# 2018 sportwagen build



## Adurm (Jan 6, 2019)

Just a quick log of what I'm doing here in my sportwagen with fender audio.
Gear:
Source: Hiby R3 pro saber dap aux out for now.
Dsp: audison bit one
Front door: hertz hv165L
Rear door: focal ps165 (no tweet)
Front tweet: cdt audio unity 7.5 widebands
Sub: image dynamics idq10 v4
Amp for widebands: clarion apa4204 bridged
Amp for doors: image dynamics sq 1400.5.

I decided to run all fresh wires which means going through the molex plugs. I got a depinning tool which helps but it's still a messy tedious task.









I managed to install the rear midbass with some mdf rings (not ideal but should be okay. I got some foam baffles to help keep the moisture off. I didn't like the limited air space they provide plus i needed to get behind them to put nuts on the bolts so i cut them.

















Wires are mostly run. Powering everything from a single 4ga ofc since I'm only pulling about 85 amps. Amp rack is 3/8 scrap mdf carpeted. Abs next time. 









That's it for now. Thanks for looking.


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## OneFastCanuck (Aug 18, 2021)

WOHOO finally a build thread! liking the amp rack. Those Focals are sweet - bet they will sound good! That Audison bit one will be a nice tool for tuning 

Great idea using the Hiby R3 pro saber dap with aux input to the DSP - easiest way to get clean audio signal without going for the expensive ass Zen-V like I decided to do - I only got it because I use a ton of my car's features (ex sensors, GPS as well during road trips, take lots of phone calls, etc.) and wanted to retain 100% of OEM features.


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## Adurm (Jan 6, 2019)

Thank you, it's definitely a learning curve I'm on. Never done an amp rack before. Just kinda wedged stuff in there and hoped for the best. Carpet is stupid for a rack. Not sure how I'm going to secure the wires. I didn't pre drill so i might have to get zip ties with screw holes. Also need to find another 6 inches of wire for my left front door. Hoping i left enough waiting to go through the molex where i can pull some back to the amp. I'm going to secure the rack to the car via L brackets. There's some holes where a trim piece went across the trunk/back seat area. Sub box is a 16 inch concrete form tube that has been coated in resin. I need to cut a few braces for it and make the top piece doing l along with the false floor. Should fit nicely into my full sized spare gti rim.


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## OneFastCanuck (Aug 18, 2021)

you can go with something like I used inside my sub box to secure wires of different sizes - see the link below (this is amazon canada but I am sure you have equivalent kits on .com)



https://www.amazon.ca/gp/product/B08BNJGXRS/ref=ppx_yo_dt_b_asin_title_o08_s00?ie=UTF8&th=1


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## Adurm (Jan 6, 2019)

Oh i like those better than zip. Thanks!


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## JP Fabrication (Feb 20, 2008)

In for another VW build. I need ideas to help me with mine


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## Adurm (Jan 6, 2019)

I'm happy if anything i do helps you with yours. I'll have some pics of the widebands, dsp remote and mostly finished rack shortly. The widebands have proven to be challenging. To which I'll explain with the pics.


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## Adurm (Jan 6, 2019)

More pics.








The above pic is a brace that's covered by trim that i routed wires through. I don't plan on putting the trim back on. I will try to carpet it.








Remote in the cubby. I bent some abs and screwed it to the top of the cubby.








Pod vinyl removable glue didn't hold. Going to make some abs pieces to secure to the triangle window area then use threaded hollow shafts to secure and run wires in.
















Homemade fuse holder for the bit one. Why not?


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## Adurm (Jan 6, 2019)

Amp rack mostly done. I think i need a shorter rca for the clarion. I'll probably put it in the car for fun but can't hook up the speaker wires until i pull a little more from my left wideband and set gains.


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## JP Fabrication (Feb 20, 2008)

Cool. I have a MK4 R32. I still need to find a home for my Bit Ten DRC


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## Adurm (Jan 6, 2019)

I'm pretty sure my drc screen is toast. The dot matrix ones tend to go south. I'm only using mine for power and volume.

I'd love an r32. Don't know what can be modded engine wise. The mk7 2.0t platform are beasts when tuned.


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## Adurm (Jan 6, 2019)

This mornings progress... Amp rack installed. Power and ground hooked up. I wasn't able to run 0ga ground through the brace. Fingers crossed that won't be a problem. Gonna be a while till i post more.


