Decided that it was worth investing in an amp and components for my Octavia and need some assistance.

Having installed a Focal Fpp2100 and focal 165 v30 comps using the high level input option on the amp I am getting a fair amount of hiss and 'electrical' noise from the tweeters.

I must have reviewed a hundred articles on hiss and noise but still slightly confused!

Does anyone have experience of adding an amp to a stock Headunit (Amundsen +) with the same issue. The amp is located under the front passenger seat.

The noise is reduced but still there even if I turn the gains all the way counterclockwise and the Headunit volume is 0 with car not running.

Any advice would be welcome

Probably telling you how to suck eggs but here's my 2 pence.

I am in the process of building up the ‘bits’ for my car install but this will be my 8^th personal install I have done. With this in mind I have experience of ICE installs but not with Octa II…. yet

Check your earth connection is clean and is not got any paint residue in the connection.

If possible, try changing it. Not sure what’s available under the seats so I can’t advise on what and where.

Check your power cable aren’t running in line with any of the signal wires.

This includes the remote on power wire. Shouldn’t be an issue really with the high level inputs so I’m told. All of my previous installs have been with replacement head units and a couple of Car PC's so this will be my first OEM integration.

Check you are running the right gauge cabling for power.

From looking quickly, the Fpp2100 is rated max 2 x 140W at 2 Ohms with a 25A fuse so 4 gauge cable maybe over kill but 8 gauge might not be enough. The only reason I mention this is the fact I have seen 4 gauge cable where the overall diameter is the same but the cores are massively different. One a recent job I looked at for a mate, he was using supposed 4 gauge cable that had a core that was barely over 8 gauge. Anyway this probably has nothing to do with your issue (sorry side tracking).

Is it definitely affecting both channels, left and right?

Try setting up your install again

Set the Gain on the amp right down, set the stereo to about 65-75% volume and bring up the gain.

If this starts hissing and you still have ‘room’ on the gain, try again but at 50% volume. etc. etc.

Keep going until you lose the hiss.

If it’s still happening, try the original speakers. Make sure you lower the gain before turning on the system. If so, it’s not the speakers so it could be the AMP, wiring, stereo or a combination.

What do you have the crossover on the Amp set to, HPF, FULL or LPF? Try changing from FULL if that is what it is set to. DO NOT CHANGE THIS SWITCH WITH THE AMP ON! I would check with the AMP retailer for their recommendations with the Amp / Speaker combo you have.

Do you have an option to lower the output on the tweeter? This will probably only apply to components where you can wire the tweeter on the crossovers +- 3Db. This option is available on Alpine and Infinity crossovers, I’m afraid I don’t know Focal kit at all. It’s a bit of a cop out but may help to lessen the sound a bit.

If you have a spare or old stereo with RCA outs you can try this. This will partly rule out the Amp. I say partly as the issue could be that the high level inputs are not as good as RCA inputs. Leaving just the wiring and the head unit itself.

Finally and this is the option I am going down. You could get a dedicated converter from High level to RCA or Line Output Converter. Decent ones aren’t cheap but I have heard the difference they can make.

I have gone for an Audio Control LC6 which will take up to 3 high level input pairs and output up to 3 RCA pairs.

Reviews on an American site

http://www.sonicelectronix.com/item_6359_AudioControl-LC6i-Gray-LC6.html (4.8 / 5.0)

And can be purchased from any good audio supplier. Got mine from Car Audio Security.

http://caraudiosecurity.com/shop/product/products_id/3867.html

They do a 2 channel version as well but it’s not that much cheaper than the LC6. I notice you are in London, If you are west London, I strongly recommend popping in to them for advice. They have your Amp, so might know exactly how to help. They also seem to do an lot of VAG cars.

As mentioned above, the first thing id do it look into your earth. This is a very common problem when getting interference such as alternator wine.

The earth needs to use the same size cable as power (remember its a circuit so all needs to be the same). You much be using a point where its connected to bare metal, NOT through paint.

Also, using the high level inputs is an ok solution but if you must use the oem headunit then getting hold of a processor makes it much better and gives you much more control.

