Full Range Home Audio Project

[ANeonRider 3]

I also play all of my music & movies through my computer, so a sound card is in the plan. Likely the AV-710 from Chaintech, since it is very budget friendly & everything I have read has said its performance on music & movies is excellent (I don't game).

[///M5 2,833]

I have a couple 710's, sent one to Adrian and having nothing bad to say other than they are more expensive now than when I bought mine.

[topgun 262]

I'm even looking into building another pair, not any bigger though.

Wuss. You know you want to do 15's.

That'd be something...B&C 15's in a BIB and Altec sectional horns for the midrange/top end...yikes.

Do NOT give me ideas.

[ANeonRider 3]

I'm listening to the amp right now, on a pair of cheap satellite speakers. Not sure why I had it collecting dust, sounds great.

Tomorrow one of the guys from work is bringing me an empty rack enclosure. I am going to transplant the amplifier guts into the rack, after I test it in the current enclosure tomorrow. I'll retest and see if it made any difference.

Why?

1. More space, so I can seperate the transformer from the rest of the components as much as possible.

2. Rack mounting is ideal for the entertainment center I am envisioning.

3. Better cooling, the guts are currently pretty stuffed into the present case.

I found my electronic format of the documentation. I'll be posting it asap.

[ANeonRider 3]

Documentation

Take the measurements listed with a grain of salt, the testing done was very much sub par.

I need to install PSpice to get some larger pictures of the schematics.

I still have .bmp's of all of the board layouts as well.

[ANeonRider 3]

Ordered the plate amp & a pair of the CSS FR125S drivers tonight.

[///M5 2,833]

dammit I wanna build something

[Adrian_D 520]

I'm listening to the amp right now, on a pair of cheap satellite speakers. Not sure why I had it collecting dust, sounds great.

Tomorrow one of the guys from work is bringing me an empty rack enclosure. I am going to transplant the amplifier guts into the rack, after I test it in the current enclosure tomorrow. I'll retest and see if it made any difference.

Why?

1. More space, so I can seperate the transformer from the rest of the components as much as possible.

2. Rack mounting is ideal for the entertainment center I am envisioning.

3. Better cooling, the guts are currently pretty stuffed into the present case.

I found my electronic format of the documentation. I'll be posting it asap.

nice and simple. i love it

[ANeonRider 3]

Just completed the full power testing, so I figured I would share.

Equipment

• Hewlett Packard 4935A Transmission Test Set
  
• Tektronix TDS 3032B Digital Oscilloscope
  
• Fluke 189 True RMS Multimeter
  

Testing Procedure

Test #1: This test will full power test each channel separately for comparison with the all channels test to follow.

• Connect a 4 ohm resistor load to the left channel output.
  
• Connect the transmission test set, which will be set with a 0dB 1kHz sine wave to the left channel.
  
• Measure RMS voltage across the load resistors at the point of clipping with both the oscilloscope & the RMS multimeter.
  
• Repeat for the right channel.
  
• Repeat with a 8 ohm load.
  

Test #2: This test will full power test both channels simultaneously, also known as the all channels test. This test challenges the transformer & power supply to provide the necessary energy to power both channels at full output power.

• Connect a 4 ohm resistor load to the left & right channel outputs.
  
• Connect the transmission test set, which will be set with a 0dB 1kHz sine wave to both channels.
  
• Measure RMS voltage across the load resistors at the point of clipping with both the oscilloscope & the RMS multimeter.
  
• Repeat with a 8 ohm load.
  

Testing Results

All verified with the Fluke RMS multimeter.

Test #1

Left Channel

17.6 Vrms into a 4 ohm load: 77.44 Wrms

19.2 Vrms into a 8 ohm load: 46.08 Wrms

Right Channel

17.6 Vrms into a 4 ohm load: 77.44 Wrms

19.2 Vrms into a 8 ohm load: 46.08 Wrms

Test #2

Left Channel

17 Vrms into a 4 ohm load: 72.25 Wrms

*** Vrms into a 8 ohm load: *** Wrms

Right Channel

17 Vrms into a 4 ohm load: 72.25 Wrms

*** Vrms into a 8 ohm load: *** Wrms

Conclusion

The amplifier much preferred powering the 8 ohm resistive load, as the numbers show. Typically, an amplifier will double the power output when the load is halved. In this case, it did not. This could be associated to the transformer or power supply being undersized or the input voltage not being constant as I do not have a variac to keep the circuit from loading down. I am confident that the power supply was not able to supply the amplifier with the required output to properly drive the 4 ohm load, as the all channels test shows, the power output does not dip very much at all when the transformer and power supply is powering both channels at full output power & I know the input voltage would not be loaded down enough to limit power output like that.

I was happy to see that the output of both channels match for all tests.

I was unable to test the 8 ohm all channels power test due to not having enough high power resistors to make two 8 ohm loads. I will pick up more & complete the test at a later date.

During the 4 ohm operation, all components stayed cool, but there was a slight ~1kHz oscillation that I could hear coming from the amplifier when the output got very close to clipping. This oscillation disappeared when the 8 ohm load was introduced.

I would conclude that, while this amplifier can power a 4 ohm impedance perfectly fine, you will not gain anything by using it to drive this lower load.

Please read this to find out why.

Therefore, using this amplifier with an 8 ohm load vs. 4 ohm load will result in not only better performance, but a lower current draw, less internal component noise, cooler operation & a longer life.

[ANeonRider 3]

Just picked up two 4x8 sheets of 19mm maple.

$120 later

[ANeonRider 3]

Pictures!!!

Still have to attach the one side, forgot my spray glue for attaching the polyfill inside the horn.

The baffle I made

Should have the fabrication complete on this one tomorrow, then have the finishing to do. Then get started on the other one.

[JimJ 11]

Aw, they look dainty

Are you going to leave the plywood edges exposed? I'm wondering how to finish them on mine...

[ANeonRider 3]

I'm going to sand them as smooth as possible, then finish them with a very light stain. Might use a much darker stain on the baffle & footing though for contrast.

6 feet of tower for a 4.5" driver

[Chevy350TPI 12]

Very nice!

[DevilDriver 28]

Looks really good. It sucks to see someone out-progress me in less than a week...by a lot.

[ANeonRider 3]

Done!

Shitty cell phone picture, since I forgot the camera.

Still have to do the long tedious task of finishing it. I used cat litter for ballast, left a cavity about 2.5" high on the bottom for it. Also used home audio grade bolts for my terminals LOL.

I'll get to tower #2 some this week hopefully, but should be done by the end of next weekend.

[JimJ 11]

Everybody's finishing theirs before I'm done with mine

Looks great. Let me know how you end up with the stuffing...if any.

[ANeonRider 3]

I pre-stuffed with this material:

Did the whole length of the baffle & driver side of the port. Also used polyfill on the top of the driver side of the port. I'll see if my foresight works.

[///M5 2,833]

Looks great so far, hopefully I'll get to start on some this winter

[Aaron Clinton 2,372]

Wow, looks great. Unreal amount of internal space for such a little driver.

[ANeonRider 3]

[dem beats 1,223]

those look beautiful.

I've never heard a full range single speaker set up I have liked, but this looks amazing for the cost if it comes close to some of the 2 ways out there... well worth it.

Lookin seksay

[DevilDriver 28]

That copper phase plug still wows me everytime. It's almost Excel-errific!

[///M5 2,833]

That copper phase plug still wows me everytime. It's almost Excel-errific!

You took the typing right out of my fingers.

[topgun 262]

I've never heard a full range single speaker set up I have liked

Have you ever heard a good full range setup?