speakers Speaker assistance - distortion (pre amp or speakers?)

[Daniel Delindi]

hi guys 
 

Part of my passion in loudspeakers, apart from enjoy listening to speakers - and appreciating Good sound, is knowing a speaker has power and authority. I don’t necessarily like to play very loud for more than 10min, but I do sometimes after a hard day at work - and I want to have the confidence that a speaker can handle the power.

 

In saying that I have bought a 220RMS Anthem power amp - MCA30 connected to a seperate pre amp - A Cambridge 851A. I know this is an integrated not a dedicated pre amp - however i am using as a pre amp. Connected to the pre amp 851A is a Cambridge dac magic and connected to my laptop via USB and played via iTunes or Tidal.

I noticed, not on my 10” Ascension floortsranders  but only on my bookshelfs 140RMS Rated Ascenion bookshelfs (used a satori 7.5” bass driver) that there is slight distortion on the bass driver only, not the mid - only on certain songs.. This is at a volume that is not far from the pre amp clipping-1.

My question is that I do not know if it is the pre amplifier that is clipping, or if it is the Speaker not being able to handle the load.

It sounds as if the speaker can not handle the load and a slight pop sound from the speaker - but it’s odd because it’s only on one song.

My 10” ascenion is fine handling the same gain on the amp - so I’m thinking that it might be the fact the bookshelf may not be to handle the power? Particularly the bass driver?

 

if anyone would know whether I just need a more powerful speaker (which makes sense as the amp is 180rms @ ohms) and my speakers are rated at 140rms and are 8ohm speakers.

 

if anyone can help a beginner like me that would be greatly appreciated

 

thanks

daniel 

[RCAJack]

As you say, seems the amp is pushing the bookshelf speakers too hard. Ratings aside, if you can hear distortion and popping noises, then it’s time to back off or risk causing damage! 
 

BTW I think you could run the dac directly into the power amp and use the laptop as a volume control? I don’t think it’ll help this problem but maybe could satisfy your curiosity about the role of the Cambridge. Note you should make sure dac and laptop are connected and on before power amp is switched on. 

[stereo coffee]

The specifications of your power amp is here:   https://www.hifiengine.com/manual_library/anthem/mca-30.shtml

Compared to this one:   https://www.hifiengine.com/manual_library/quad/909.shtml

 

The anthem mca-30 has ... 10 x the total harmonic distortion figure, so the distortion you are hearing may be attributed there, but lets look also at a few other areas.  Simple things like checking your speaker cables are tight in their fittings at each end can prove very beneficial.

 

Strange as it seems, we tend to hear other components distortion before that of loudspeakers. David Blackmer founder of DBX describes it here:

 

What is the piece of music you hear said distortion with ? Whilst rarely discussed, there is occasionally incompatibility of level during recording, that then transpires as distortion when played back at consumer line level. The second video discusses the recording side to enable dynamic range, but then reduce level for playback in consumer equipment. Your CD may have such a incompatibility, inviting it is not the amplifier or loudspeaker at all.  A few of us perhaps might be able to test the same piece of music for you.

 

 

 

 

 

 

 

 

[Daniel Delindi]

Thanks for replying stereo coffee

 

it is the bass driver being pushed and moving , and People could call me silly but I’m driving my speakers very hard. But it’s the volume I like. 
however I have a 200watt speaker that is actually has a higher sensitivity rating, with a 10” bass driver rather than a 7.5” bass driver and not only is it much louder on the amp at the same volume - but you don’t hear any distortion on the 10” driver. The 7.5” is moving a lot more and you hear a slight pop - from reading this is the cone smacking the driver which is obviously doing. But it’s so subtle I want to know how to get very loud volume.

do I buy an amp with lower harmonic distortion or do I buy a more efficient or power rated speaker ?

 

to put things into real world examlr

my bookshelf is a 3way speaker with a 7.5” SB acoustics Satori bass driver. The complete speaker is rated at 140Rms 

 

my 10” speaker has a BandC driver which is more a PA type driver with shorter voice coil. 
 

I guess my question is. Can I achieve the same volume without my bookshelf popping by choosing an amp with lower harmonic distortion ?

 

[muon*]

If you want louder use speakers that are more sensitive and can go louder, like the floorstanders you have.

 

Edit: if you are pushing the standmounts to the point where you are hitting the excursion limit of the Satori driver stop doing that, and a different amp will likely not help you.

 

You likely need speaker that are more sensitive, but also that pressurise the room more, so that means larger cone area, so larger drivers or more of them. 

 

Do you use a sub woofer with the standmounts?, if not maybe that would help tame your propensity to turn them ups so high that you might damage them (not to mention damaging your hearing)

 

Edit: on reflection I may not correctly understand what the issue here actually is.

Edited May 23, 2021 by muon*

[warweary]

Pops are annoying. A few diagnostic questions...

 

Which song? About what time in the song?

Have you tried different versions of the same song to see if its a recorded sound and reproduceable?