Aswell as audiocontrol you can get processors from Mosconi, JBL, JL and Audison

Thanks for your replies. Appreciated.

tweeters were set to -3 during the install as they seemed to distort when turned up and set at 0. The filter was set to full but i moved high pass and set quite low (about 60-70hz) as well as adjusting the gains.

Having spent some time with them now, running them in, I am really pleased with the overall sound. Stereo imagery and mid bass is great - I think having tweeters set as they are do slightly dull the treble but having compared the sound to my kit in home the difference is minimal and suits my taste and given the tweeter location in the Octavia mkII it's probably for the best.

So as soon as I get some time I must actually see and check the earth location to see if its clean

Next idea, mentioned above, will be to see if i can get hold of another unit with rcas and see if it makes a difference.

I wonder if any audio suppliers would be willing to actually try something like Lc6 with my car without charging or me making any commitments - worth making some calls me thinks.

Forgot one question - in regards to keeping the power cable and speaker cable. So literally I should expect the power down one side of footwell and speaker cable on the other side?

Ideally any power (including the 12v+ trigger) should be kept away from RCA leads. As I said, the install I am working on at the moment will be my first attempt with a non RCA source so I have no actual experience with high level setups and interference. It makes sense to me to use the same method that I would use with RCA's. People I have spoken to about running the headunit speaker outs to the LC6 said I could use network cable if wanted to (I don't and won't though). This would suggest to me that high level input doesn't suffer from interference like RCA's do.

With this in mind I found my first install, which was done professionally for me, quite strange. The RCA leads they used actually had the 12v+ trigger moulded into and running between the RCA pairs. Dunno if the installer had been lazy, used the cables incorrectly or what but I replaced them when I pulled the kit out to go into my replacement car.

I can't find it now but there is a post on here where the installer put all the wiring down one side and he was pushing several 1000 watts. He didn't mention any interference. With what he was doing, I think he would have noticed a hiss.

Found it!

http://www.briskoda.net/forums/topic/179137-project-little-white/page__st__30__hl__amp#entry2850812

Check out post #46, Mad....

Found it!

http://www.briskoda.net/forums/topic/179137-project-little-white/page__st__30__hl__amp#entry2850812

Check out post #46, Mad....

Where will he put the pram and shopping?!

I would be really interested to see how you get on - it will take me a while to play with mine

Matt must be deaf by now the power he runs - LOL

that was his small project too. Project "big black" was the other project. A LWB shogun with 8 12" ground zero subs and about 25000 watts of power (i think). With the shogun Im pretty sure he came 2nd in the world in 149.9 Bassrace a couple years back

Got a test bed wired up in the boot ready to go but I can't figure out which wire on the back of the Columbus to tap into to trigger the amps. Spent ages looking thought the forums but can't find squat.

Can anyone tell me which PIN number it should be?

Could you not use a switched live out of the fusebox?

Thanks for the reply.

Funnily enough I found a post from yourself suggesting this elsewhere. I have now got the fuse socket wire from my local VAG spares supplier, dusted off the trusty multimeter and will be playing with the fusebox tonight.

Do you have a recommended rating for a fuse?

As a trigger line I would go for the smallest you can possibly find (1A?). I've got 1A on my DRL trigger, not blown so far.

To me, the fuse-box has always been the easiest place to run a line from, especially if it's on a spare. You know there's nothing else on it. Makes any (hopefully not needed) diagnostics much easier.

Thanks for all your help RainbowFire.

All wired up tested ok. Only had a 5A fuse kicking about so I will swap this ASAP.

Others may find this useful

http://www.golfmkv.c...ead.php?t=62584

Explains how to add a new fuse.

The only issue I have had is that my Columbus now only has balance controls, the fader option has disappeared. This seems to be quite a common issue with our fellow Vdub boys and girls and I have found to following info but have yet to try it.

https://www.google.c...iw=1024&bih=672

Generic google search

http://vwnavi.com/vo...-usa-model.html

A US post about the same issue

http://wiki.ross-tec...ystem_(Columbus)

Ross-techs Wiki page on using VCDS

I am planning to try the later and will update on my findings tomorrow hopefully. I am planning to look at Byte 01 and 02 with the idea of changing 02's value to 04 and / or tinkering with 01's value depending on what is currently set to but 05 seems to be a value that pops up several times during my searches.

