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keep_hope_alive last won the day on August 10

keep_hope_alive had the most liked content!

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About keep_hope_alive

  • Rank
    Acoustics Engineer
  • Birthday 08/21/1978


  • About me
    love audio in all forms, circuit designing, electronics in general.
  • Name
  • Location
    Quad Cities, IL
  • Occupation
    Acoustics Engineer / Electrical Engineer - consultant specification design engineer - i control noise and room acoustics and design electrical power systems.
  • Interests
    move electrons
  • Audio System Setup
    Alpine DVA-9861, Alpine PXA-H800, Audison LRx5.1k, Hertz MLK-165, Hertz ML3000

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  1. keep_hope_alive

    Need help with Sony headunit watts?.

    Quoted for notification purposes. Hopefully the info above helps. Feel free to ask additional questions.
  2. keep_hope_alive

    Need help with Sony headunit watts?.

    Here is some information about how head units are built, what those amplifiers look like, and how they are configured. Head units use a small amplifier IC (integrated circuit) to power speakers. This chip is about the size of a quarter, in total. Consider the size of an entire aftermarket amplifier and you get an idea of what expectations you should have for this tiny circuit. For example, the picture below is of a pretty standard amplifier IC in a Pioneer-made head unit. It would have ratings similar to that of your Sony. In this picture, you see the IC removed because I was making some modifications, which aren't important to this discussion. That IC does ALL of the speaker amplification for all four channels. Next, consider the topology of the amplifier IC. It already has bridged/balanced outputs, meaning there is signal on both the + and - wire. You can think of the amplifier IC like an 8 channel amp that has already been bridged down to 4 channels. For this reason, it is not possible to bridge a head unit any further. Lastly, the typical rating method of IC amplifiers (used in home or car audio) is if one channel can produce rated power for one second, they can label the IC as having the capability of producing that power into any of the four channels - even if that isn't simultaneous. Meaning your head unit can, in theory and in the right conditions, product a signal equivalent to 52W into one 4 ohm load for one second. That may not be pleasant to listen to (given distortion) but it can make it happen. Part of the problem with simultaneous power output (such as all four channels simultaneously) is power supply requirements. Consider the current required to produce the rated 216 total watts the amplifier IC is rated for, then consider the size of the traces in the amp. You'd quickly realize the traces would melt and/or catch on fire if asked to supply that much current. As such, the actual total power output of all channels simultaneously is about the amount of one channel. in your case, that is 52W divided by 4 which is about 13W per channel. Even then, distortion is high, so the typical usable (i.e. pleasant to listen to) is about 5W per channel. So why can a head unit seemingly get "loud" on speakers? Part of that relates to the sensitivity of smaller, cheaper speakers. Those lightweight cones move more easily and with sensitivities near 90dB at 1W @ 1M means that at the listening position you could achieve around 100dBA per speaker. That will seem pretty loud in a vehicle with the windows up, even if it doesn't sound very good because the amplifier distortion is high and the speakers are inexpensive or not ideally mounted.
  3. keep_hope_alive

    Best bang/buck for XM

    I have the amplifier pin-out diagrams for 2014-2018 Accords. You don't really need to put an RCA on it since it is balanced. An amp/dsp with speaker level inputs is also a balanced input - and if there is a low level sensitivity setting you get easy termination, balanced input noise rejection, and a flat response.
  4. keep_hope_alive

    Edge EDB12A subwoofer not powering on

    you connect the REM (remote) wire to the blue ANT output wire at the head unit. Normally, there is an additional blue/white REM wire at the head unit. In some cars the blue ANT wire is only active when on the Radio input (think powered antenna).
  5. Good deal. Next time you can use a DMM to check for voltage on the wires you're using. That was going to be my next suggestion. Did you notice if the wires were just in the wrong position?
  6. keep_hope_alive

    is dsp necessary

    you get more control with a DSP. you get better crossover adjustment, more EQ channels, and more precise time alignment. If you want to have more adjustment, then yes, it is worth it. if you just want the crossover flexibility, the Pioneer in network mode should do the trick. What are you using for settings now?
  7. keep_hope_alive

    deck or amp hpf

    The nice part about the head unit is the ability to adjust it while listening and also get a precise setting. I would start at the HU and adjust and listen to the change. Then you can move to the amp if you want more adjustment (meaning other frequencies), with the understanding the accuracy of the amp pot is poor but you can listen from there.
  8. keep_hope_alive

    Best bang/buck for XM

    I have a 2014 Sport. The models with the lower touchscreen are made by Alpine and have a clean, flat 3V RMS Balanced output. You just snag the signal before the factory amp.
  9. keep_hope_alive

    A girl needs help install options

    Maybe this diagram will help for wiring the four 6x9 two a 2 channel amp. We would call this wiring left speakers in parallel and then wiring right speakers in parallel.
  10. keep_hope_alive

    Dual Battery Problem

    The battery isolator just disconnects the rear batter from the front when the car is off. The idea here is that extended listening with the vehicle off would only drain the rear battery. If you can send me the charging system schematics that illustrate how the PCM monitors and controls the alt, I can review for a possible bypass.
  11. You explained that both the ignition and constant battery are orange, please verify as this seems to be a typo. This is what I find for '78+: Constant 12V+: Orange Ignition Switched 12V+: Yellow Ground: Black Illumination: Gray Dimmer: Brown Antenna Trigger: Pink Some of the older cars used a common ground configuration which modern radios will not accept. Please verify if you speaker wiring is common ground or dedicated ground. Also, there may be a thick gray wire which is speaker and a thin gray wire which is illumination - be sure to not mix those up!
  12. keep_hope_alive

