Old speakers' power rating

[arkanoid]

Hi there,

I'm hoping that someone would help me decode the specs of my speakers.

For a very long time, I have had an old Panasonic SC-AK5 system.
The CD / Tape / Radio / Amp unit was repaired once around 10 years ago but it looks like the issue is back.

I'm thinking about keeping the speakers and buying a new amp.
However, I have an issue with determining how much actual rated power the speakers have.

The manual (and speaker stickers) says:

• 100W (MUSIC)
• 50W (DIN)
• 6 Ohm (impedance)
• 85dB / W (sound pressure level)

The amplifier specs are:

• 2 x 30W - 1 kHz continuous power output both channels driven
• 2 x 40W RMS

So what is the RMS for these speakers?
Is the MUSIC here the speakers' RMS?
Or is it peak power and the DIN rating value should be treated here as RMS?

The amp wattage is also confusing since it looks like it's underpowered against the speakers.

Thanks!

 

[Gray]

Or is it peak power and the DIN rating value should be treated as RMS?

Yes, that's more like it.

But, if you're thinking of buying a new amp, I would seriously consider buying some different speakers as well.
(And I say that as someone that loves Panasonic as a brand).

Say how much you'd like to spend on both....or indeed whether you really wish to stick with your speakers.

Out of interest, what's the fault with the system (and what was the repair last time?)

 

[landco]

Don't fill your head with unnecessary thoughts. You have small speakers, which are not a problem for any amplifier, and the problem of "compatibility" of speakers and amplifier in home audio also does not exist. Therefore, buy any home audio amplifier and listen to music.

 

[Integralista]

Hi, what kind if problem has your Panasonic system?
I have old experience with one Panasonic and one Technics mini systems. Their speakers were in sound quality far behind what was possible when systems were connected even with old Tesla 3 way speakers. JVC, Denon were producing well balanced systems with good speakers. Data regarding power output from amp or max power input on speakers is just infirmative. It does not say anything about sound quality. The best is to try some combination by yourself. BR.

 

[arkanoid]

But, if you're thinking of buying a new amp, I would seriously consider buying some different speakers as well.

I don't really want to invest in that right now. Maybe I'll upgrade the speakers in the future. I know that ideally, it would be best to sonically pair the amp and speakers from the get-go, but I don't wanna dive into that rabbit hole for now.

Out of interest, what's the fault with the system (and what was the repair last time?)

F61 error then and now. I don't really remember but something was resoldered. It's not worth paying for that again.

Don't fill your head with unnecessary thoughts. You have small speakers, which are not a problem for any amplifier, and the problem of "compatibility" of speakers and amplifier in home audio also does not exist. Therefore, buy any home audio amplifier and listen to music.

How about you won't be condescending and rude?
The speakers are small but there are amps with small power. An underpowered amplifier can be a problem.

 

[arkanoid]

Data regarding power output from amp or max power input on speakers is just infirmative. It does not say anything about sound quality. The best is to try some combination by yourself. BR.

I'm not concerned about sound quality but about underpowered amp and clipping.

 

[Integralista]

I'm not concerned about sound quality but about underpowered amp and clipping.

This is fairy tail. It is not about power only but efficiency (sensitivity). Good small amp need good speakers with higher sensitivity, lets say min 90dB for some small to mid room. Even 10 watt tube amp may produce room shaking sound but with speakers with snesitivity 96dB and more. For trial with your Panasonic, you may try some old Mission Coda or Wharfedal or Bowers@Wilkins DM 302 speakers or similar (bookshelfs, not floorstanders). It may sound quite good. These speakers are on the market for a few pounds.

 

[twinkletoes]

Hi there,

I'm hoping that someone would help me decode the specs of my speakers.

For a very long time, I have had an old Panasonic SA-AK5 system.
The CD / Tape / Radio / Amp unit was repaired once around 10 years ago but it looks like the issue is back.

I'm thinking about keeping the speakers and buying a new amp.
However, I have an issue with determining how much actual rated power the speakers have.

The manual (and speaker stickers) says:

• 100W (MUSIC)
• 50W (DIN)

The amplifier specs are:

• 2 x 30W - 1 kHz continuous power output both channels driven
• 2 x 40W RMS

So what is the RMS for the speakers?
Is the MUSIC here the speakers' RMS?
Or is it peak power and the DIN rating value should be treated as RMS?

The amp wattage is also confusing since it looks like it's underpowered against the speakers.

Thanks!

HI there,

Well your going to have few problems unless you have few component lying around already to replace what the Panasonic SA-AK5 has on board. No?

The Pioneer A-307R (second hand) will run your current speakers fine but as mentioned wont have the functionality of your Panasonic. Or did you fancy something more modern?

Hope that helps a little

 

[arkanoid]

This is fairy tail. It is not about power only but efficiency (sensitivity). Good small amp need good speakers with higher sensitivity, lets say min 90dB for some small to mid room. Even 10 watt tube amp may produce room shaking sound but with speakers with snesitivity 96dB and more. For trial with your Panasonic, you may try some old Mission Coda or Wharfedal or Bowers@Wilkins DM 302 speakers or similar (bookshelfs, not floorstanders). It may sound quite good. These speakers are on the market for a few pounds.