You know what, I remember the good old days with the mk1 octavia where it was just a swap and drop for a stereo / amp upgrade. Hell I even had a car PC in mine for a while. Even with all the faffing with that ultimately doomed project, things seemed soo much simpler.

Still I'm nearly there, just got

front / rear door speakers

2 x 12"subs with custom box

Turn the test bed into the final setup with the AMPs and associated gubbins to hidden in the sides of the boot space.

are you using an actual processor to run your amps?

I'm using one of these

http://www.audiocontrol.com/t34/17612/14160/OEM-Integration/EQS-Six-Channel-Trunk-Mount-Equalizer.html

Where will he put the pram and shopping?!

I would be really interested to see how you get on - it will take me a while to play with mine

Hi G Zip VRS,

As above, got the kit working now and happy ish with the results. The setups good but I have had a few issues that I was unprepared for.

Being ‘old school’, the CanBus related issues, really annoyed me. My fault for lack of prep work.

The biggest issue I had was functions disappearing from the MDI or headunit every time I got a step closer. The MDI features seemed to re-appear after driving round the block and then re-checking.

The headunit is missing front/rear fader controls, balance is still there which was a bit frightening at first. Looks like this is a job for the VCDS.

I have however absolutely no noise or hissing, which I am really pleased about. My Amp is in the boot and I am using a dedicated earth point under the passenger side parcel shelf trim.

I have an essay coming together for all the issues with trim etc but I don’t want to ‘totally’ hijack your thread so I will put it in a new one.

I'm using one of these

http://www.audiocont...-Equalizer.html

that'l be a yes then lol

That is a problem with using oem units. You loose certain functions. Unless someone makes a processor designed to integrate with that specific unit like the columbus you wont get all your functions.

Its just something you have to put up with unfortunately

Just changed the coding for the system as per Ross-Tech Wiki and hurray, my Fader's back.

FYI

Electronics 1

37 - Navigation

Coding - 07

current coding

00000402000100810000 OLD

00050402040100810000 NEW

This changed the Byte 1 from

00 (Sound system not installed)

to

05 (Dynaudio Sound System)

it also seemed to change Byte 4 from

00 (Not coded)

to

04 (Speaker Monitoring: Front and Read active)

I'm not super keen on playing with these values just in case something goes wrong but I do back everything up first. If however anyone knows a good reason (like my Columbus will burst into flames) NOT to change this, please let me know

The audison amp I have in our fabia uses the speaker level inputs from the factory head units as the signal cables and even uses them as the trigger so no remote switch on is required. If you google audison line level converters they do a stand alone item for about £80 that takes your speaker wires in and converts then to Photos and a trigger a wire. This will provide a stable remote.

If you use a trigger which is not connected to the stereo then you will get a 'thump' through the speakers when switching the car on and off and risk blowing the remote trigger circuit of the amp.

The audison amp I have in our fabia uses the speaker level inputs from the factory head units as the signal cables and even uses them as the trigger so no remote switch on is required. If you google audison line level converters they do a stand alone item for about £80 that takes your speaker wires in and converts then to Photos and a trigger a wire. This will provide a stable remote.

If you use a trigger which is not connected to the stereo then you will get a 'thump' through the speakers when switching the car on and off and risk blowing the remote trigger circuit of the amp.

Try this bit of kit:

http://www.caraudiodirect.co.uk/con-sli2-connection-sli2-2-channel-line-level-convertor.html

Cheaper than the Audison one but does the same. There is a 4 channel version as well.

Thanks Nemtex

I think that confirm that I need to get my hands dirty and check everything again.

Look forward to reading about your other 'discoveries' during your install

Hello mate, I have the same problem...did you manage to resolve your noise issue ?

 

D