salimshah

Thank you tomv for your patience and taking time to answer questions. I think now things are gelling in my mind ...

SIK issue: It is the soft molded plastic and lack of voltage regulator built in. Fit finish are fine. I was not trying to drag their name in mud.

Simple Mod: [again I am not trying to trivialize the mod or say there is no work involved, Simple is electrically easier to achieve. If th results are acceptable why not.]

The fact is Lexus system requires differential inpit L+/L- and R+/R- input swings. The head unit electrically does a difference of the signals ..

(L+) - (L-) => 2L [The 2 in 2L is a gain factor and inside the hu it gets adjusted further]

Now in simple mod, the Aux signal is fed as gnd (reference as 0)
(Laux+) - (0) => Laux

As long as Laux can be made equal or approaches 2L (Lexus standard), we have a working solution. {volume at head uniit will sound the same as you Aux source}

Kudos goes to the person who tested that by by connectting "gnd" [not just the signal at zero] but the actual chasis gnd, no bad things happen to the hu. A safer soltion woulfd have been an isolation tranformer.

A resonable bit of amplification is needed, and pre-amp out levels [Laux = 1v] is low as compared to the needed 2L level. Line out (amplified) signal seems to work.




Salim

russman16

Tom,

Where did you hookup the power to the switch? Did you get that from the cigarette lighter like the IS300 install instructions?

tomv

In my installation, I tapped into the 12V power that is fed into the CD changer.

russman16

Tom,

Thanks,

We found a 12V supply in that same bundle as well. Installation is complete now on my wife's 2001 RX300, sounds fantastic! Thanks for all our your postings on this topic.

Oqsy

thanks for the fantastic writeup on a great topic. i have just done a similar setup using radio shack parts (no relay, just a straight splice with a terminal strip).

I have some questions....

Has anyone noticed a lowered volume in the ouput of the ipod with this method over a tape adapter or a lowering in volume in comparison to the cd changer? I have to crank my ipod almost all the way up to get close to the volume i used to have, or i have to turn the head unit volume up an extra 1/4 turn beyond my old "comfort level". Is this part of the deal? would adding a switch so that the signal is either from the cd changer or the ipod help boost the signal? should i just crank it and forget it? not a huge deal, but just wanted to make sure it wasn't indicative of a larger problem.

once again, fantastic work and thanks for the brilliant thread. I plan on taking pictures of my approach (almost identical, but I found a novel way of tucking cables and getting the 1/8" jack and the ipod power charger into the center console without any mess) and posting them in this thread.

Oqsy

Squareback

Yes it is a tad bit lower, as the Ipod output voltage is lower than what the Stock head unit puts out. You can either live with it, as I have been doing for six months by cranking up the Ipod to 95% and turning up the HU slightly.

If it really bothers you, you can get a Belkin Auto Kit (or similar device) that has a mini amp, and that way you can boost the signal coming from your ipod prior to it getting to your head unit. I just bought one to test out, they have them on ebay for less than $20 shipped.

Glad it worked out, let see your pics. I would be interested in seeing your substitute for the relay.

Oqsy

wouldn't adding another amp inline just increase the noise and distortion levels? i was thinking that i'd read that every powered amp on each signal adds its own bit of noise, and even if you keep each amps gain low, in the end when you turn up the final signal, all that noise still gets amplified. plus, I have no problems with belkin, but I have some doubts in their ability to build a high quality low noise amp. The big point in this install for me was getting better sound quality than through the tape deck (which was VERY successful), with the added bonus of having a cleaner looking vehicle and a handy place to keep my ipod. right now there's nothing between the ipod and the head unit except copper wire and the terminal nuts, and when the ipod is paused and the volume on the head unit is turned all the way up, the speakers are nearly silent, which is amazing... almost *NO* noise. Anyway, I've severely digressed. If I get another positive review or two on the belkin i'll at least give it a shot.

the part i used in the place of the relay is a white plastic "european style" terminal strip from radio shack. I'm pretty sure it had 8 pairs of connectors, but I used my wire cutters to snap it off into pairs of 2 so that each channel had it's own terminal (much less confusing if I need to go back and add/change something or just return it to factory wiring) I'll find the package and the part number, and post the pictures as soon as I buy a new digital camera (last one was lost.. still sick to my stomach thinking about it). I also used a pair of female RCA jacks and a 6' male RCA jack to 1/8" extension cable, also from radio shack.

salimshah

If you look through my posts here and in electronics/audio CL forum, I have discussed the need for amplification.

