if been playing around with my fronts and swaped my USD piezo drivers with some titanium diagphram ones (again ) but this time everythings active with a amp for the mids and one for the horns.

there is always hiss in the horns, regardless of gain settings' its not much but it is noticable and i assume its because of there high sensitivity, even if i disconected the eq and deck they seem naturally noisy.

i never noticed it when i had them in there before but it was awhile ago, but is it normal for high sensitivity drivers (105-110db)? and is there any way around it?

is that why many years ago there was such devices as 'crystal line conditioners' and niose gates being used with high end compression drivers.....i remember them cause i almost bought some

the motors a actually 2" RCF TW-101's run from a HX-D2 and a pair of crossfire cfa 602's all run through a audiocontrol DQT (which i hate by the way)

Probably a silly questions, but have you set your gains? It could be coming through the amp, seems odd that the horns would make a noise by themselves.

bmwturbo, he said there is his regardless of the gain settings

tuneman, where is your DC-DC converter sitting for the HX-D2? I know from experience with mine (and reading about the US guys and the DRZ9255) if the converter is too close to the head unit, you can get noise that doesn't seem to be related too much to amp gain.

Hmmm... Been a while since I had horns in my car. Used Veritas cast aluminium ones back in 1997/8. Yep, their ultra high sensitivity means they'll show up your system's noise floor very easily. If all else fails I'd suggest trialing an different amplifier for them other than the CFA602. These are a decent old amplifier (I remember reviewing this thing on the test bench and being amazed at its power for the money back then... ) but it is possible that its noise floor is what's being shown up here. Even if the HXD2 has a high SN ratio the system will only offer an SN ratio of the worst component in the chain - and that would be the CFA602. If a mate has a different amplifier (even bread and butter Sony amps are over 100dB SN ratio these days) maybe it would be worth a try to see if it makes an improvement.

If you unplug the RCAs from the horn amp and plug in shorting plugs (ground to signal) is the noise still there?

Phil

if the noise is not going up/down with gain adjustment, then it is in the output stages of the amplifier, or the speaker wires.

most likely the amplifier noise.

The speaker wires?

I remember Damon's Rodeo with the horns, I so loved that mini-truck. The 8's in the doors was the one thing that stuck in my mind the most. I loved the intergration on them.

MTX Thundercasts, I believe. They were awesome.

Wow, you've got quite a memory there TEGBOY.

The Rodeo was used for the bulk of my reviews during the most prolific period of car audio testing for me, so remembering what was in it is more a matter of 'which day was that?'.

For a while I had the horns and, yes MTX Thundercast 8-inch subwoofers that, frankly, weren't suited to small sealed boxes. The Rodeo had small quarter glass window in the front of each door so I had space below these for a sealed enclosure made from MDF, fibreglass and foam for sealing. It never really worked as well as I would have hoped, but this is more to do with the fact that low Qts 8-inch drivers were so scarce back then. What else? Clarion DRX9255 for the source, and for while at least MTX Blue Thunder amplifiers and six Blue Thunder 10-inch subwoofer in a wall behind the front seats. GO THE WALL!

i'll definately try another amp, as my 602's are getting on a bit i guess, they are 98 and 99 models(retro )but it is way convenient as i have 6 of them just lying around.
although they do have a slight turn on pop!

i ran new wires. and a good thing to as i found 5 joins in each side in the old ones

and Timm3h the dc-dc converter is under the seat

hey phil what do the shorting leads do?

i would suggest(as aTest) making sure the amp is not connected (metal wise) to the body of the car, also same with the head unit.So if u do that for a test and do the amp first and if the noise doesnt go then remove the HU(touching metal) and any other metal casing equipment u have.

Stange but true my friend.

I've heard of cases in VEs where the speaker wires have picked up noise......

Phil

yes very true in VEs. ur supose to run new speaker wires as the wire pickes up noises

What kind of crazy stuff is going on in VEs that would induce noise onto a high voltage AC signal? Wow...

What about the 3-way MB Quarts, the Cyclone. I remember all these being in the Rodeo at some stage. Mainly from reading Hot4's. It was my bible when I first became interested in cars. I still read the older articles at times, and wish the good old days of car audio would come back..... gah I am showing my age now.

Don't then start me on the Charade you had or the 200

-clint

I wouldn't have beleived either.

Crossover location is another big issue.

Phil



If you connect the siginal to ground on the RCA inputs, you can isolate the noise to the amp itself.

Phil



If you connect the siginal to ground on the RCA inputs, you can isolate the noise to the amp itself.

Phil

I had noise coming into the speaker wires on the drivers side of the BMW. The strange thing is it only occurred when i had the amp connected however.

I literally pulled the speaker wire back to the rear seat and the noise was gone with the tweeter connected. Ran it back down the drivers side of the car and the noise would come back. I'm still scratching my head.

Same deal with the VEs. Move the speaker cable 30cm and the noise goes. I never would have thought it possible either.

Phil

sometimes the noise induced in the speaker cable 'feeds back' into the amp, and gets amplified (something about transistors being diodes and demodulating RF).

I actually have a Kenwood amp here that plays the local radio station through a 10" woofer, even with the LP filter turned on. It's noise induced into the output stage from the speaker wires, and feeding into the driver stage, where it gets amplified. a 100pf ceramic capacitor across the speaker terminals fixes it right up.

i did some tests and it appears to be the amp, with all gains on nothing it is minimal and isn't noticable when driving so i might just put up with it, i tryed 3 more and they all do it.
there was a small ground loop problem that the ground lift jumpers on the dqt fixed,....im to slack to shift the earth:)

whats more important is the fact that i now have the cleanest and blisteringly loudest front end to date in my car!! its just insane with any kind dance music.....you duck for cover with the dynamics! ahh horns

VE Commodores are a headache full stop IMO, noise, voltage issues, and poor build quality/flimsy interior panels...

no shizzle?!

i'd put that up on eBay! thats awesome!