So, I messed up a little...

[CGMe]

Lately I've been throwing some little upgrades at my Pro-Ject Debut Carbon EVO. The original wall-wart has been replaced with an Ifi power supply and last week I replaced the Ortofon 2M Red stylus with a Blue one. Obviously it isn't night and day, there are some noticeable differences. Mostly in what you don't hear. The low hum and hiss from just having the phono input selected is gone due to the power supply and the 2M Blue stylus seems a bit better a picking up lower volumes. They are more clear now and slightly less noisy.

So, yesterday I was playing Hans Zimmer's Interstellar soundtrack on vinyl. Side B track 3, 'Mountains' has a deep low rumble which was produced by a large church organ. Right from the start of the track you see the drivers moving (alot!) without hearing the produce an audible bass. It's well below what my speakers are designed to produce. This track just begs for some more volume and the dial of my Cambridge 851W went to -30 dB. It's been at that volume more often, so no issues there. I thought...

About halfway into the track one of my speakers suddenly sounded distorted. Oops. It appears the mid-bass driver on one of my Focal Chora 816 is now damaged. Nothing visible, but there is now some audible distortion on all volumes, and a slight scraping mechanical noise at a bit louder volumes.

Amp recommendation on the Chora 816 is 40-200 Watt. The Cambridge 851W is specced at max. 200W at 8 Ohm. I (wrongly) believed that I was safe cranking up the volume, but apparently that's not how it works. Low frequencies combined with higher volumes can make the impedance dip lower. So at 4 Ohm the Cambridge delivers 350W, which is a lot more than the Chora 816's can handle. Again, oops.

So I've now mailed Focal support, hoping it's possible to get (buy) a replacement driver so I can service the speaker myself. Fingers crossed.

 

[Al ears]

Cone flap is quite common on ported speakers and amplification that has no susonic filter unfortunately.
A cartridge change can help but not in extreme cases.

 

[daytona600]

drivers moving (alot!)
Sounds like feedback / rumble woofers will move a lot on reflex ported speakers
can you move TT away from speakers , or place on hifi rack / wall shelf / isolation platform
Organ on interstellar is immense & contains subsonics & would require multiple 12/15inch drivers & several thousand watts to re-produce

project WMI Rack 5/4

 

[My2Cents]

As AI stated, the low rumble from the church organ is not what was producing the woofer pumping, it was subsonic frequencies being produced, most likely by poor speaker/turntable placement in the room and possibly poor installation of the cartridge and set up of the tone arm.
Many amps. have a certain degree of subsonic filtering built in, but not all do and it varies as to how much they can filter out.
The project WMI Rack (pictured in post #3) is not the best solution either. It is screwed to studs (or just simply straight into the dry wall/plasterboard with drywall anchors) and the TT may very well still pick up a LOT of low frequency vibration through the wall which will still get transferred to the TT.
Ideally the TT should be placed on a very heavy plinth and in another room or basement if possible.
I once saw a guy who had his TT on a concrete slab in his basement and he ran the cables up through the floor to the TT in the room above (which avoided a long cable run).
Bass nodes are created around the room and if you happen to place the TT in one of these 'node' areas it will exacerbate subsonic problems. Carefully placed bass traps are another thing to consider.

 

[Al ears]

As AI stated, the low rumble from the church organ is not what was producing the woofer pumping, it was subsonic frequencies being produced, most likely by poor speaker/turntable placement in the room and possibly poor installation of the cartridge and set up of the tone arm.
Many amps. have a certain degree of subsonic filtering built in, but not all do and it varies as to how much they can filter out.
The project WMI Rack (pictured in post #3) is not the best solution either. It is screwed to studs (or just simply straight into the dry wall/plasterboard with drywall anchors) and the TT may very well still pick up a LOT of low frequency vibration through the wall which will still get transferred to the TT.
Ideally the TT should be placed on a very heavy plinth and in another room or basement if possible.
I once saw a guy who had his TT on a concrete slab in his basement and he ran the cables up through the floor to the TT in the room above (which avoided a long cable run).
Bass nodes are created around the room and if you happen to place the TT in one of these 'node' areas it will exacerbate subsonic problems. Carefully placed bass traps are another thing to consider.

Sounds a tad extreme and not really necessary. I prefer a turntable in my listening room....
Mine current is and is even on the same rack as my amp with absolutely no issues....
Much is down to the nature of the arm / cartridge/ and the phono preamp

 

[Gray]

....there is now some audible distortion on all volumes, and a slight scraping mechanical noise at a bit louder volumes.