I am not a fan of line level outputs (conntrolled by volume control) but that might get you closer.

Salim

Oqsy

another bit of info... i noticed today that with my iPod paused but connected, the CD volume is drastically lowered, but simply unplug the iPod from the 1/8" jack and the volume ramps up considerably. Not a big deal since i can easily unplug the 1/8" jack any time i want to listen to the CD changer, but I wonder if similarly cutting the circuit to the CD changer (switches) would have a similar effect on iPod volume. i suppose the scientific approach is to remove the glove box again and d/c the audio connection to the changer and see if the iPod volume increases.


salim:
when you say "need" for amplification, does that imply that for one reason or another one can't do without it? i'm content to just up my head unit volume to compensate for the time being as long as there are no inherent dangers of damaging any components with my current setup... the only problem comes when switching to AM/FM or Tape, as the volume is now ungodly loud, but I can get used to turning it down before changing sources...
i saw your dual op amp rig in another thread. which stereo system was it designed for? is it compatible with a 1999 rx 300? what are the dimensions of your unit, and do you build them to sell? if not i'd be very interested in more pics and specs if you don't mind (pm is fine if we're getting off topic for this thread) so that i might look into building my own.

salimshah

My work in this area has been limited to pre-amp out [as supplied by ipod-nano and to be comaptible with any eclronics audio product]. Tomv has successfully used the headphone out [not sure but with additional boost from belkin] .. see my diatribe of signal level in this thread...
He can give you the exact details as what volume level to set for optimal settings are. If you are getting something that does not match-up with Tomv, may be you have wiring issues.

Nakamichi system in Lexus are common and work on the same principal. [ I have verified it on SC, RX and LS models]. I did a bread-board and then have gone through building a prototype.

I am finding that MOST users want a plug and play solution .. they do not want to cut/splice wires. I dont have that solution as I do not have access to a source that sells plugs for Lexus/Nak.

Then there is a group of few (myself in that catagory). who are willing to cut/splice but are sensitive to pricing. This group also needs to know what they are doing or need to work with professional installers.

Unless, I get into volume production, the price is very dependant on silly (my view) things like box/packaging $12-$15. I would love to launch this off, but things are on hold till I get the plugs or have a better idea of the size of the second group to go into volume production. Cost per unit of the protype, currently requires me to subsidize it substantially or loan it out. The loaning part does not even pass my sanity check as it would required the testor to cut his/her harness and then return the product.

Bye the way the boxed unit is 5x1.75x3 with 12" leads. The ckt board is 4x1x2.5


Salim

mcowher

Any reason I can't daisy-chain two of these together and combine then with a 3-position rocker switch and provide 2 additional inputs, like an Ipod and a DVD player's audio?

salimshah

Should not be a problem. Expect signal level problem, as discussed before. Watch out for noise or bleed through. Bleed through can be controlled by turning off the sorce not being used,

Salim

miniround

I have one quick question,

Does anyone live near Boca Raton, FL and would like to put and AUX IN into my RX because i'm not all that technical with wires and such...

SO if you do live near me please email me at Boychik21@aol.com and put in the subject "I LIVE NEAR YOU"

thank you,
ajk

mcowher

Salim,

Would this product be a sufficient way to convert unbalanced audio to balanced audio?

ARTcessories CleanBOX

mcowher

Here's a link to a DIY Unbalanced-to-Balanced Line Converter:

DIY Unbalanced-to-Balanced Line Converter