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## OneFastCanuck (Aug 18, 2021)

Looking good! Almost at the listening phase


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## Adurm (Jan 6, 2019)

Forgot to mention, my car has nav which i didn't want to lose total functionality of. I'm leaving all the stock tweeters in place so I'll get some very tinny directions and Bluetooth calls however rare it is someone calls me. Seriously just text. Up next is going to have to be the wideband mount or sub box.


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## bbfoto (Aug 28, 2005)

Adurm said:


> View attachment 319089
> 
> The above pic is a brace that's covered by trim that i routed wires through. I don't plan on putting the trim back on. I will try to carpet it.


Looking good overall! 👍

For the openings/holes in the metal cross member where you have routed your wires through, use some 1/4" diameter corrugated split-loom tubing (wire sheathing tube) to line the perimeter of each opening to form makeshift grommets that will protect the wires.

The slit in the tubing can be pressed over the metal edges of the openings, and if you cut it to the proper length to fit the entire perimeter of each opening it should keep itself in place by friction-fit.









100 Feet 1/4" Split Loom - Tubing Wire Conduit Hose Cover Auto Home Marine Black: Amazon.com: Tools & Home Improvement


100 Feet 1/4" Split Loom - Tubing Wire Conduit Hose Cover Auto Home Marine Black: Amazon.com: Tools & Home Improvement



www.amazon.com














Regarding your DRC's display, are you sure that it is not due to a bad cable? It looks as if that cable has been pinched or damaged just after where it exits the hole in the metal crossmember/brace.

Using a DMM in the Ohm test setting, test the respective contacts between each end of the cable for continuity. These cables are typically simple RJ-11 phone cables which can easily be replaced or re-terminated.

If this cable is damaged, the LCD display in the DRC may not be receiving power even though the other wires in the cable that transmit the data & control signals may still be intact so that the knob and the power, volume, etc still function properly.


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## Adurm (Jan 6, 2019)

Thanks for the tips BB! I never thought of the split loom for that. The drc cable may be a little pinched there. I'll have to check it. I haven't had a chance to really test the drc. I bought the bit used an i think the guy said the screen was bad but for the price i couldn't pass on it. I didnt think ahead when i ran the drc cable. I started in the back with the rj11 end and brought it up behind my center cubby. As you know, the other end is a flat piece. I didn't want to drill a 3/4 inch hole back there so i de pinned it. The lock mechanism on it are little plastic tabs that can only be bent so far before snapping. Well i snapped off the first one, white wire. When i plugged it into the drc, i made sure to hold that one in while inserting the plug. Hopefully it is secure enough. That end might be harder to procure. We'll see once i turn it on. Thanks again for the advice!


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## Adurm (Jan 6, 2019)

So i powered up the system today. As expected the drc screen is blank. But the knob lights up as does the bit one logo on the dsp. Curious if my drc wire is the problem. The white wire was kinda loose. I do need some advice though. My amps aren't turning on. Voltage at the amp remote turn on is only 6v. I have the bit remote out split at the bit going to either amp. That voltage too low? Suggestions?


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## OneFastCanuck (Aug 18, 2021)

What is the voltage coming out of the bit one, without the remote wire connected to amps? Hopefully not an issue with bit one remote out. However would be somewhat easy fix to wire the remote on from somewhere in front of the vehicle I would assume.


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## Adurm (Jan 6, 2019)

I didn't test the bit harness. I'll do it in the am. If it's 12v, then I'm going to try to send a single wire to one amp then from there to the other. My electrical knowledge is minimal. Series, parallel, etc, idk without pictures. Side note, i fiddled with the drc wires with no success. I may need a new one if it's going to make me change input every time i turn it on. I can narrow it down to master and aux. If i could remove master from the software it wouldn't be an issue. At least i have my base crossover and distances set. Hoping to get the bit gains set and make sure I'm not clipping tomorrow. If i figure out that remote wire, I'll be running widebands and rear doors! Gotta say, the fender system sounds better without the sub. Not sure why. Oh and i could remote to the 12v plug in the boot. I worry about turn on and off pops with that though. And i don't want to pull that panel off. I got a 120v inverter built in too.


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## OneFastCanuck (Aug 18, 2021)

Just to rule out your amps and ensure those are all good, you can run a 12v wire direct from the battery to the remote in of the amps to ensure they power on, just a temporary testing wire. Or if you have a spare 12v battery you can use that too.

i ended up using a relay for my remote turn on situation. just to be safe. Hopefully no pops upon start-up.