Might happen almost never with modern speakers, but that's not my case.

My speakers are only 85dB, so that's why I'm trying to determine their RMS.

 

[arkanoid]

HI there,

Well your going to have few problems unless you have few component lying around already to replace what the Panasonic SA-AK5 has on board. No?

The Pioneer A-307R (second hand) will run your current speakers fine but as mentioned wont have the functionality of your Panasonic. Or did you fancy something more modern?

Hope that helps a little

I don't really care about the CD, tape or radio. A decent amp is what I'll be after.

As for this Pioneer - I'm looking rather for something new to avoid possible repairs, but thanks.

 

[nopiano]

My best guess for an approximate RMS power handling, based on the ratings in the spec, would be 30-35 watts. Hence the original amplifier was about right. However, the maximum handling of a speaker isn’t a target to hit, any more than your family hatchback top speed of 115mph is a recommended cruising speed.

I take your point that an 85dB sensitivity, if accurate (which I doubt) is on the lower side, but the weight tells you how modest they are. There are plenty of amps in the 25 to 50 watt range that will work ok until you can afford to upgrade, and still deliver satisfactorily into better speakers.

 

[GSV Ethics Gradient]

My speakers are only 85dB, so that's why I'm trying to determine their RMS.

RMS stands for Root Mean Square, and it's a way of trying to measure power meaningfully - as the electricity it emits is alternating with frequency RMS gives a positive in both directions. PMO/music power is something used to dupe, as it's a theoretical maximum at a very high peak - and is not sustainable or representative. Speakers don't therefore have an RMS rating.

Given the figures you have, you're looking for some compatibility between DIN on the speakers and the amp's RMS. They aren't a million miles out.

Ignore being told there is never a compatibility issue, although whether it applies really depends upon how hard you intend to use the system. An amp with too little power can struggle to control the drivers in a speaker, hence the rather counterintuitive notion that you are actually better with an amp with too much power - you'd know you were doing harm that way around because the sound would distort.

High volumes with an amp with too little power probably won't distort in the same way - you'll know when it's gone wrong when there ceases to be any sound from the tweeters. Voice of experience here. But if you are looking at low-to-medium volumes, it's unlikely that you would have any issues at all.

 

[twinkletoes]

I don't really care about the CD, tape or radio. A decent amp is what I'll be after.

As for this Pioneer - I'm looking rather for something new to avoid possible repairs, but thanks.

No problem. Ah well take your pick

rotel
nad
yamaha
marantz

All have affordable options and more expensive options if you feel you want to go down that route. None of them will have a bother running your speakers, and I wouldn't worry about numbers largely mean nothing . My friend ran is aiwa speakers into an separates amp for many a year before buying some mission 701's (that was a long time ago now)

 

[Links]

A good way to damage speakers is to power them with an under powered amp. The amp comes under strain , often with bass and the signal delivered is 'clipped'. This askes the speaker to move in a way which it is not designed for and causes irreparable damage. A better approach is to use a powerful amp, which will not be subject to this behaviour. as long as the volume is kept to a reasonable level, the amp will more than capable to delivering the required power and there will be no clipping. The power of the amp in true RMS into 8 ohms rating can be in excess of the speaker's recommended rating as long as you don't drive them to high levels and more than comfortable listening levels can be achieved.

 

[landco]

The speakers are small but there are amps with small power. An underpowered amplifier can be a problem.

There are no amplifiers on the market that will have problems with your speakers. Even with a minimum power of 20W

 

[arkanoid]

My best guess for an approximate RMS power handling, based on the ratings in the spec, would be 30-35 watts.

Given the figures you have, you're looking for some compatibility between DIN on the speakers and the amp's RMS. They aren't a million miles out.

I've found some details about a very similar system / model from Panasonic and it seems like depending on the region / logistics (or a year probably) it was released with lower wattage in the amp (30W RMS) and weaker speakers but also with higher amp wattage (50W RMS) and identical 50/100W speakers or weaker amp and identical speakers.

So it looks like my speakers are 50W RMS after all.

No need to explain RMS, PMPO, pushing the speakers to / over the limits, and amp stronger than the speakers approach.
In this case, it looks like the label MUSIC (100W) on the speaker is probably PMPO (Peak MUSIC Performance Output).

Given the low sensitivity (85dB) 50W for a new amp seems like a safe minimum.

 

[GSV Ethics Gradient]

No need to explain RMS, PMPO, pushing the speakers to / over the limits, and amp stronger than the speakers approach.

OK - although the first post reads as though that's actually what you were asking.

 

[arkanoid]

OK - although the first post reads as though that's actually what you were asking.

No, just which marking on these speakers should be treated as RMS. Thanks

 

[nopiano]

Given the low sensitivity (85dB) 50W for a new amp seems like a safe minimum.

