Stereo Upgrade in 991 - SPP
01-13-2021, 10:02 PM
#16
Intermediate
Wow! Not sure how I missed this thread back in March! Very nicely done and super clean.
Nice catch on the balanced outputs from the PCR to the amp. I guess I'm lucky that the JL Audio VX800/8i has differential balanced inputs, otherwise I'd have been battling an issue I wouldn't have easily identified.
Like flgfish, I searched everywhere for the amp connectors and just gave up and went with the $50 ebay / Cayman disassembly solution. I'd be very interested in the input harness VAG part number, as I can't say I'm 100% happy w/ how mine turned out. It's good, but some of the pins just didn't want to come off the circuit board and I ended up having to be a bit more butcher than surgeon.
Also -- very much thank you for this:
It definitely explains some of my struggles in getting sub 40 hz response. That looks to be approximately a -15 dB signal roll off below 40 Hz? Would you agree with that assessment?
I'll have to re-calibrate my expectations on this one.
Also, I had no issues setting my gains -- JL Audio includes a nice how to guide with distortion detected indicators. I realize it's a different manufacturer and product line, but appreciate the challenges from both sides.
I did spend a chunk of time REW and EQ'ing my setup which is on a thread over here: https://rennlist.com/forums/991/1205...s-upgrade.html.
However, I need to revisit my tune as the 2 of 5 Morel Elate Ti MW9's that actually worked took a nose dive. Morel stepped up and replaced them w/ Morel Carbon MW9s, but they definitely have a different response profile and sensitivity. I'd be happy to share some of the particulars of the tune (before and after) if you're interested.
Gotta say, I'm jealous of the Rennspec options on the market. They would have saved me a ton of time and frustration. I'd love to hear your feedback on how they sound and ease of install.
Nice catch on the balanced outputs from the PCR to the amp. I guess I'm lucky that the JL Audio VX800/8i has differential balanced inputs, otherwise I'd have been battling an issue I wouldn't have easily identified.
Like flgfish, I searched everywhere for the amp connectors and just gave up and went with the $50 ebay / Cayman disassembly solution. I'd be very interested in the input harness VAG part number, as I can't say I'm 100% happy w/ how mine turned out. It's good, but some of the pins just didn't want to come off the circuit board and I ended up having to be a bit more butcher than surgeon.
Also -- very much thank you for this:
I'll have to re-calibrate my expectations on this one.
Also, I had no issues setting my gains -- JL Audio includes a nice how to guide with distortion detected indicators. I realize it's a different manufacturer and product line, but appreciate the challenges from both sides.
I did spend a chunk of time REW and EQ'ing my setup which is on a thread over here: https://rennlist.com/forums/991/1205...s-upgrade.html.
However, I need to revisit my tune as the 2 of 5 Morel Elate Ti MW9's that actually worked took a nose dive. Morel stepped up and replaced them w/ Morel Carbon MW9s, but they definitely have a different response profile and sensitivity. I'd be happy to share some of the particulars of the tune (before and after) if you're interested.
Gotta say, I'm jealous of the Rennspec options on the market. They would have saved me a ton of time and frustration. I'd love to hear your feedback on how they sound and ease of install.
01-14-2021, 07:51 AM
#17
Yeah the tilt off makes a lot of sense in a an OEM application especially in the last couple of clicks, but that's easy to dial out with your gain structure to set 0dbfs clip point at say a couple of clicks from top.
I'd say the rolloff is about 8-10db (when comparing 20hz to say 1Khz), it just looks more as there is a bump at the 40 mark due to the HU having +2 bass set.
Unless you have a sub in play, and one with decent volume and low end extension I don't see much issue with the roll off. Reality is regardless of what drivers you put in the door below about 70hz you're into a big ask, moving forward I'll pop a 10" on the rear shelf and probably HPF the doors at 85hz (this is what we use in the studio installs between the nearfield monitors and sub). Idea is to give the MW172 in the door an easier time, less energy into the plastic frame and not suck up as much power by shifting an octave into the sub.
I'd say the rolloff is about 8-10db (when comparing 20hz to say 1Khz), it just looks more as there is a bump at the 40 mark due to the HU having +2 bass set.
Unless you have a sub in play, and one with decent volume and low end extension I don't see much issue with the roll off. Reality is regardless of what drivers you put in the door below about 70hz you're into a big ask, moving forward I'll pop a 10" on the rear shelf and probably HPF the doors at 85hz (this is what we use in the studio installs between the nearfield monitors and sub). Idea is to give the MW172 in the door an easier time, less energy into the plastic frame and not suck up as much power by shifting an octave into the sub.
01-14-2021, 07:59 AM
#18
Ok connectors to replicate the OEM amplifier, so you're zero cut on the car:
Input - 4F0972112 - https://www.ebay.co.uk/itm/Reparatur...-/161841114342
Output - F10 BMW modded - https://technicpnp.com/product/logic...-applications/
The small VAG loom needs a dinky crimp tool - PA-20 -
Can then join the loom nearly (ideally with staggered connections) and wrap in fabric tape.