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## Adurm (Jan 6, 2019)

So i do get 12v on the remote when it feeds one amp. But once i chain from one amp to the other, down to 6 and neither come on. I did read a post about someone having a similar issue and they said there's an internal fuse that someone replaced with a smaller one. I don't recall if it was for a bit or if it was a head unit. I've got an email to elettromedia usa. I'm running the latest firmware so that shouldn't be it. For gain setting sake, I'll just do one at a time til i hear back or tap the 12v in the boot.


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## Adurm (Jan 6, 2019)

So i do get 12v on the remote when it feeds one amp. But once i chain from one amp to the other, down to 6 and neither come on. I did read a post about someone having a similar issue and they said there's an internal fuse that someone replaced with a smaller one. I don't recall if it was for a bit or if it was a head unit. I've got an email to elettromedia usa. I'm running the latest firmware so that shouldn't be it. For gain setting sake, I'll just do one at a time til i hear back or tap the 12v in the boot.


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## Adurm (Jan 6, 2019)

Got impatient. Wanted to feel a little accomplishment in the car. Hooked up the hiby r3 dap. To my dismay, it's only pushing 1v. Website said 2v. My phone does .9v so why have the added equipment? Threw a 1khz tone in there and set the gains on the 5 channel amp. Running widebands and rear doors only. Maxing out at 90w to the wb and 75w to the rear focal. I can't hear the rears which most would say is a good thing. I was hoping for a little mid bass but i do have them crossed at 100hz. Their fs is 83hz i think. I keep telling myself it's just some rear fill, all that work wasn't a waste of time. But these wb on axis dominate the car at the moment. Very pleased with them so far. They're crossed at 600hz. Supposedly can go to 250hz but that's not needed.


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## OneFastCanuck (Aug 18, 2021)

So if you’re getting voltage drop with more than one amp connected to the remote out of DSP, you should definitely do like me and use a relay to turn on al the amps. My dsp even has that written in the manual. Not too complicated, just gotta know which pin on the relay to connect to what.


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## OneFastCanuck (Aug 18, 2021)

Also, for the rear fill, after watching many vids from pssound and other, but mostly PSsound, they actually say that the rear fill helps to add a sort of echo effect and make the space feel larger. If some right they can be really great. For the most part I believe they run rear fill in mono and only above a certain frequency - I’ll have to try and find the video again but was really interesting how Peter from pssound described the functionality of rear fills. Hence why I opted to keep them in my system. Eventually I’ll probably swap the 2-channel for another 4-channel and do an actual 3-way up front. I hope LOL


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## Adurm (Jan 6, 2019)

Maybe i had higher expectations for the rear. They can probably handle a bit more power but I know they're supposed to be barely there. I can't wrap my head around the mono l-r or whatever theory. I don't understand how it helps if everything else is aligned distance wise. Seems counter intuitive. But most people would say that it's the best way to do rear if you're going to. I'll Google the relay.i really don't want to pull that rear panel to get to the 12v plug. I might have to ask for your expertise on it.


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## Adurm (Jan 6, 2019)

Need some advice please. Regarding my remote voltage issue. 2 amps connected to the remote out from the bit result in 6v at each amp terminal. Running from bit just to the ID amp i get 12v. Just bit to clarion i get 6.1v. i don't know if the clarion even turned on. Granted this was early this morning before going to work. I'll have to review ohms law and stuff. Something aint kosher with the clarion.


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## Adurm (Jan 6, 2019)

Scratch that, not 6v but 0.6v. i pulled the old fuses out. They had a good layer of oxidation so i grabbed some shiny new ones. Tested like 0.001 ohm each. Put them in and no luck. I know my troubleshooting has been brief but is the amp dead? Guess I'll test my ground point. Something is causing massive resistance with that clarion.


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## Adurm (Jan 6, 2019)

I'm taking the clarion apart to hunt down the problem. When i pull the terminal end off, I see the markings for power, ground and remote again. I realized that i believe i had the power wire going to remote and remote to power. I think. Could it be so simple? Going to reinstall it in a bit. Hopefully i didn't fry it or the remote from the bit by pulling too many amps.


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## Adurm (Jan 6, 2019)

Yup so that happened. It's amazing what happens when you hook things up correctly.