I would say maximum, not minimum. But if your aspirations are to get proper Hifi speakers, rather than the gloried cornflake boxes that most music centres had, then just choose an amplifier you like and exercise restraint with the current speakers.

An obvious choice would be the ever popular Marantz PM6007, or similar models by Cambridge, Rotel (the magazine likes their new A8) or Denon.

Marantz PM6007 review

What Hi-Fi? Awards 2023 winner. Marantz refines its hugely capable budget amp recipe

www.whathifi.com

 

[Stuart83]

Might happen almost never with modern speakers, but that's not my case.

My speakers are only 85dB, so that's why I'm trying to determine their RMS.

It's only a fairy tale until it happens to you.
Some of you remember the pics and teardown of me clipping some mission mx3's into total seizure on all four drivers using a known overrated underpowered amp with too much gain via Bluetooth.

Given the right conditions clipping can occur with any speakers.

I haven't got time to go further into what you already obviously know so apologize for being lazy and using a multi quote of the older post but you do right on airing on the side of caution.

I think people get confused with wattages, there's many other factors to consider and clipping is rare but very real.

"A real world insight" and perhaps to put your mind at rest 😜 is It's always better to have more power than too little.
One can always turn it down a little but you can't turn an underpowered amp up over it's limit and it's dangerous when approaching it.

Contrary to belief and underpowered amp is more dangerous than one with too much power when used sensibly of course.
For haste and as it mirrors my understanding and experience only recently when severely damaging a pair of mission floorstanders on all four drivers causing both warping and burning out (see attached pictures) I'm pasting in Google's AI.

"An underpowered amplifier can clip and damage them:
Clipping
When an amplifier is underpowered for the volume setting or speakers, it can clip, which generates square waves.
Damage
These square waves can burn out the speaker's high-frequency driver because of the extra high-frequency harmonic content"

To avoid clipping, make sure the amplifier matches the speakers and desired volume levels. You can check the amplifier's speaker impedance range, which is usually printed near the speaker terminals. For example, an amplifier might be compatible with 4-8Ω speakers.

I only play at loud volumes having the luxury of living in a semi detached bungalow set away from other houses.
I only go for amps north of a genuine 100w to make sure I have plenty of headroom despite knowing with adequate current 60W can get most speakers to open up nicely.

Over the yrs I've managed to damage a few pairs of speakers but find quality gear lasts.
There's obvious and quite dramatic telltale signs when your pushing too far.

Audible Distortion is the biggest give away which is unmistakable when up there in the danger area it comes along side almost lisping treble highs that will make most wince.

The more concerning silent killers are clipping which with certain genres is hard to spot especially if not paying much attention with busy lively music masking things.
The heat build up over time causes warping and blistering to the inner coils and consequently a malformation in the speaker thow.
This causes the scratching to the inner coil in the pictures when rubbing up against the core until they completely seize up.

This can happen over time silently as I found, cranking up the clash with too much gain from my Bluetooth connection was the speakers last few death throws pardon the pun.

The other failures I've had where more common in djay gear which was a regular occurrence but at home over the yrs another 2 pairs of missions bit the dust, one with a torn spider but at 33yrs old of playing loud music it's testament to how well made they were and it wasn't because of anything but age with them.
The others were my first ever bought speakers with the rubber surrounds wearing out again at 20 plus yrs of loud music.
Even a pair of old tannoy M15's took abuse for 20 plus yrs before an accidental knock to the tweeter caused them to disintegrate after time.

I mention this off point as with the correct pairing even small speakers can take a battering but none are indestructible.
If the specs in ohms are matched with quality gear then too much power isn't a problem as the volume dial therefore "power" is at your commands.

 

[arkanoid]

exercise restraint with the current speakers.

It would say that's rather obvious

 

[Al ears]

No, just which marking on these speakers should be treated as RMS. Thanks

None. Speakers have nothing to do with RMS which is an output measurement of an amplifier.

 

[arkanoid]

None. Speakers have nothing to do with RMS which is an output measurement of an amplifier.

RMS is used for speakers' rated power on a daily basis. Correctly to the definition or not, it is often used.

 

[Al ears]

RMS is used for speakers' rated power on a daily basis. Correctly to the definition or not, it is often used.

Can you provide an example?
We are talking about passive speakers here mind you.

 

[arkanoid]

Can you provide an example?
We are talking about passive speakers here mind you.

Yes, I'm referring to passive speakers.

As for the examples - speakers' product pages and HiFi enthusiast websites.

PRO-X 6.5" Mid-Range Bullet Loudspeaker 250 Watts Rms 4-Ohm

Shop online DS18 PRO-X6.4BM 6.5" Mid-Range Loudspeaker with Bullet 500 Watts 4-Ohm. Free shipping on all U.S. orders.

ds18.com

What’s the Difference Between RMS and Peak Watts?

Understanding root mean square (RMS) and peak power ratings is essential for building a high-performance entertainment system. Learn what these power-handling terms mean to make...

www.mwrf.com