RCA output voltage while streaming Bluetooth audio? DD-1 helps find a problem!

[Wicks]

So my DD-1 helped uncover an issue with my Kenwood DNX-6990HD head-unit.

I was installing my new DC5K and wanted to check the output of my Kenwood again to make sure I wasn't feeding the amp a dirty signal.

Well, I was getting very weird readings with the DD-1, no signal but distortion at all levels and other flaky readings.

This was using the RCA's directly into the DD-1.

So I ripped the Kenwood out of my dash and did some troubleshooting.

Turns out that the "pico fuse" on my RCA grounds/outside conductors is blown.

I have no connection between the RCA outside conductors and the HU chassis.

The DD-1 worked great using the supplied cable with the ground lead attached to the HU chassis.

Fearing that something else may be faulty, I started to measure the RCA output with various sources.

Using the SMD DD-1 Test Disc with a 0dB track, I was able to measure about 4.7Vrms from the RCA's which is what I'd expect.

Then I switched to my iPhone4 and connected it to the Kenwood through Bluetooth which I often use since my iPhone has a noisy signal from the 30-pin connector. With the volume on the iPhone max'd, I could only measure about 1.5Vrms from the RCA's.

(All settings flat and volume max'd at 35, no clipping)

So...has anybody measured their RCA output from their HU while using a Bluetooth device?

I'm curious if this is normal or whether my Kenwood is indeed messed up.

I have an email into Kenwood but wanted to ask around here as well.

[Noel989]

Were is your is bass level and the HU?

I also have a kenwood and when I did mine I tried it at +10 and it clipped right away so I just went back and left it at 0 even though I was good at +4

Also mine didn't distort like yours at 35 but it sounded like shit when I went pass 31-32 so I retuned it to 30 being my max volume

[Guest]

kenwoods have pico fuses? you learn something new every day

[Wicks]

Were is your is bass level and the HU?

I also have a kenwood and when I did mine I tried it at +10 and it clipped right away so I just went back and left it at 0 even though I was good at +4

Also mine didn't distort like yours at 35 but it sounded like shit when I went pass 31-32 so I retuned it to 30 being my max volume

Bass was flat. I can raise it to +2 before it distorts but I leave it flat.

Sub level also can go to +2 before it distorts.

With flat settings, the volume can go to the max of 35 with no clipping or distortion.

That's what I used to measure the RCA output.

[Wicks]

kenwoods have pico fuses? you learn something new every day

News to me too....

It must have one 'cuz the outside conductor of my RCA's has no ground connection at all. Resistance between the RCA outer conductor and the chassis is in the mega-ohm range.

Therefore I'm concluding that it has a "pico fuse" and its blown.

We'll see what Kenwood comes back with, but I can't possibly imagine this HU is set up to return the RCA signal through the chassis ground....