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Hello,

I have been using standard and sometimes better then standard amplified PC speakers.

I would like to purchase maybe a 7 to 8 inch speaker or speakers and build an amp to drive them.

I believe the output in wattage is about 2 watts, but what speaker impedance should be used?

I have had this Anan 100 since the the second run of transceivers, so I have had it since the beginning of time!

Thank you.
Ken

You do not want to use the powered speaker jack output to drive an audio amplifier.

The built-in audio amplifier is a TPA0202 in bridge-tied mode. You can check the data sheet, but it expects an 8 ohm speaker IIRC.

See this post: viewtopic.php?f=12&t=3350#p10780

Hello Scott,

Thanks for the reply as usual. I looked at the schematics and looked at the data sheets on this chip.

I copied a section of one of the data sheets that I have in question. The last statement that I have turned "Red" for a visual affect is what is in question. What Speaker output of the Anan should be used to drive a desire line level input. (Home Stereo)

From what I gather from the data sheet it doesn't make a difference, perhaps I over looked the info that is given. The data sheet below was taken from Page 34 within the data sheets themselves. From what I am also gather from the link you have supplied, it seem as I should use the "HeadPhone" jack to drive the line input of a home stereo. The whole time I have been using using the Anan-100, that is exactly what I have been doing anyway.

DATA SHEET INFO:
The main disadvantage, from a performance standpoint, is the load impedances are typically small, which drivesthe low-frequency corner higher
degrading the bass response. Large values of CC are required to pass lowfrequencies into the load. Consider the example where a CC of 330 μF is chosen and loads vary from 3 Ω, 4 Ω, 8 Ω, 32 Ω, 10 kΩ, to 47 kΩ. Table 2 summarizes the frequency response characteristics of eachconfiguration.Table 2. Common Load Impedances Vs Low Frequency Output Characteristics in SE Mode

RL ------------------CC---------------------LOWEST FREQUENCY

3Ω----------------330μF---------------------161-----Hz
4Ω----------------330μF---------------------120-----Hz
8Ω----------------330μF-----------------------60-----Hz
32Ω--------------330μF-----------------------15------Hz
10,000Ω--------330μF---------------------0.05-----Hz
47,000Ω--------330μF---------------------0.01-----Hz

As Table 2 indicates, most of the bass response is attenuated into a 4-Ω load, an 8-Ω load is adequate,headphone response is good, and drive into line level inputs (a home stereo for example) is exceptional.

Hello Ken,

I don't know if this is any value at all to you. My son had purchased a matching transformer for his car stereo. You connect it to the Left and Right
8 ohm outputs and The other side of the transformer is connected to the low level input of an audio amp. At one point there were may brands of them because it was a regular for people to connect low power output car stereos to high output audio amps. I had used one of his to connect high level speaker outputs of a home amp to drive another amp. I was doing this to get better control of my surround outputs from my Surround Sound receiver. Later, when surround receivers improved, I don't have to use this configuration. If I find it again I am going to put it on the back of my 7000 DLE and see what it sounds like. Maybe this is something you could do.

Allow me repeat myself: you do not want to use the powered speaker jack output to drive an audio amplifier. The impedance match is poor, an external attenuator is required to drop voltages to safe levels, noise performance suffers.

The headphone output is a better choice due to the lower signal levels, but still not an optimum one (impedance matching is still poor, levels relatively high).

Since you have an ANAN-100 you have access to the correct signals to be used for this application, which are the audio line out signals. I believe that they are pins 6 and 7 on the accessory connector (J16). You will have to verify this by looking at the Hermes schematic.

Use the right tool for the job: the audio left and right line output signals.

For more information on the source of those line output signals, which are also used to feed the TPA0202 amplifier IC, see this post: viewtopic.php?f=12&t=2612&p=4075

For any 7000 and 8000 users reading this topic, note that you no longer have easy access to the audio line output signals. For some unfathomable reason Apache did not see fit to bring them to the back panel. They are still available internally.

Thank You Scott,

I do not want to send anyone down a path best not traveled. It has been a long time since I wired my 7000 up. After your last post I thought ," I surely had audio outputs on the rear of the deck since I have nothing connected to the front jack?" I got my manual out and looked. I verified what you said (not that I didn't believe you). Sure enough no outputs. I then remembered I'm getting my audio from the audio stream through the ethernet utilizing Virtual Audio Cables. Gettin' old really stinks. That causes me to think I may need to audit my setup from time to time. Some things I should just remember.

Thanks for you patience and work in keeping us going in the "correct" direction.