Your opinions on assembled amplifiers!

rshri

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I have a pair of very old Panasonic speakers (250W) that were once part of an ancient audio system. That audio system has long gone kaput, but speakers look and work fine. I want to utilize the speakers by pairing them with a "value-for-money" amplifier.
I see listings of assembled stereo amplifiers on eBay, Flipkart and Snapdeal. Do they work as good as branded entry level amplifiers? Any recommendations?
EDIT:
Forgot to mention, my primary usage for this will be movie watching!
 
Put a pic of the speaker if possible, both the front and back side, off grill would also be nice. Is it 250W PMPO or 250W RMS?

I have a pair of very old Panasonic speakers (250W) that were once part of an ancient audio system. That audio system has long gone kaput, but speakers look and work fine. I want to utilize the speakers by pairing them with a "value-for-money" amplifier.
I see listings of assembled stereo amplifiers on eBay, Flipkart and Snapdeal. Do they work as good as branded entry level amplifiers? Any recommendations?
EDIT:
Forgot to mention, my primary usage for this will be movie watching!
 
Put a pic of the speaker if possible, both the front and back side, off grill would also be nice. Is it 250W PMPO or 250W RMS?

Thanks for your attention!
Here are the pics. I don't know about PMPO/RMS. Its sticker just says - "peak input" is 250W. Not sure what to make of it.
 

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For this speaker, A 35- 50W RMS @ 8ohms amp would do the job. If you can find a decently assembled MOSFET amp (HEXFET like IRFP150-240-250) or other amps like TIP3055, TIP142/147 or even 2N3055 would work.

TDA7294, LM3886 chip amp would work. STK4141-4191 amp would work. 2SC5200 or newer TTC5200 based amp is more than enough for your speakers.

There are Indian brands like DNM, JNM, Norge Audio etc who have decent vfm amps.

Norge 2060 - Norge Audio

Norge 4242 - Norge Audio

http://www.jnmaudio.com/av499.html

http://www.jnmaudio.com/a8080.html

I think you have to contact them for price.
 
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Thanks Sarith! Please bear with me if this is a stupid question -
Doesn't 250 W "peak input" mean that I should go for around 300 RMS amp (150W X 2)? I am surprised by recommendation for low RMS (30-50W) amp.
 
Thanks Sarith! Please bear with me if this is a stupid question -
Doesn't 250 W "peak input" mean that I should go for around 300 RMS amp (150W X 2)? I am surprised by recommendation for low RMS (30-50W) amp.

Peak power is simply a measurement of how much power can be generated or handled for very short bursts while RMS wattage rating is a measurement of continuous power (courtesy internet). I don't think there's an exact method or value to determine RMS from the given Peak power rating.

I normally divide the peak rating by 11 to estimate RMS. If a speaker has a rating of 1000W peak, divided by 11 gives 90W RMS. I would recommend a maximum of 125W RMS amp for a 90W RMS rated speaker (extra wattage as a reserve though not compulsory. A 90W RMS amp would work just fine). Though I use a value of 11 to determine RMS, I use the value of 8 to determine the RMS power output of an amp (hence 125W RMS).

From the pic of your speaker, In think the woofer is a +/- 6" one, mid/tweeter is like +/- 2" one and the tweeter seems like a Piezo-buzzer disc which doesn't play much of a role in sound reproduction.
35mm-Piezoelectric-Ceramic-Element-Buzzer-Disc.jpg
 
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Your speaker size guess is absolutely right! I just measured it. Its 5 inch woofer and 2 inch mid. Please see attached pic.

I also managed to lay hand on service manual of the original receiver that worked with these speakers. Please see attached pic.
Is it possible for you to infer RMS value from this data?
 

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The RMS value is the first number: 43W. Sarith was spot-on. And that is when it is blasted at top volume continuously. At normal to decently loud listening levels, your speaker would need about 20W of power.

You should just ignore the peak watts or PMPO number. That is just a marketing gimmick.

Your speaker size guess is absolutely right! I just measured it. Its 5 inch woofer and 2 inch mid. Please see attached pic.

I also managed to lay hand on service manual of the original receiver that worked with these speakers. Please see attached pic.
Is it possible for you to infer RMS value from this data?
 
The RMS value is the first number: 43W. Sarith was spot-on. And that is when it is blasted at top volume continuously. At normal to decently loud listening levels, your speaker would need about 20W of power.
First number is (43W X 2). So this should mean 86W RMS amplifier. Right?
 
Your speaker size guess is absolutely right! I just measured it. Its 5 inch woofer and 2 inch mid. Please see attached pic.

I also managed to lay hand on service manual of the original receiver that worked with these speakers. Please see attached pic.
Is it possible for you to infer RMS value from this data?

Continuous power output=43W. Like I said there is no actual method to determine RMS from PMPO. Here, if you divide 500 by 6 you get 83 which is close to continuous power output of 43x2=86W @ 6ohms.

If you divide 500 by 8 you get 62.5W which would almost be the rating of a 8ohm speaker. Don't bother with all these calculations.

A 5" woofer (BY Salora for Panasonic) would not benefit from anything more than 50W I guess. A 50x2=100W amp is enough.