"First the bad news....there's no good news" 😆

Sorry, it's not funny.
You've learned that those frequencies you see rather than hear, are bad news.

Nobody likes spending unnecessary money less than me - but I don't think I'd be replacing only the driver that is obviously faulty. At least 2 (if not 4) of them got a taste of your punishment).

And I know for sure that I wouldn't be playing such special effects type tracks at high levels into the repaired speakers.
(It's why soundcheck discs come with a volume level warning).

 

[My2Cents]

There is nothing in the track that you mentioned that goes down even close to 20Hz.
Due to RIAA vinyl mastering standards, any frequencies that made your speakers flap that badly were being created by your system set up/placement of gear and not from the vinyl pressing.
I just listened to the track at high volume (streaming FLAC from Qobuz at 24/44.1) with my sub turned up and there is no deep bass at the start of that track. Seeing your speakers move like that and then turning UP the volume was, as you stated, "messing up a little".
I would have stopped the playback and investigated the problem.
Sadly for you, I think Gray is correct.
You mention in your signature that you have QA 3050's? Are the Focal's new?

 

[CGMe]

First of all, thank you for your replies. All the explanations of it probably not being in the track but in the setup actually makes sense, when judging by your information.

• The Pro-Ject Debut Carbon EVO is a pretty light-weight turntable without heavy plinth.
• The turntable is placed on a regular cabinet, not rigid or particularly sturdy
• The base floor in the room is wood, on wooden beams. On top of this there are interlocking fiber panels with a PU cast floor. Under the floor is a crawl space. So nothing rigid like concrete.
• Left speaker is about 40 cm from the turntable
• Right speaker is about 2 meters from the turntable. It was the right speaker that was heavily flapping and is now broken
• Phonostage, pre- and poweramp are on platforms placed under the cabinet. On the floor. The platforms have somewhat isolated feet, but nothing really fancy.

Based on the information you guys told me, these all can be variables of introducing resonance of some sort. Never really gave it all that much consideration. Lesson learned. First priority is to see whether I can get the speaker fixed so I can at least stream again without extra noises from the speaker cabinet. Had an autoamated reply from Focal support already that my case has been forwarded to the local distributor Latham Audio in the Netherlands. Really looking to try and fix only what's broken, because of budget. First have to see what my options are.

The QA 3050's were indeed recently replaced with these Focals which I could get for a decent secondhand deal. My signature should now be updated now with the correct speakers (and cartridge). Also added the phonostage, since I noticed that was missing.

Regarding tackling the issue that caused this. Obviously it being a Project Debut I can't really do much about the weight of the turntable. Don't believe there's a lot I can do about tonearm adjustments with the Carbon EVO too, but please correct me if I'm wrong. I guess I could move the turntable a bit further away, together with the phonostage and use a long interlink to the amp. Length would be close to, or just over 4 meters, so I guess XLR would be beneficial here? Current phonostage is RCA only.

This is a photo of the current situation. As you can see, not really ideal. I might be able to make a place for the turntable somewhere in the space on the left of the picture.



Any other suggestions I can look at, without the obvious being to replace the cabinet with a proper audio rack?

 

[Al ears]

First of all, thank you for your replies. All the explanations of it probably not being in the track but in the setup actually makes sense, when judging by your information.

• The Pro-Ject Debut Carbon EVO is a pretty light-weight turntable without heavy plinth.
• The turntable is placed on a regular cabinet, not rigid or particularly sturdy
• The base floor in the room is wood, on wooden beams. On top of this there are interlocking fiber panels with a PU cast floor. Under the floor is a crawl space. So nothing rigid like concrete.
• Left speaker is about 40 cm from the turntable
• Right speaker is about 2 meters from the turntable. It was the right speaker that was heavily flapping and is now broken
• Phonostage, pre- and poweramp are on platforms placed under the cabinet. On the floor. The platforms have somewhat isolated feet, but nothing really fancy.

Based on the information you guys told me, these all can be variables of introducing resonance of some sort. Never really gave it all that much consideration. Lesson learned. First priority is to see whether I can get the speaker fixed so I can at least stream again without extra noises from the speaker cabinet. Had an autoamated reply from Focal support already that my case has been forwarded to the local distributor Latham Audio in the Netherlands. Really looking to try and fix only what's broken, because of budget. First have to see what my options are.