Input - 4F0972112 - https://www.ebay.co.uk/itm/Reparatur...-/161841114342
Output - F10 BMW modded - https://technicpnp.com/product/logic...-applications/
The small VAG loom needs a dinky crimp tool - PA-20 -
Can then join the loom nearly (ideally with staggered connections) and wrap in fabric tape.
Last edited by Muu83; 01-14-2021 at 08:05 AM. Reason: clarity
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01-16-2021, 04:05 AM
#21
Intermediate
Yeah the tilt off makes a lot of sense in a an OEM application especially in the last couple of clicks, but that's easy to dial out with your gain structure to set 0dbfs clip point at say a couple of clicks from top.
I'd say the rolloff is about 8-10db (when comparing 20hz to say 1Khz), it just looks more as there is a bump at the 40 mark due to the HU having +2 bass set.
Unless you have a sub in play, and one with decent volume and low end extension I don't see much issue with the roll off. Reality is regardless of what drivers you put in the door below about 70hz you're into a big ask, moving forward I'll pop a 10" on the rear shelf and probably HPF the doors at 85hz (this is what we use in the studio installs between the nearfield monitors and sub). Idea is to give the MW172 in the door an easier time, less energy into the plastic frame and not suck up as much power by shifting an octave into the sub.
I'd say the rolloff is about 8-10db (when comparing 20hz to say 1Khz), it just looks more as there is a bump at the 40 mark due to the HU having +2 bass set.
Unless you have a sub in play, and one with decent volume and low end extension I don't see much issue with the roll off. Reality is regardless of what drivers you put in the door below about 70hz you're into a big ask, moving forward I'll pop a 10" on the rear shelf and probably HPF the doors at 85hz (this is what we use in the studio installs between the nearfield monitors and sub). Idea is to give the MW172 in the door an easier time, less energy into the plastic frame and not suck up as much power by shifting an octave into the sub.
Good point, I should have recognized the +2 on the bass would swing the roll off; -8 to -10 dB makes sense in the context.
I don't have a sub and w/ the reduced insulation (and reduced weight) of the GTS, I don't think I'm going to try to add one. Still, without it, I need to get as much low end as I'm able. I can completely see why it would be something desirable to add.
So, I'm willing to ask 9" woofers in the door to get down at least into the 40 Hz range, which the Morels seem to be doing quite well. (except when they were defective) Still they just fell off way faster below 40 Hz than I would have hoped, and this data proves what I was already suspecting. Now recognizing that w/ road noise at highway speeds, much of that low bass extension is lost, it is still there enough to keep things enjoyable.
And thank you for the part numbers, etc. I'm going to pursue reworking my input harness to clean up some of the wire mess in my amp well. I also pursued the 100% reversible / no cuts path.
01-16-2021, 07:13 AM
#22
Three Wheelin'
I know its a lot of work and money, but adding the sub to my GTS was the single biggest improvement in sound I made. It makes the car complete from an audio perspective. These 991's have zero low end and no matter how good the door speakers are, you can never get that deep low end without a sub.
01-16-2021, 12:52 PM
#23
Might be nice and easy to make the whole thing from scratch with a DB25 DSUB connector for the amp. Can make up your own twisted pairs with 2 long lengths and a drill.
01-16-2021, 12:53 PM
#24
I know its a lot of work and money, but adding the sub to my GTS was the single biggest improvement in sound I made. It makes the car complete from an audio perspective. These 991's have zero low end and no matter how good the door speakers are, you can never get that deep low end without a sub.
01-16-2021, 05:25 PM
#25
Intermediate
I know its a lot of work and money, but adding the sub to my GTS was the single biggest improvement in sound I made. It makes the car complete from an audio perspective. These 991's have zero low end and no matter how good the door speakers are, you can never get that deep low end without a sub.
I scrubbed around, but couldn't find anything on your sub install. I'd love to see what you put in place.
01-16-2021, 06:05 PM
#26
I'd measure the pins with some calipers, IIRC it's 1.9mm. Gently tho, very easy to distort the pins.
Personally I couldn't resist making it one neat cable from plug to plug, get rid of the other 6-8 superfluous RCA tails etc. Especially as it's already a redo
Personally I couldn't resist making it one neat cable from plug to plug, get rid of the other 6-8 superfluous RCA tails etc. Especially as it's already a redo
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PJK3 (01-16-2021)
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PJK3 (01-16-2021)
01-16-2021, 06:36 PM
#28
Intermediate
I get the temptation to make one beautiful cable... but you might be over estimating my cable making prowess...
01-16-2021, 06:40 PM
#29
You running fronts and rears to the amp or just fronts?
Plug comes with all 12 pins, you'll be using 5 or 9 depending so you'll have some spare anyway.
DB25s are very easy to solder too. You could reverse engineer the pinout with a simple multimeter on the JL loom.
Plug comes with all 12 pins, you'll be using 5 or 9 depending so you'll have some spare anyway.
DB25s are very easy to solder too. You could reverse engineer the pinout with a simple multimeter on the JL loom.
01-16-2021, 07:39 PM
#30
Intermediate
Fronts and rears for now. The extra rear fill helps overcome my mild (sins of the bass-past) tinnitus. I am not familiar with how the DB25s assemble, but if they're fairly simple soldering, that might not be too bad. I'll do some research. Thanks for the encouragement.