A 1700W PMPO Aiwa system is rated at 200W RMS (1700/8=212.5). A 3700W PMPO Aiwa system is rated at 370W RMS (3700/10=370). A 3000W PMPO Aiwa is rated at 270W RMS (3000/11=273). Pic of 3000W Aiwa as an eg.

1548350-aiwa-jax-d5-hi-fi-system-1.jpg
 
Thanks for helping me understand & form a decision!

So it turns out that these speakers are not really worth bothering about. All these years I was under wrong impression that they were something special :)

I still have the original receiver lying around, I will try to get it repaired. If its not repairable, I will most likely buy Norge 2060 (So that I have a decent amp for use with speakers too, if need be).
 
Thanks for helping me understand & form a decision!

So it turns out that these speakers are not really worth bothering about. All these years I was under wrong impression that they were something special :)

I still have the original receiver lying around, I will try to get it repaired. If its not repairable, I will most likely buy Norge 2060 (So that I have a decent amp for use with speakers too, if need be).

Try the speakers out with a Norge amp. You might be surprised at how good it sounds, and if so, you can keep using it :) I too was using some speakers from an old music system. Or maybe it won't sound that good too. Then you can look for some decent speakers. We can give some suggestions too based on your music type, room size, and budget.

The important thing is that it should sound good and satisfactory to your ears. Don't dismiss the speakers before hearing them with a decent amp first.

An important note: When we talk about a 40 watt (RMS) amp, it will supply 40 watts simultaneously to both speakers (channels). So to drive your speakers, you only need a 40 watt or higher amp. You don't need an 80 watt amp.
 
The RMS value is the first number: 43W. Sarith was spot-on. And that is when it is blasted at top volume continuously. At normal to decently loud listening levels, your speaker would need about 20W of power.

You should just ignore the peak watts or PMPO number. That is just a marketing gimmick.

First number is (43W X 2). So this should mean 86W RMS amplifier. Right?

Some how both these posts were not visible to me when I was posting my comment.

As Arun mentioned, ignore peak power rating, in future too. It is a gimmick. Too powerful amp wouldn't be as much a problem as an amp that run out of juice when pushed.

I would suggest spending little extra on a good amp, so in future you can upgrade to better, more powerful speakers and keep using the existing amp.
 
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First number is (43W X 2). So this should mean 86W RMS amplifier. Right?

I'm not an expert but to my knowledge, go for a little more power amp than 86W RMS. It may clip if you use lower out amp than 86W at some volume level.
 
I'm not an expert but to my knowledge, go for a little more power amp than 86W RMS. It may clip if you use lower out amp than 86W at some volume level.
Yes, I will make sure that whatever amp I choose delivers at least 50W per channel
 
I tried to contact 'Norge Audio' over emails for possibly buying Norge 2060 but never got any reply. Finally I called up and was taken aback by rude responses!
Would you believe that after hearing my polite inquiry (in Hindi), the man said loudly - "NO! DO NOT WANT" and hung up the phone?
Stunned, I called up a second time and inquired again (this time In English). This time the man responded but response was very flat, blunt and authoritative.
I then decided not to engage with 'Norge Audio' in any way.

Since other branded amps are too expensive for my need, I am now buying an assembled amplifier for these old speakers. I have settled on a chip based amp built over STK4231. It has toroidal transformer and Bluetooth too. Getting it for around 5K.

Will let everyone know about how it fares after I receive it.
 
This is somewhat surprising going by the very positive image Norge audio has in the forum.

Norge 2060 will be a a few miles ahead of the amp that you are getting, if possible give them the benefit of the doubt and try once more, but then again only you experienced what or how they behaved so it is your call.
 
I tried to contact 'Norge Audio' over emails for possibly buying Norge 2060 but never got any reply. Finally I called up and was taken aback by rude responses!
Would you believe that after hearing my polite inquiry (in Hindi), the man said loudly - "NO! DO NOT WANT" and hung up the phone?
Stunned, I called up a second time and inquired again (this time In English). This time the man responded but response was very flat, blunt and authoritative.
I then decided not to engage with 'Norge Audio' in any way.

Since other branded amps are too expensive for my need, I am now buying an assembled amplifier for these old speakers. I have settled on a chip based amp built over STK4231. It has toroidal transformer and Bluetooth too. Getting it for around 5K.

Will let everyone know about how it fares after I receive it.
i too had the same experience from norge. i first called then the person told me to mail my requirements and i sent 2-3 mails but no reply at all.this happened 1.5 years back. just now i sent a new mail through their website
 
The assembled amp & old ordinary speaker combo that I am setting up should prove to be adequate and satisfactory for intended audience (that is my family :-) which is not really discerning in audio stuff). It will be just used for watching Hindi movies 3-4 times a month.

If I choose to upgrade in future, I will dump both the old speakers and assembled amp and go for some 50K setup with Marantz/Yamaha amp & matching speakers etc, as per forum's advice at that time.

So it seems Norge has permanently lost me as possible customer. Not that they care :-)
 
Finally got the assembled 5K amplifier. Tested it with my old speakers. Sounds great!
It has Bluetooth, slots for playing through USB / Memory cards & FM. Good VFM and more than adequate for my needs!
 

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