    Dual Battery Problem

    What vehicle are you using? I've been dealing with the Honda ELD for over 10 years. It will turn off the alternator to save fuel. I've developed a bypass for the ELD which is online and I can share if it is applicable to your situation. My ELD bypass operates on a simple premise: it tricks the computer to think the battery needs charging all the time (or when the user desires). This bypass is reversible, non-destructive, and doesn't throw error codes. It is unique to each vehicle and requires studying the vehicle schematics.
  13. keep_hope_alive

    A girl needs help install options

    you're getting it! well done. For the Dual brand 4 channel amp, you will wire it in bridged configuration for each coil. The attached thumbnail is from the Dual XPR540 manual. Channels 1 and 2 will be bridged to the subwoofer coil #1. Channels 3 and 4 will be bridged to the subwoofer coil #2. You want to get the gains set exactly the same - which is best done with a DMM. To do this, you play a test tone (50Hz is ideal). Then you measure the VAC (volts-AC) for each bridged configuration, getting them accurate to within 0.1VAC. When wiring the four 6x9 on the Encore, you don't have to wire it like the diagram exactly. Yes, all positives will combine but they can combine at the amp terminals. So route wiring from each 6x9 to the respective amp. On the Encore, you'll land two wires in each terminal. For all other connections, you'll only have one wire per speaker terminal. All speakers will only have one wire per terminal.
  14. keep_hope_alive

    A girl needs help install options

    Thanks for the quick response. You don't lose power output by daisy-chaining the RCA signals. That is what you'll want to do for multiple amps. The issue with using a 2 channel amp on a dual 4 ohm sub is you cannot wire the amp optimally. A dual 4 ohm sub wired in parallel results in a 2 ohm mono load, and the amp can't handle that. The alternate is to wire the sub coils in series for an 8 ohm load, but at that load the amp would provide half of the power it's rated for bridged (same as a coil on each channel), and when combined with the impedance spike at fs (free-air resonance) you'll have much less power than you want for the sub. This is why I didn't recommend using the Encore amp for the sub. I understand your planned placement now, thanks for clarifying. You can use the Kenwood for the front speakers then the Encore for the rear channels, then the Dual for the subs. The Kenwood and Encore can share the same signal and pass-through RCA is better than an RCA splitter (due to the voltage-gain relationship with head unit output impedance and amplifier input impedance). Even with a reduction of incoming voltage, the gain is actually input sensitivity which adjusts for the incoming voltage level. For example, if the head unit output is 2V than a 2V input sensitivity setting is appropriate to allow full volume use of the head unit. I am aware you have a 4 channel amp made by Dual. I understand how it can be confusing when talking about a Dual brand 4 channel amp wired in bridged configuration to a Clarion dual 4 ohm sub (two 4 ohm coils). The Clarion is dual voice coil with 4 ohms per coil, also referred to as dual 4 ohm. https://www.abtec.co.nz/Clarion_SRW1283_Discontinued_2007_2008_Model That means there are four connections on the sub, positive and negative for one coil, positive and negative for the second coil. Both of these coils need to be connected. With dual 4 ohm coils, you have two wiring options to connect them to a single channel: https://rockfordfosgate.com/support/wiring-wizard/ You can also choose to wire the sub to the Encore with one coil on channel 1 and the second coil on channel 2. When deciding which amp to use for the sub, you compare impedance options for wiring in parallel, series, or separate. When you look at the Encore amp ratings, notice there are three values; stereo at 4 ohms, stereo at 2 ohms, or bridged at 4 ohms. Also note that the total power rating is the same for 2 ohm stereo and 4 ohm bridged, and these are both twice of the total rating at 4 ohm stereo. This is typical as it follows Ohm's Law and the most common amplifier topology. So you can choose to use the Encore amp for the sub, and you'll only be able to wire it for half of the amplifiers capability, around 150W. You can choose to implement the 2 Farad cap. It is the least important part of the power wiring requirements when compared to how you wire and terminate power and ground cables. It doesn't matter where you put the cap since everything is already connected. One common method is to tie the cap into the distribution block. Another popular method is to put the cap right at the sub amp, but the difference between the two methods is trivial. Also note that the 2 Farad cap has much less energy storage than an AAA battery so choosing to implement it is your choice because you want to, not because it makes a huge difference. Of course, a "stiffening cap" does not replace the need for a good battery system and a good alternator.
  15. I'm trying to follow your logic here. A diagram would be faster to interpret your meaning. Are you changing speakers or just adding amps? It changes the answer. First step is to find a wiring diagram for your vehicle and the pin-out diagram for the amp harnesses. You may need to pay a one-time fee for a day access to a service technician website to get this info. You also need to determine what the signal is into the amp and what the amp does to that signal (it may add EQ, it may add crossovers, it may add delays, it may add chimes, it may add microphone noise cancelling, etc.). You need to know if the tweeters are amplified separate from the woofers. It is common for factory systems to have a small capacitor on the factory tweeters, which changes the wiring requirements. You can verify this by looking at the tweeters and reporting back. You can remove each of the speakers to look at the wiring colors then look at the factory amp and match colors with pin locations. You can also look at the head unit wiring and match that to the amp input harness. You can use a DMM to measure the output voltage from the head unit and look to see if you can just bypass the line output converters and use a cleaner signal before the amp. You can see a process I did for determining how to interface with a 2017 Malibu here: https://www.chevymalibuforum.com/forums/137-modifications-generation-9/92681-2017-lt-factory-radio-frequency-response-4.html#post783545