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## Adurm (Jan 6, 2019)

After my wiring snafu, i set the gains on the clarion. It's rated at 130wpc bridged. I had it to 160w without signs of distortion on my scope. Gotta love class a/b. I backed off the dsp output about 1db to get to a safer 138wpc. If only the id was as clean. Rated at 100wpc. At 90 i can see slight distortion. But the sub channel is clean at 525w. Overall pretty happy.


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## Adurm (Jan 6, 2019)

First impression of the cdt unity 7.5 widebands: overall sound is very good. Not harsh. Playing from 700hz up without any noticable trouble. I have them on axis and the drivers side is rather close to me. I do hear a decrease in db off axis. Its like it's a very narrow dispersion at least that close. Might try to push them all the way to the windshield corners. But snares really pop and vocals sound nice to my ears.


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## Adurm (Jan 6, 2019)

The molex demon strikes again. This time with an airbag warning! I had to re pin 2 connectors. Took one off then put in it's new spot. Then the other. Cleaned inside the plugs to remove plastic bits. Of course the plug in the car side didn't fully click into the metal so it's a bit loose. That could be the problem. I'll investigate tomorrow. I was working on the passenger door so hopefully it's only affecting that side and it's not a fully working or not scenario. Then again maybe it will go away once i drive a bit. I did switch the car on to try to drop the window with the molex unplugged. Duh. Positive note, passenger front speaker is in and working.


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## Adurm (Jan 6, 2019)

None of the electrics work on that door so most likely it's just not fully seated and the power or ground is not happy.


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## Adurm (Jan 6, 2019)

Got it sorted. Seems to be secure. Locks and everything work. Had to use vcds to turn off the airbag fault warning. I should know better than to turn on the car with harnesses unplugged. Hopefully can tackle the drivers side this weekend. I sure do miss a sub though.


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## Adurm (Jan 6, 2019)

After a small hiatus and a random tropical storm this morning, i was able to make some cuts on the sub box false floor. Lumber is on short supply so i used some pine for my under floor, top of box support. Cut a recess for the box to fit into then will glue the box in. Then mount the pine to the false floor. Then carpet. The pine hole is big because the sub box will be off center in the spare tire and i need a little wiggle room. But the sub itself will be center in the floor.


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## Adurm (Jan 6, 2019)

If anyone wants to throw a "WTF is that" out there, i won't be mad. I'm thinking the same thing. It's not as structurally sound as I'd like it. I abandoned the fiberglass step as i really pissed off the Mrs with my last glass project. It was my first time using glass mat and i cut it with scissors to make strips. Glass fibers were everywhere. They made their way into the house and baby girl had a piece on her face. Had to vacuum the garage, driveway and indoors a few times. So this is just 6 coats of resin and some prayers.


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## Adurm (Jan 6, 2019)

Bass progress today in the frigid 40s in FL. Sub and half of the false floor installed. Can't fire it up cause the caulk and adhesive isn't dry. Hopefully have an enjoyable ride to work in the morning. Still have to put some braces under the floor and i think I'll have to notch the part by the back seat corners.


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## Adurm (Jan 6, 2019)

Anyone with bit one experience? I'm running a hi res player through aux into the bit. My input gain is at 2v before i get clipping on a cheap rta. That's with a 1khz sine wave at -.002db. all my music is at the same max level. The bit has input eq 31 bands. I'm assuming my source is flat. Would it be worth a damn to go along each band and eq the input just below clipping? I just did the 1khz. What if the other bands are lower level? My dmm won't get accurate voltages above 12 or 14khz. But the rta will keep up. I don't think it will auto eq the aux input only the master. Maybe I'm putting too much emphasis on getting a flat input?


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## Adurm (Jan 6, 2019)

Well I'm rather underwhelmed. Seems like the sub is only getting 50watts. When i set it up with the laptop and rta and dmm, it should be getting 525w. Tested the terminal on the box and it reads 1.8ohm so my wiring is solid. I had the software maxed out on sub level and master level. My drc remote screen is blank so it's possible the sub level is turned down there. Shoot, could have fade and balance all jacked up too for all i know. Hopefully tomorrow i can get the sub level turned up on the drc if that's the problem. I hope the box isn't flexing so much that it causes that kind of output. I've got 1cu ft which should be close to ideal for the idq10.


