Help for TA850 users
I was having problems installing my new TA850, and I couldn't find the solutions on here, so I just experimented until I figured it out. I thought I'd post my results to help out other people with the same problems.
- 2003 Mazda Protege, 4 door sedan
- factory stereo (didn't want to upgrade)
- 6 factory speakers
- TA850 Bazooka tube to be mounted in the trunk
Problem #1 - needed to find inexpensive color coded 14 or 12 gauge wire for power and ground
Solution - Home Depot sells it cheap by the meter in all kinda of colours. They also sell speaker wire in various sizes. Total cost = $12
Problem #2 - user manual said to connect high level inputs to the speaker leads. It didn't say if this was to be done in parallel (across each wire pair), in series (in line with each wire pair), or instead of the factory speaker (ie. disconnect the speaker, connect instead to the tube). Maybe I just didn't see it?? In any case, might seem like an obvious thing to people familiar with SAS products, but not to others. Plus there were no detailed wiring diagrams to help out.
I have a background in electronics and I know that parallel connections reduce the total impedance 'seen' by the amp (or in this case the factory stereo). Unless the stereo is designed for that, it's can cause damage in some units, unless the Bazooka tube has some fancy circuitry. I took the risk anyways and experimented...
Solution - Wire the high level inputs in parallel (ie. green to positive speaker lead, green with black to negative speaker lead, etc.), while keeping in mind the next solution and the "Am I In Phase?" section of the manual.
Problem #3 - Everything was connected, but there was no bass. Tube was configured to use the Auto-On feature. Tested 12V, ground, and speaker wires -- all OK. No direct solution found on the forums.
Solution - To rule out a bad TA850 (or a bad Auto ON circuit), I disconnected the Auto-ON and temporarily connected the orange remote on wire to the 12V power lead (Quick tip -- the 12V lead was already crimped, so instead of removing it or running a new 12V switched wire, I just stuck the orange lead into the hole of the crimped wire to touch the 12V -- worked like a charm).
The amp now turned on but the bass was very low. Using the guide, I discovered one of the speaker leads was wired out of phase, despite the coding of the factory wiring. Swapped the green wire leads and I now had bass with the balance in center position.
So far so good. Disconnected orange remote lead from 12V power, and reconnected the Auto ON jumper. Tested again. Everything worked great this time.
What fixed it? Well, the TA850 was configured for Auto ON (watching for a high level signal from the speakers). I believe that since the polarity of one of the wire pairs was reversed, making the signal out of phase, the signal was too low to trigger the Auto ON circuit. That's why the orange lead remote on worked, but the AUto ON didn't... at least until I fixed the phase problem.
If this is true, then everyone should note... AUTO ON does NOT work if the speaker leads are out of phase.
Perhaps one of the SAS techs can confirm this....
Problem #4 - Optimal position for the tube is rear firing (ie. speaker facing the rear of the car, a few inches away). Didn't like the positioning of it (too up too much room), and had a problem with mounting (see my next problem)
Solution - Experimented and discovered firing into the back seats or into the open trunk greatly reduced the bass. The 2nd best position was side firing, firing into the wall of the trunk (with a few inches clearance). I moved it right up against the front wall of the trunk -- the section closest to you when you open it.
Problem #5 - Needed to mount the tube to the chassis, but didn't want to drill through carpeting into the sheet metal. Couldn't drill through the thin wooden cover o