Just opened boxes for two Alesis RA500 power amps sent me by Simon for very reasonable s/h price. Having had the gain controls removed (by Simon) the amps have 150 watts per channel or can be set to mono-block mode with 500 watts each. "They are basically as close to a blameless power amp as you will likely find."
My plan is to assess these as monoblocs, running in fully balanced mode from my Dax Decade and into epos es22 standmounts - or into some future speaker upgrade. If that doesn't work out then, the options are to give them as stereo gifts to offspring or sell them on.
I decided to sit and read the manuals while I listened to some music, especially the bit on setting them to mono mode. The manual has some nice features, readability being one. These include a final page entitled "Architect's and Engineer's Specifications". There are also the following passages about speaker cables and impedance, the first two amusing, the third, the subject of a question to them that knows:
1. "In recent year years, expensive audiophile cables of high current capacity have appeared. these have been somewhat controversial; some feel ... "
2. "Never use shelded guitar cords as speaker cables."
3. "... it is possible to use it as a mono amplifier with twice the power. This uses both sides of the amplifier in a push-pull configuration, so the speaker must be wired differently. .... However. note that the minimum load impedance is 8 ohms, instead of the the 4 ohms in stereo operation"
That last remark had me thinking.
The impedance for my speakers is 6 ohms; sensitivity 87 db. They have a 1 inch dome tweeter and twin 6 inch midwoofer and bass driver. This loudspeaker does not use a crossover, just a capacitor to protect the tweeter. The amplifier connects directly to the drivers.
Should I be concerned?
My plan is to assess these as monoblocs, running in fully balanced mode from my Dax Decade and into epos es22 standmounts - or into some future speaker upgrade. If that doesn't work out then, the options are to give them as stereo gifts to offspring or sell them on.
I decided to sit and read the manuals while I listened to some music, especially the bit on setting them to mono mode. The manual has some nice features, readability being one. These include a final page entitled "Architect's and Engineer's Specifications". There are also the following passages about speaker cables and impedance, the first two amusing, the third, the subject of a question to them that knows:
1. "In recent year years, expensive audiophile cables of high current capacity have appeared. these have been somewhat controversial; some feel ... "
2. "Never use shelded guitar cords as speaker cables."
3. "... it is possible to use it as a mono amplifier with twice the power. This uses both sides of the amplifier in a push-pull configuration, so the speaker must be wired differently. .... However. note that the minimum load impedance is 8 ohms, instead of the the 4 ohms in stereo operation"
That last remark had me thinking.
The impedance for my speakers is 6 ohms; sensitivity 87 db. They have a 1 inch dome tweeter and twin 6 inch midwoofer and bass driver. This loudspeaker does not use a crossover, just a capacitor to protect the tweeter. The amplifier connects directly to the drivers.
Should I be concerned?