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## Adurm (Jan 6, 2019)

Ordered a new drc cable hoping the cable is bad. The drc screen lights up but it has no pixels. I'll return it if the cable doesn't fix it. I turned the sub volume up on the drc today with little success. I get low bass but nothing with authority in the higher sub region. Amp crossover is wide open so hopefully it's in the software. Weather sucks now so I'll try to see what's up in the morning. I feel like i should start these posts with "dear diary"


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## Adurm (Jan 6, 2019)

I had the sub crossed at 100hz Butterworth 12db. Changed to LR 100gz 12db and it sounds better but still puny in the higher range. I'm going to have to recheck my voltage across more than just 40hz. I suspect there's a bump at 40 then drop off. I'll open up the crossover and make some adjustments. Might even remount the sub. I have it sitting on the carpet so I don't trust the seal.


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## Adurm (Jan 6, 2019)

Rechecked voltages across all the sub range with the crossover on full. There was a very small bump up at 35 but smooth everywhere else. Also found the sub amp gain was down a click so it was only getting about 450w. Turned it up then backed off the dsp level 1db to get it at 525 upwards to 550. Also pushed the crossover up to 120 which is way higher than i want but we'll see how that sounds. Re mounted the sub to remove the carpet under the frame and made a ccf gasket. In the process, i stripped at least half the screw holes. Sigh. I'll get some larger diameter screws next week. Also will report back about the sound. My umik is now shipping the first week of March. Another sigh.


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## Adurm (Jan 6, 2019)

To update the stalled progress... I've come to terms that my sub box isn't going to cut it. Probably not rigid enough. It's really lacking in the 80hz ish range. Air space is good but something isn't right. Going to build a real box from 3/4 mdf. Umik came in through someone on the forum. Waiting for ball joints from Germany for the pods. Fabbed up one abs little triangle window mount. Going to bridge the image dynamics 5 channel to the front doors. Ditch the rears. Or could bridge it to a pair of 6.5 subs, sub channel to the 10 or upgrade to a 12 and get a bigger 4 channel. We'll see how that progresses. 0ga power wire coming. Basically new build. Sorry no pics and lots of words.


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## Adurm (Jan 6, 2019)

Got some 0ga to run. Pulled the rears and put the factory ones back in. Didn't have the right size screws and my rivet gun is too bulky to get close to the mounting ring. Ended up using some zip ties run through the holes. Seems secure enough for the next person lol sorry. Got some hertz 165xl to replace the front hertz. 8mm xmax vs 4mm and more power handling? Why not. New audison remote looks good. Need to fab up a better mount and make it nice. Next post will have pics.


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## Adurm (Jan 6, 2019)

Scored a set of hertz hv 165 xl from a member here and replaced my hertz hv 165L up front. These new ones handle 125w each vs 100 for the old. Xmax is 8mm vs 4mm. Hoping to feed them 150w from 80 to 500hz. That will take me figuring out how to send signal from the dsp to the 5 channel and bridge it. I don't want to use splitters so I'm going to have channel 5 and 6 be identical signals which will go to amp front left and rear left. Same with 3 and 4 but go front right and rear right. Front right pos and rear right neg is one speaker. Then front left and rear left to the other.


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## Adurm (Jan 6, 2019)

Got the bit set for the bridge. Amp tested. Clean signal bridged at the moment. Pushing 150 to 160w each. Couldn't get them exactly the same voltage. I think i can turn down one of the paired outs .5 db lower and get the two out puts more even but i don't know if that's a no no.


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## Adurm (Jan 6, 2019)

Haven't been happy with my pods having to tape them to the dash. Ordered some used a pillars to mount to. Don't like nav and calls coming out of the front stock tweeters. Going to recode the radio for speaker out and use the factory deck. Don't like the half assed sub tube i did so I'm making a real mdf box for a dayton ho12 with passive radiator. Pics when it gets some traction.


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## Jheitt142 (Dec 7, 2011)

I've done a lot with sonotube, if you dont want the glass mess just milkshake the bejesus out of it. works a treat for me 

I got crazy one time and bought the next size down and used it as its meant to be used, put one tube in the other and filled the space between them with concrete. talk about solid!


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## Adurm (Jan 6, 2019)

I wish I'd known about the milk shake before. I should have researched better before trying something I've never done before. With a little luck this pr build will make me happy.


