Newb amp help

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Is there someplace on the web that defines each part of these equations and what they correlate to?

ie what is P1 and P2? I did some searching and re-read through the thread but do not see where I get those 2 values from.

I need to draw it out on paper and that would help me a lot. Power in, what happens to it at each stage, output, etc...

I have zero electronics, electrical, etc background. The most math I have employed is a month or so ago at work we all sat down to figure out how wide a 42" 16:9 TV was :)

So I'm afraid I'm going to need a more simple explanation or at least something comparative I can use to draw a parallel to.

Eventually the light will click and it'll make sense.
 
Hi,
do you have a calculator?
Check to see if it has "log" and "10^x" .
P1=117W
P2=50W
P1/P2=117/50=2.34
Log 2.34=0.369
10*log2.34=3.69.
You can enter this log(117/50)=*10= to see the result. You may be able to omit the first "=" and still get the correct result.

The extra 67W adds 3.69db to your sound level.

92db speakers and 50W gives 109db.
92db speakers and 117W gives 112.7db.
My answer is that if the volume is set to just below clipping the Yam will sound slightly louder than the chipamp, but only if you can set the volume control accurately enoughto hear that 3.7db difference.
I suspect the two amp will be difficult to determine which is louder due to other differences between the amps, eg, response variations, peak transient power, bass strength on sustained notes etc.

BTW,
subtracting 20db from these near 110db levels to give the average level results in 90db, this is pretty loud.
we all sat down to figure out how wide a 42" 16:9 TV was
you are saying this was a team effort!
 
OK!

Thats where you were getting the 117 from, from me...I did not catch that part.

Now it makes sense.

As far as which is louder your right I won't be able to tell the difference. I've played around with my system when I first got it and found 103db to be its limit before it started to break up.

I just sat down while listening to Bob Marley on a very well produced CD and could hit 103db crystal clear...if you can define 103 as clear. Once I got over 103 it started to go into protected mode and shut off. This was at roughly 10' to the right of one of the speakers. At 1 meter it would have been spot on I believe. So I do not reach the limit with what I currently have and won't with the chipamp either.

The question more is which is going to sound "better". I can hear a difference between regular mode and PURE mode which turns off all the video processing.

I've heard dedicated amps sound better and I guess I'll have to wait until I get it together to see. All the parts should be here by Friday.

Thanks again, your last example made perfect sense and filled in a lot of the blanks for me.

This is what I ordered from PE, am I missing anything?

060-424 SPDT ROUND SNAP MOUNT ROCKER .. 1 0 $1.90 $1.90
070-070 12V RED INDICATOR LAMP .. 1 0 $1.25 $1.25
074-022 3A MINI CIRCUIT BREAKER .. 1 0 $1.95 $1.95
091-1120 DAYTON RCA-CHRB RCA CHASSIS M .. 1 0 $5.98 $5.98
091-1245 DAYTON BPA-38G HD BINDING POS .. 2 0 $6.88 $13.76
122-640 AVEL Y236750 330VA 25V+25V TO .. 1 0 $60.33 $60.33
090-442 IEC POWER JACK CHASSIS MOUNT .. 1 0 $1.78 $1.78
370-038 DAYTON SLDR-S4P-8 4% SILVER S .. 1 0 $18.00 $18.00

Those are, rocker switch, 12v LED, 3amp circuit breaker, Dayton RCA connectors(2), Dayton binding posts(4), Avel 330amp transformer, standard 3 prong power input and some 1mm solder.

Minus the case itself am I missing anything? I have some heatsinks at home for some old Pentium III's which should work.

I decided not to do volume control but will want to add it in the future. I looked at all kind of potentiometers but did not know which one to get. The examples I looked at all looked different that what was offered.
 
Based on what Andrew said, no it should sound the same at normal listening levels.

When I get everything I might test it at 1 meter with some sound protection. I could barely sit here turning it up to hit 103 on the meter for a few seconds. I could never get that close to the speaker without some good protection.
 
Another question...I was looking up my entire speaker set.

My fronts are 92db efficiency, my center is 91, and my rears are only 90db.

I have the same 135 watts going to each. Is this compensated for in the auto setup by boosting each speaker?

The room EQ option that just takes into account room effects or does it also figure in efficiency. It doesn't know the efficiency but the speaker would be quieter for a given voltage correct?

I'm talking about Yamaha's YPAO room auto setup.

Should I leave the auto values alone or should I go back and add in a set number of db for each speakers efficiency difference?
 
:headbash:

The best and most real sounding recordings I have heard were those that were made when they had 2 mikes and 2 tracks.

It seems the more capable technology allows us to accurately reproduce the original performance, the more we are determined to destroy it with dsp.

Sorry if this is OT.
 
David,

Outside the realm of DTS/DD I have had far better luck with just pure analog. All I do is run my CD/DVD player through a analog crossover/bass manager and in pure through my receiver.

This provides the best sound for DVD-A/SACD/2 Channel stereo. I have not made use of any of the receivers functions for a while now except as an amp and a video switcher.

