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Rockville RPA16 Review (Pro Amplifier)

Rate this amplifier:

  • 1. Poor (headless panther)

    Votes: 68 43.3%
  • 2. Not terrible (postman panther)

    Votes: 67 42.7%
  • 3. Fine (happy panther)

    Votes: 19 12.1%
  • 4. Great (golfing panther)

    Votes: 3 1.9%

  • Total voters
    157

Doodski

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Well... that escalated quickly.
Yes, it did. Frankly I saw little to nothing to give me a red alert. I asked a question and received a answer. The stressful and merciless training I received in the electronics study made me flexible and appreciative of any information I can get about stuff. I made a obvious mistake in electronics theory, I should have double checked my figures with multiple approaches to the problem before setting up parameters and that was cleared up pretty clearly. No big deal. If that was some sort of shocker for some peeps they should have been there when I studied electronics. The instructors where very bluntly clear in explanations and hammered me till I got the ideas clearly in my mind at the time no matter what my mood was at the time. A simple comment regarding my techniques and my approach is no big deal. As another observation I have is that some peeps here really hash out stuff with some pretty blunt and sometimes aggressive banter and I've grown to not be surprised or shocked by that stuff. So I'm not in any way manner shape or form stressed. :D
Larry B. Loser be
There's no need for slagging anybody. :facepalm:
 
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amirm

amirm

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You know perfectly well that he meant continuous power.

Now that I think of it.
Is it necessary to to talk down to a forum member with over 9000 posts as if he knows nothing of the subject.
Did you not see the smiley face? I made the correction knowing full well that member @Doodski knows his stuff and in just this case, he goofed a bit. So I said it in lighthearted way as indicated by the smiley.

But no, I didn't know what is meant by "RMS" power. I made the correction so it didn't look like I was trying to define something that doesn't exist. And answered the question regardless.
 
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amirm

amirm

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Interesting results from your calculations. Ohm's law is only applicable to a purely resistive circuit, or an AC circuit with a power factor of one (non reactive)
The results must by definition also work for resistive load.

Expanding, the first step in designing an amplifier is what @Doodski showed. You need to compute how high your voltage rails need to be for 8 ohm load, and the current for lower impedances below that. These two then mandate the requirements for many things from power supply to capacitor ratings and output stage capability.

For higher peak, you allow the voltage but give up on providing the current longer than X amount of time. This is done with power supply capacitors being able to fulfill short term current/power needs.
 
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amirm

amirm

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One related note and warning: at these power levels, your speaker connections are now providing high voltage with ton of current! You better not touch your speaker terminals and use cabling rated for such high voltages. 95 volts with a ton of current is a killer!
 

DanielT

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But wait now. I'm not an EE but some of you who write in this thread are right? EE or engineers. Ohm's law was read about in primary school, if I remember correctly. So everyone read that in the physics lesson.Though it may be as Doodski said: Ohm's Law can get pretty complicated pretty fast though

How come you disagree with it, Ohm's law, now?
 

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Doodski

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But wait now. I'm not an EE but some of you who write in this thread are right? EE or engineers. Ohm's law was read about in primary school, if I remember correctly. So everyone read that in the physics lesson.Though it may be as Doodski said:

How come you disagree with it, Ohm's law, now?
Can you rephrase your question? I'm not sure what you are asking.
 

DanielT

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Can you rephrase your question? I'm not sure what you are asking.
I'm just trying to figure this out with RMS, temporary peak of power (dynamic power, if that's what it's talking about?) And Ohm (mentioned in the thread). I can not concretize it more than that. Sorry.

But do you not really agree? Why did Larry B get so angry?
 

GRBH

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But wait now. I'm not an EE but some of you who write in this thread are right? EE or engineers. Ohm's law was read about in primary school, if I remember correctly. So everyone read that in the physics lesson.Though it may be as Doodski said: Ohm's Law can get pretty complicated pretty fast though

How come you disagree with it, Ohm's law, now?
Actually I tried to to delete my reply, but I guess I was too late. I think I now recall, maybe wrong though, Amir does his testing into a resistive load, not inductive, therefore ohms law is applicable, if somewhat reactive not so.
 

Doodski

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I'm just trying to figure this out with RMS, temporary peak of power (dynamic power, if that's what it's talking about?) And Ohm (mentioned in the thread). I can not concretize it more than that. Sorry.

But do you not really agree? Why did Larry B get so angry?
RMS is not used here @ ASR when testing amp power output and I assumed that RMS power was quoted. My mistake. I should have approached the problem with varied approaches to prove and disprove the numbers before posting them. That one's on me. Sorry if I confused you.

I never saw Ohms Law in primary school...lol. If I did I don't remember. :D

I am not sure why Larry B was so frustrated/angry. I don't assume to know other peep's thoughts and emotions.
 

DanielT

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I never saw Ohms Law in primary school...lol. If I did I don't remember. :D
Some confusion.Translated text:
"Compulsory school in Sweden consists of the compulsory 9-year school (grades 1–9)"

It is year 9, in the physics lesson that Ohm's law is included in the syllabus. Then, if I remember correctly, Ohm's law applied to fairly simple examples.

... :)
 

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Doodski

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Expect some confusion.
"Compulsory school in Sweden consists of the compulsory 9-year school (grades 1–9)"

It is year 9, in the physics lesson that Ohm's team is included in the syllabus. Year 9 is compulsory for everyone.

... :)
I see. Primary school in Canada is grades 1 through 7. Then junior high is grades 8 and 9 and then high school is grades 10, 11 and 12 and even a extra year for grade 13 in one province of Canada.
 

DanielT

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I see. Primary school in Canada is grades 1 through 7. Then junior high is grades 8 and 9 and then high school is grades 10, 11 and 12 and even a extra year for grade 13 in one province of Canada.
OT:
Now I became curious, but when do students learn Ohm's law in Canada?
I mean Ohm's law at a basic level.:)
 

Doodski

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OT:
Now I became curious, but when do students learn Ohm's law in Canada?
Ohm's law at a basic level.:)
Grades 9 if one is taking a optional electronics study in grade 9. They skim Ohm's Law lightly and don't get too demanding on the study. I don't remember if it was taught in the general science class in grade 9. That was along time ago. :D
 

DanielT

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Grades 9 if one is taking a optional electronics study in grade 9. They skim Ohm's Law lightly and don't get too demanding on the study. I don't remember if it was taught in the general science class in grade 9. That was along time ago. :D
Aha. :)

 

Jake Cushing

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There's no need for slagging anybody. :facepalm:
Including me? :)

Look, Larry's post was outrageously aggressive and horrible to read. He could have made his point a jillion better ways.

Anyhow, I'm recent to the forum so whatevs :shrug:

Back to this amp!
 
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Snafu

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Fan in any home hifi device is no no for me.

I wonder how much it after all helps if your case has well planned ventilation ?
 

MakeMineVinyl

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Fan in any home hifi device is no no for me.

I wonder how much it after all helps if your case has well planned ventilation ?
I believe the fan is thermally controlled and is not spinning very fast when the amp is cold. It did spool up quickly as things heated up however.

A general trend is to rely more on fans and relatively less on heatsink mass in some amplifiers. In these amplifiers variable speed control vs temperature is very important to keep fan noise below audibility. In some very high power amplifiers both fans and large heatsinks are necessary to keep things cool enough. The general cut-out temperature where amplifier shut-down takes place is 85c.
 
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