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## Adurm (Jan 6, 2019)

Big thanks to @jrobie79 and @Jehay1 for getting stage II together for me. Box plans were perfection. I did not however allow for box carpet in my measuring so it's really snug in there. Probably don't need the strap but it's there just in case this 1.8t gets wild. Sub and pr look good. Still need to fire it up but i expect quality bass which i haven't had since 3 jl 10w6 back in 99.


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## Adurm (Jan 6, 2019)

Oddly enough, i get no sound from the sub. Terminal on the box reads 2ohm. Continuity on the amp to sub wires. Dsp is not muted. Sub voice coils read 3.8 or so each before installing it. I didn't take the sub out of the box to triple check the wiring but if it's 2 at the terminal then that should be good. Suggestions?


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## Adurm (Jan 6, 2019)

For those who read the last post, i found my problems...i thought i set up the dsp and amp gain for the sub weeks before the box went it. Turns out it was only pushing 24v. Bumped that up to 33v, close as i could get to my target of 34.6 or 600w without cranking the gain up another click and getting distortion. Additionally i wired the sub in some stupid config where the leads from the box terminal each went to a positive coil. I'm surprised i didn't kill it. Lesson here, make sure there's plenty of light when wiring especially for the red/green color blind community. The red looked a lot like black.


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## Adurm (Jan 6, 2019)

Still super disappointed. I had left and right sub out from the bit one. Figured that might be a problem so i did the single sub out through a Y Rca to the amp. Made a bit of a difference. Re did the gains of course... Again. Terminal at the box reads 1.9ohm. bass is still not what i was hoping for from a 12 and passive radiator. The pr barely moves. Nor does my rear view mirror. A known indicator of bass power. Anything above 50hz is puny at best. Similar issue with the previous sub. Source is either my phone or dap so the signal should be damn near flat. Before i buy a new dsp, anyone have a suggestion?


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## jrobie79 (Mar 27, 2008)

Any luck?


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## Adurm (Jan 6, 2019)

Will know later today. What i did yesterday was pull the poly fill out as i remember stuffing it in the bracing which may have impeded pressure to the pr. Also found the same voltage on the inside of the box terminal as at the amp output. So the amazon terminal cup is ok. I didn't trust my sub wiring as i used it on my previous sub which had the same shortcomings. So i made a new piece of wire and triple checked dvc parallel diagrams. Fingers crossed.


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## Adurm (Jan 6, 2019)

Nope not better enough for me. Thinking the bit one is the weak link.


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## Jheitt142 (Dec 7, 2011)

a single 12 and a pr should produce plenty of output in a wagon. do what you can to try to just test without the bit one in line.


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## Adurm (Jan 6, 2019)

I ended up getting a zapco dsp z8 iv ii. Much newer tech and higher clean output voltage. However my problem persists. Low bass like 50hz is fairly solid and tactile. Anything above is non existent. Bumped the crossover up to 120hz with no luck. My dap puts out a steady 2.04v from 20hz to about 4khz (meter can't keep up with the cycles) so I'm confident that's not the issue. Could a not so great ground do this? It's 0ga ofc to a ground down seatbelt bolt. I plan to test the rca out from the dsp and amp sub out from 20hz to 120hz to make sure that tapers accordingly. And ohm that amp ground. Probably ground test first. I forget how to do that. One lead on neg terminal of amp and the other at the bolt?


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## jrobie79 (Mar 27, 2008)

Adurm said:


> One lead on neg terminal of amp and the other at the bolt?


That's what I would do, then just because do it again one from the bolt back to the negative terminal on the battery, the lower the resistance the better obviously


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## Adurm (Jan 6, 2019)

Thank you, I'll give it a shot and report back.


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## Adurm (Jan 6, 2019)

Amp ground to ground bolt is .01 ohm. Opened up the crossover and tested sub frequency voltage at the sub terminal and got a pretty steady 34.4v from 20 to 125hz. Crossover from 125 lp i was getting 25v at 50hz. The amp crossover is not defeatable but is turned up to the max of 300hz. I wonder if the two crossovers are interfering. I think I'm going to try full range on the dsp but use the amp crossover. If that fixes it then i have to do the same to the mids.


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## jrobie79 (Mar 27, 2008)

Maybe the RCA's are compromised somewhere?


