Not enough power from my amplifier?

misfits73

Member
2012-09-26 6:08 pm
Hi chaps,
a quick technical one:

I bought a pair of celestion ditton 332, connected them to my NAD 3130 but the sound is very flat, almost no bass in low volume.
When I press the loudness button on my amp the speakers get alive and sound as they should be.

Does that means my amp is not capable to drive properly the dittons?
Not enough current for 10" woofer, 5" midrange, 3" tweeter, 8 Ohms impedance (can't find their sensitivity) ?

Cheers
 

Mooly

Administrator
Paid Member
2007-09-15 8:14 am
That's not a lack of power because switching in the loudness actually increases the voltage drive to the speakers.

It sounds more like a characteristic of the speakers tbh.

Easiest solution is to try another amp.

To prove it definitively requires a scope (or suitable DVM) and some test tones on CD at known level and different frequencies or better still a frequency sweep (easy to make such a CDR with Audacity). Then just check the output of the amp is constant at all frequencies.
 
The technical part was if the loudness increases current or voltage


That is not what you asked. But the answer to that question is it increases both current and voltage requirements. If your "loudness" control provides 4 dB of bass boost, this in effect reduces the efficiency of your speakers to around 86 dB with 2.8 watts input, or around 82 dB/ watt. This means that with your "loudness" button on you would require about 60 watts to drive the speaker to 100 dB with zero headroom. (This is for one speaker; add 3 dB and double power for 2.)

So a ball park figure is that a 60 watt/channel amplifier would produce 103 dB SPL with zero headroom. I hope this helps.
 
Last edited:
Shall I consider them scrap already?lol

No, you just have to understand what you have.

In my experience, low efficiency speakers exhibit significant dynamic compression. There are always exceptions. I am not familiar with this particular speaker, but apparently it is somewhat popular so it may have merit.

My ballpark figures above do not take into account this dynamic compression, which may be as little as 2-3 dB (excellent) to 7-10 dB (poor).
 

Ian Finch

Member
Paid Member
2010-04-11 4:22 am
Coffs Harbour, NSW
FWIW, NAD 3130 is yet another version of the 3020, a good sounding but pretty anemic amp when it comes to driving deaf speakers
like these Celestions. Having scanned a few reviews and realised there are conflicting specs, the description "handles extreme power levels" triggered the idea that these could need a big amp with plenty of capability into low impedance loads - perhaps as you found by hooking up up to your HT amp.

This brings up the question of what speakers you used with the NAD previously or is all this gear new to you?
 

Mooly

Administrator
Paid Member
2007-09-15 8:14 am
Connected them to my AV receiver, Marantz NR1602 in direct mode, sound better imho.

I was confused about that 2.8W at 90db, how much is really?

Shall I consider them scrap already?lol

Sounds better imho :)

That comes across as a very "subjective" comment tbh... which is fine... but seems to imply that there is "still no bass" at low volume. Otherwise I think you would be saying "yes, the NAD must have a problem"
 

misfits73

Member
2012-09-26 6:08 pm
This brings up the question of what speakers you used with the NAD previously or is all this gear new to you?

My NAD works fine with my B&Ws 602 S2.

The whole idea started when I got another amp, the JVC JA-S22, it was very cheap.I started looking for some old speakers to pair with it (the 602s sounded bad with the JVC) in order to revive the '70s-'80s sound I like.

I found these Dittons and I grab them, that's the whole story.
The JVC is rated for 40W @ 8Ohms and sounds slightly better than the NAD. That's why I assume I need a bigger amp.

Bear in mind that for the money i paid everything is in mint condition, bargain.
 
Yes but :
I cannot enjoy music without loudness set to on, I know that people hate that button, some amps don't even have tone controls for pure audio;it ruins the sound

What can I do in my case?

People hate that button sometimes because it usually doesn't work very well. It usually gives too much boost for medium or high efficiency speakers. It sounds like with your combo it's right on the money. You should be happy.

Can you explain to me, based on your own experience and perception, how tone controls "ruin" the sound? Some tone controls are in fact terrible, but some are OK.

It's not necessarily the equipment that neccesitates the use of tone controls; it's our nonlinear hearing and subjective perception that requires them. Room acoustics play an important part too.

If you want "pure" sound without needing tone controls, open your wallet and have a custom designed system installed in a dedicated, acoustically adjusted room. Otherwise, tweak what you have until it sounds good to you.

Bear in mind that for the money i paid everything is in mint condition, bargain.

There's nothing wrong with that.
 
Just to prove (or otherwise) that the sound from the speakers is the same with a different amp.

This would most likely be the case.

missfits73... to see how much power (voltage
AHsJFJhC1JVdTiwNFHjIzQRYghQooATggIBTTTRlyNVL0Z4COQLoGuCnQgAduFxBEWgoDaMibGzFWSPmU4csj+wM1PKj1okIIUjp6WEESB+BGGKhQHUrj5U6CaosGTVmjgxZfDhtogIpxgAJAgBgmZTpC5kNAxkcmaIq1B1PgSotWCgQzyIagHx4afCnFZqFdF5IKWCKgGENQxAxKdGi1yBCpWrMCCDCAC0TAdrsuGRDyAcYFIJ0QSDAAIIEiQBEYpWEh5JXTySZAQBmxYADD8KQaOQCTi8cXFZ5cGRBDYRUZd6AuiFnIIhOW1QQucCBFxJMLM7QFTgiioNZheYuAgwIADs=
) you really need, try this,

http://www.diyaudio.com/forums/multi...kers-need.html

Everybody should do this.
 
My living room had become a music lab with the amps,speakers cables etc.
I was switching between the Dittons and B&Ws to check which one makes a good pair with the amps.
My cd player was not connected during listening, no more space i said....
Don't make me tell you the source i was using,i thought it made no difference, how stupid i was.

Everything is ok now,the Dittons kick major as***s

Sorry for wasting your time replying, at least this forum always gives me something to experiment of.Besides i learnt a lot today.

Any moderator to delete my thread before other people see it and start laughing ?

Regards