won't miss the warm-up time or the heat!
 
Aaaah, it seems like an uphill battle these days. I was able to get a little more clarity regarding the issue I had last week during my canyon run with the local Audi group. It's highly likely I've got some kind of voltage draw issue during startup that's causing my system voltage to drop too low for the ECU or ignition system to be happy. I'll have to run a voltage drop test; I literally just installed a new battery with a recent manufactured date (Optima yellow top). So I'm leaning toward battery or starter at this point. A quick visual inspection showed all my cables to be well secured and no visible corrosion.

Anyway, the reason I know this is because I took the car out for a spin this past Sunday and it wouldn't start up after refueling. My very wonderful wife was kind enough to load the kid up and come rescue me with a jump - started right up. I'd let the car cool down for about an hour and that didn't do squat. IIRC voltage on my dash was ~12.6V which means about 12.7V at the battery terminals.

Pic for proof:



Prior to that I had a fun time driving around town shooting a few last bits for my latest YouTube video - of course my in-cabin camera died so I really had to work to put something usable together. I think this is likely to be one of my last videos, it's actually the video I'd wanted to put together all along but just didn't have enough footage to stitch the thing together. Finally got enough to throw it together and call it GE, good enough.

At one point in my life I had to stop riding sportbikes on the street - I just couldn't keep my speeds down. You're taught to ride offensively rather than defensively, keeping traffic behind you means you only have to worry about the dangers in front of you. I seem to have adopted a similar approach for the SLC. Not the best thing to do if you're trying to stay under the radar, the car already sticks out like a sore thumb and moving faster than traffic is a sure way to get you noticed by Johnny Law. For some reason my car really likes 90mph. :oops:

OK, here's the video, hope you guys enjoy!

 
A Quirky Cam Video with High Carbon Content ! I like it.

The audio track is critical for relaying the sound 'feel' of these things. Following your lead, a cell phone was taped under the rear clam, this was the only way to get close to capturing the high pitch of the supercharger. To conceptualize in your head is easy, the execution (like when building the thing) is much more difficult. I'll get there with a vid, someday.






PS "You're taught to ride offensively rather than defensively, keeping traffic behind you means you only have to worry about the dangers in front of you."

Amen.
 
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