Is the pop from the left channel or right or otherwise?

If you are able to use an analogue source (with same song) into the integrated, does the pop happen still?

Try running the dac magic straight into the anthem power amp and see if the issue remains. Be careful with the software volume setting as the gain will likely be different compared to the preamp in the ca integrated.  Does the issue remain or get worse or?

 

buuuutt maybe all u gotta do is play that loud only on the floorstanders.

[Daniel Delindi]

The song is superfly sister - Michael Jackson 

i play many songs with bass and they are fine. This song getting to about to 86/100 volume on the Cambridge and you hear a slight pop

 

to be honest it’s very loud and not practical to have it this loud, I just I want to know is it really my speaker that’s making the sound or some kind of distortion from the amp, source, quality, cabling. I know it’s hard to answer - I guess I just like having the confidence my speakers can handle the power...but I guess they can’t.

 

i guess if I like to play really loud after work at times, I’m better off with high sensitivity speakers. Perhaps something like 97db sensitivity rating.

[muon*]

If it is the excursion of the driver hitting the limit if the same speakers happened to be more sensitive it would just mean you would hit the excursion limit sooner, It's a bit more complex.

 

Honestly, if at your normal listening levels this is not happening then they are handling things just fine.

[almikel]

On 24/05/2021 at 12:06 AM, Danny525 said:

but you don’t hear any distortion on the 10” driver. The 7.5” is moving a lot more and you hear a slight pop

sounds like you're "poling" the 7.5" driver - ie exceeding Xmax and hitting Xlim, the mechanical limits of the driver, which is bad

 

You need to investigate speakers and amps (together) that can reach your SPL requirements "in room" without your speakers or amps exceeding their limitations (ie speakers not exceeding Xmax and amps not clipping).

 

A 10" mid bass driver will struggle to produce decent SPL down to 40Hz, a 7.5" driver more so

If you like it loud, then a sub is required with an appropriate crossover so your mains don't have to handle the low end at high volume.

 

33 minutes ago, Danny525 said:

I’m better off with high sensitivity speakers. Perhaps something like 97db sensitivity rating.

not necessarily

 

Although I would always suggest higher sensitivity speakers over lower sensitivity speakers, in your case you need speakers and amps that can meet your "in room" SPL targets (eg loud).

 

A speaker's sensitivity is not directly related to it's SPL capability.

 

If you like it loud then size matters - a 10" driver will have to move less than a 7.5" driver to create the "in room" sound at all volumes, but as the SPL increases a 7.5" driver will run out of excursion sooner than a 10" assuming they have similar Xmax.

 

For exemplary mid bass performance IMHO the Acoustic Elegance TD18s are hard to beat - 14mm Xmax and 98dB/1W/1m - 18" mid bass is killer. 

 

Maybe smaller mid bass drivers can cut it - I love my TD18s - they barely move at extreme volumes...but they're crossed to a sub underneath... 

[stereo coffee]

I would try filling the rear mounted rectangular port on each speaker with a few socks or similar blocking material. Acoustic suspension remains IMO the best way of reducing distortion in bass drivers.  https://en.wikipedia.org/wiki/Acoustic_suspension

[Daniel Delindi]

Hi Guys

i have an update

i got rid of the Cambridge 851A and using a Yamaha R-S700 to test this issue as both the main amp and pre amp

 

so what is funny is that distortion sound I am referring to is still evident on the Anthem connected to the Yamaha.

however if I play the Yamaha on the same exact level/DB , say +2DB on the amp - you do not hear this popping noise.

 

..Now I’m beginning the think it’s the anthem the whole time and it’s to do with its 1% percent THD rating, where this yamaha is rated at 0.019

im comparing a 100Watt amp to a 180watt amp , but then volume is not far off and you don’t hear this noise 

 

if anyone can listen to superfly sister - Michael Jackson and crank it perhaps it might explain/describe What I’m referring too

 

i also listened very closely and this slight distortion noise when playing at very loud volumes  is still showing on my 10” Ascension speakers, but more evident on the 7.5” Bookshelf ascensions. I’m thinking now it’s a combination of the amps THD and speaker?

 

no problem goes away when I use the Yamaha, but that could obviously be not because it has lower THD but because it’s just less powerful. 
such a shame because the Anthem sounds really nice, just when I crank it on this one song I hear distortion!

[almikel]

any "popping" sound is bad - based on your post it sounds like something in your pre-amp/amp chain rather than poling your speakers (ie hitting Xlim)...

 

31 minutes ago, Danny525 said:

..Now I’m beginning the think it’s the anthem the whole time and it’s to do with its 1% percent THD rating, where this yamaha is rated at 0.019

no - your ears aren't capable of differentiating 1% THD vs 0.019% THD, unless the distortion is very high order - focus on the pops - an amp is clipping or a driver is poling.