That does however leave the speakers out of balance, I think, in the fact that the fronts are more efficient than the rears/center. If the recording, especially in 5 channel, are produced with the idea of equal output then it will not sound right since I am down a few db on the center/rear.

Now the problem is, on the analog side I have no way to compensate. At least not until I get a 5 channel amp :)

I have tried it everywhich way on the analog/digital side and nothing sounds as good as analog.

DTS/DD is a different story. The sound levels are equal and sometimes my DVD player does a better job and sometimes my receiver does a better job depending on the movie. When I do it with the DVD player its again out the analog 6 channel outs with it doing the DTS/DD decoding. When the receiver does it then its applying all the DSP adjustments.
 
davidlzimmer said:
...The best and most real sounding recordings I have heard were those that were made when they had 2 mikes and 2 tracks...

Heck...the best recording I heard was done with ONE mike :D

I think that this was out of print for a while but check out The Philadelphia Orchestra — Nature's Realm and other Water Lily stuff...awesome.

http://www.waterlilyacoustics.com/main.htm
 
All my stuff showed today!

Great and fast service from Chipamp. I ordered it at 11pm on Christmas eve and it showed today.

PE also delivered and now that I took a look at things I'm back off to RS to pick out a case, a smaller LED, larger standoffs, and a better soldering iron since I did not realize how small the boards were.

There is one big thing that is missing from the directions and that is what kind of wire to use to wire the whole thing together.

Going to pick up something at RS and see how it goes.

I also picked up all my stuff for my 24"x44" Sonotube today, going to be a busy weekend.
 
Help!

Ok I put it all together and now am getting to wiring the transformer.

Its the 25v+25v 330va Lindberg unit from PE.

It says to connect the primaries to the AC line. I have a 3 prong standard AC connector and the transformer but I do not know which are the primaries that goto the connector. The connector has 3 outputs, I assume positive, negative, and ground. I'll guess that ground is the 3rd pin in the middle.

The colors on the transformer are blue, grey, violet, brown, black, red, orange, and yellow.

I don't know how to read the schematic on the transformer but it LOOKS like it should be blue and violet. They each have a mark and in the middle it says 2x115v. Black and Orange say 0v, tellow and red are 25v/6.6a. Gray and Brown are blank.

Everything came out OK except I did lay all the parts out, bad idea I found out since the PS and amp parts look similar and I did solder one in the wrong place. I chipped it a little removing it but then did solder it in the other board. I'm not sure if I should replace it but I won't know if it will work obviously until I power it up.

Overall not too hard of a job and I'm anxious to power it up :)

Thanks for everyones help, my wife is amazed the swearing has been to a minimum :)
 
OK

I got the sheet from PE.

On the Primary side: Strap the blue and the violet together. Strap the grey and the brown together. This goes to the AC with a switch and fuse in series.


On the secondary: Black and red = 25V
Orange and yellow = 25V

These go to the power supply per the instructions.
 
After I twist them together and pass them onto the circuit breaker I can use a single wire correct to goto the power switch and then to the power plug, should I double the gauge so it is total gauge of the two pieces I am tying together?

If there are three prongs on the input adapter(standard US computer plug), does it matter which is which, or just pick two? What about the ground or third prong?

I assume they are beveled so one side is always positive and the other negative, but neither are labeled on the piece I bought that you plug the power cable into.
 
After I twist them together and pass them onto the circuit breaker I can use a single wire correct to goto the power switch and then to the power plug, should I double the gauge so it is total gauge of the two pieces I am tying together?

You do not need to double the gauge. In fact if the leads are long enough, after cutting, use the remaider for hook up.

If there are three prongs on the input adapter(standard US computer plug), does it matter which is which, or just pick two? What about the ground or third prong?

As you look at the "inside the chassis" view of the power plug, the post on the uper left is the "hot" conductor. this is the side the fuse and switch should be connected then the Blue and Violet of the transformer. The other (common)should go straight to the (grey and brown) of the transformer. The third connection (center bottom) is the ground. It should go to the chassis.

This ground is to protect YOU. If one of the "hot" wires were to be cut and connected to ground, the groung connection will cause the breaker to pop.
 
I assume they are beveled so one side is always positive and the other negative, but neither are labeled on the piece I bought that you plug the power cable into.

At this point there is no negative or positive. This is AC. You have a "hot" a return or common, and a ground for safety. Follow the previous post.

Note: Notice the * on the diagram on the transformer. Those are to help you keep the coils in "phase".

Actually this is more important than how you hook up to power.

One more thing. I've noticed a lot of guys swear on this practice and I will certainly do it from now on.

While in testing phase, wire up a light bulb (use an old lamp) in series with the transforme primary. If it glows bright, shut down immidiatly.

This could save you a lot of real sorrow.
 
davidlzimmer said:
One more thing. I've noticed a lot of guys swear on this practice and I will certainly do it from now on.

While in testing (and modification) phase, wire up a light bulb (use an old lamp) in series with the primary. If it glows bright, shut down immediately.

This could save you a lot of real sorrow.
absolutely definately.
Build a plug top, bulb holder and socket outlet and wire them up in a small insulated box. Keep it for every project that gets modified or built.
 
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