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## Adurm (Jan 6, 2019)

Not a bad suggestion. I'll test each pin for resistance. I do think i have only 14ga going to the sub which i did test at the box end of the wire. Maybe 14ga ofc is too small. I know i have some 12ga floating around. I'll redo the inside wiring if needed as well.

Something i can't figure out is how to program the zapco to only use 5 channel out. It wants to push to 2 subs and rear or mid front. I can mute the rears and match the distance to the farthest away driver so it doesn't mess with the t/a but i can't just choose one sub. Granted, the subs are using combined right and left input so it should push a mono signal.


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## Adurm (Jan 6, 2019)

So 12ga ofc from the amp to the sub didn't do the trick. Going to defeat the zapco xover and use the amp tomorrow morning. If that's no good then I'm going to plug half my box to bring the airspace down to about .75. it's 1.6 at the moment using the passive radiator


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## Slave2myXJ (Dec 18, 2021)

Didn't read the whole thread, but I believe you have a DVC sub. Have you triple checked that the polarity is the same on both coils? If not, they'll counter-act each other and you'll get next to no output.


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## Adurm (Jan 6, 2019)

Can't blame you for not reading the whole thing. It's a bit of mess. I've never considered the terminals to be mislabelled. I'm not sure how to check that. I tested each side before the install and i believe they read around 3.8ohms. But that doesn't exclude polarity problems. The terminal on the box reads 2ohm in my meter. I'm thoroughly confused but very close to checking everything off the list.


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## Adurm (Jan 6, 2019)

Bigger wire and using amp crossover didn't work. The thing is, i have decent low bass but upper sub notes are lacking. I'm suspecting too big a box. I believe it modeled well at 1.6 cu. The Dayton 12 wants 1.37cu ported. When i called parts express (who answered within minutes) they said I'd need 2cu and 2 passive radiators. I'm going to check the coils next and if they are good then I'm walling off the box to about. .7cu. specs are .49 sealed. If that shows improvement, then I'll have to move that wall to get the 1.37 cu suggested ported. If that sucks too then I'll redo my spare tire tube to .5cu and ditch the pr. Ugh.


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## Adurm (Jan 6, 2019)

Slight improvement with a smaller sealed box. I still can't figure out what's wrong. Pushing test tones through the dsp and amp with the crossover off, i get a consistent 35v from 25hz to 150hz (unloaded). I don't know how that varies with the sub connected. Sub is wired correctly for 2 ohm load, vc seem to be okay. I don't have a spare sub around to test but i was having the same problem before this sub. I think the only thing i haven't changed is the amp.


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## Adurm (Jan 6, 2019)

Ugh. Tested 2 aux cables. Same voltage through both. Same voltage out from dsp using both aux. Same voltage getting to the box. I had the issue with my previous sub in an upward facing box and different dsp. Source and aux cable were the same. I'm at a loss.


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## Flygts (Aug 17, 2021)

I would try swapping out the amplifier


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## Adurm (Jan 6, 2019)

Not a bad idea. I've been eyeing a new 5 channel and getting rid of a couple 4 channels i have. I currently don't have anything powerful enough to test like i want. I'm not savvy enough to know if the current amp is doing something silly when it's pushing power to a load. Guess your idea is the only way I'll know. I appreciate your suggestion.


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## Black Rain (Feb 27, 2011)

Adurm..

I am Central Floridian VW guy. Read thru most of this build and you have been thru hell with all these troubles you have encountered. Good thing is that they have become learned lessons.

Keep it up, you will prevail.

Sent from my SM-S906U using Tapatalk


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## Adurm (Jan 6, 2019)

Thanks boss. The build log became more and more of a plea for help as it went on. Hate to say it but I've sold most of the gear, at least all the desirable stuff. Currently waiting for a cheap loc to link into this killer little alliance 4 channel amp to bridge to an 8 in the spare tire. I will not disclose the sub on this site or i might be banned. Let's just say it cost less than 40 bucks. The amp goes into protect with high level to rca that i made. I can only get as low as 5v on the sub out wires. The fender sub gets about 35w per coil from what i measured.

I still don't know what was wrong with the subs previously. Amps, boxes, signals? I tried multiple variations. One thing i never tested was the alternator. Still love the car though. 

Thanks for reading and the encouragement. I'll be back at this stuff sometime soon.


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## Black Rain (Feb 27, 2011)

Your welcome.... Look forward to your return. Keep your head up.

Sent from my SM-S906U using Tapatalk


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