 

42 minutes ago, Danny525 said:

no problem goes away when I use the Yamaha, but that could obviously be not because it has lower THD but because it’s just less powerful. 
such a shame because the Anthem sounds really nice, just when I crank it on this one song I hear distortion!

Amp specs on THD go out the window when the wick is turned up...they get way higher...but THD has been demonstrated as not a good metric for sound quality (reference Toole, Geddes et al...)...THD is arguably not audible until way higher than modern amps produce.

 

You're comparing the output from small drivers (7.5") with a bit bigger small drivers (10")...both would have significant distortion if asked to generate lowish bass at highish SPL...way more distortion than the THD on your amp (but I accept at a lower order than the distortion of your amps).

 

...your electronics won't be the issue, unless you're clipping an amp.

 

High SPL at frequencies <100Hz requires decent cone radiating area plus a sub - stereo 10" plus a sub is likely fine, maybe even stereo 7.5" plus a sub would work.

 

Without a sub to manage below 80Hz or so, a 10" will struggle to get low enough and a 7.5' will struggle more.

 

cheers,

Mike

[Daniel Delindi]

I think I’m clipping the amp. I retested on a few songs , and on all of my three speakers increasing JBL S310, I hear distortion. My 10”‘ascension use 10 b&C bass driver rated at 150rms (300 peak) and overal speaker rating including all 3 drivers is 200rms

 

when I go +4.5Db on the pre amp; it is extremely loud - I’m talking party loud - uncormfortble for regular listening. Isn’t it something like double wettage per 3DB. I’m assuming 0db on the Yamaha S-700 (used as a pre amp) and would be max volume, so plus 3DB would = 200 watt ?

and my anthem MCA 30 is 180RMS it could maybe be clipping ?

[warweary]

On 27/05/2021 at 10:16 PM, Danny525 said:

Hi Guys

...

if anyone can listen to superfly sister - Michael Jackson and crank it perhaps it might explain/describe What I’m referring too

 

Yo.  I cranked, any reason for a quick loud session I say.  Was peaking at 106 db at just less than 1 m from the speakers, average 1 minute db was 98 db.  Just sounded good to me, no noticeable cracks or pops, just the music.  That's as loud as I'll go.

 

[muon*]

39 minutes ago, Danny525 said:

I think I’m clipping the amp. I retested on a few songs , and on all of my three speakers increasing JBL S310, I hear distortion. My 10”‘ascension use 10 b&C bass driver rated at 150rms (300 peak) and overal speaker rating including all 3 drivers is 200rms

 

when I go +4.5Db on the pre amp; it is extremely loud - I’m talking party loud - uncormfortble for regular listening. Isn’t it something like double wettage per 3DB. I’m assuming 0db on the Yamaha S-700 (used as a pre amp) and would be max volume, so plus 3DB would = 200 watt ?

and my anthem MCA 30 is 180RMS it could maybe be clipping ?

Clipping is usually audible through the tweeters as a high frequency distortion/break up.

 

I don't understand why you are driving things to levels where listening is uncomfortable. 

[muon*]

https://en.wikipedia.org/wiki/Clipping_(audio)

[Guest dr_carl]

Very high volumes stimulate release of adrenalin,  and it may be that adrenalin is what you crave. You will be causing irreversible ear damage listening at the levels you report. Be careful or you will have to cope with either hearing loss or tinnitus. 

 

Pushing your gear so hard just does not sit well with me. You will damage the speakers even more, and perhaps the amp too.

 

Maybe you should try to find your sweet spot where it all comes together...which may be more in 85 dB area than the 100+ dB danger zone.

 

I don't mean to sound patronising but please don't go deaf having fun.

[almikel]

On 30/05/2021 at 4:41 PM, Danny525 said:

Isn’t it something like double wettage per 3DB

"wettage" I'm not sure of, but yes, increasing the amplifier output by 3dB doubles the power output required.

Add another 3dB (ie total of 6dB) quadruples the power required - which is why EQ can easily run amps into clipping - every 3dB doubles the power required.

 

On 30/05/2021 at 5:11 PM, warweary said:

Yo.  I cranked, any reason for a quick loud session I say.  Was peaking at 106 db at just less than 1 m from the speakers, average 1 minute db was 98 db.  Just sounded good to me, no noticeable cracks or pops, just the music.  That's as loud as I'll go.

plenty loud enough for home environments for short periods...we need to consider our neighbours and other house occupants unless we have a very well isolated room.

 

4 hours ago, dr_carl said:

Maybe you should try to find your sweet spot where it all comes together...which may be more in 85 dB area than the 100+ dB danger zone.

If I'm in the mood for a loud listening session, 85dB won't cut it, and I choose to play it louder than that when in the mood for crankin'...

...and I understand the risks/damage caused to my ears, so I choose to keep those "elevated SPL" sessions infrequent and short...accepting "elevated volumes" are damaging my hearing.

 

I'm the guy that always wears hearing protection when mowing the lawn - if I'm going to damage my ears I prefer to do it listening to loud music ,

 

cheers

Mike