The QA 3050's were indeed recently replaced with these Focals which I could get for a decent secondhand deal. My signature should now be updated now with the correct speakers (and cartridge). Also added the phonostage, since I noticed that was missing.

Regarding tackling the issue that caused this. Obviously it being a Project Debut I can't really do much about the weight of the turntable. Don't believe there's a lot I can do about tonearm adjustments with the Carbon EVO too, but please correct me if I'm wrong. I guess I could move the turntable a bit further away, together with the phonostage and use a long interlink to the amp. Length would be close to, or just over 4 meters, so I guess XLR would be beneficial here? Current phonostage is RCA only.

This is a photo of the current situation. As you can see, not really ideal. I might be able to make a place for the turntable somewhere in the space on the left of the picture.

View attachment 6340

Any other suggestions I can look at, without the obvious being to replace the cabinet with a proper audio rack?

 

[Al ears]

Thanks.
It seems fine to me. Perhaps some isolation platform under the turntable itself.
Some speakers are more prone to cone- flap than others.
Is it just this LP that has issues or all of them?

 

[My2Cents]

You purchased these used, correct?
I'm guessing Focal will direct you to your local repair facility somewhere in the UK.
If used, I doubt that it will be covered under warranty.
Shipping (or 'carry in' if you are close enough), diagnosis and final repair is most likely going to be eye wateringly expensive. Focal's replacement drivers are notoriously pricey, even for their budget range.
It's probably going to be cheaper to buy another secondhand pair

You say you have a phono stage? You could research using a sub sonic filter between it and the amp input for future protection (unless it already has one or there may be a switchable/adjustable one in the amp)?

 

[Fandango Andy]

First of all, thank you for your replies. All the explanations of it probably not being in the track but in the setup actually makes sense, when judging by your information.

• The Pro-Ject Debut Carbon EVO is a pretty light-weight turntable without heavy plinth.
• The turntable is placed on a regular cabinet, not rigid or particularly sturdy
• The base floor in the room is wood, on wooden beams. On top of this there are interlocking fiber panels with a PU cast floor. Under the floor is a crawl space. So nothing rigid like concrete.
• Left speaker is about 40 cm from the turntable
• Right speaker is about 2 meters from the turntable. It was the right speaker that was heavily flapping and is now broken
• Phonostage, pre- and poweramp are on platforms placed under the cabinet. On the floor. The platforms have somewhat isolated feet, but nothing really fancy.

Based on the information you guys told me, these all can be variables of introducing resonance of some sort. Never really gave it all that much consideration. Lesson learned. First priority is to see whether I can get the speaker fixed so I can at least stream again without extra noises from the speaker cabinet. Had an autoamated reply from Focal support already that my case has been forwarded to the local distributor Latham Audio in the Netherlands. Really looking to try and fix only what's broken, because of budget. First have to see what my options are.

The QA 3050's were indeed recently replaced with these Focals which I could get for a decent secondhand deal. My signature should now be updated now with the correct speakers (and cartridge). Also added the phonostage, since I noticed that was missing.

Regarding tackling the issue that caused this. Obviously it being a Project Debut I can't really do much about the weight of the turntable. Don't believe there's a lot I can do about tonearm adjustments with the Carbon EVO too, but please correct me if I'm wrong. I guess I could move the turntable a bit further away, together with the phonostage and use a long interlink to the amp. Length would be close to, or just over 4 meters, so I guess XLR would be beneficial here? Current phonostage is RCA only.

This is a photo of the current situation. As you can see, not really ideal. I might be able to make a place for the turntable somewhere in the space on the left of the picture.

View attachment 6340

Any other suggestions I can look at, without the obvious being to replace the cabinet with a proper audio rack?

If your floor is bouncy, your best option is probably a wall shelf, if that's a solid wall. If it's a stud wall then there probably isn't any benefit.

If you don't have floor bounce just go for an isolation platform. They are commercial available or you can make your own. Get a set of isolation feet and attach them to a board. Two best options for the board is big and heavy such as a butchers block chopping board, or dense and dead, such as the the thickest piece of MDF you can get your hands on.

 

[Gray]

Really looking to try and fix only what's broken, because of budget.

I don't blame you for that

I'm assuming you will be doing your own driver replacement and, with luck, only the lower of the two drivers in the right speaker will need replacing.

You know what you've heard, but to put your mind at rest, you could do a basic check of all 4.
With the power off, gently push each cone in and out.
It's essential to push with even pressure, ideally with fingers either side and around the junction of dustcap and cone.
There should be a very obvious scrapy feel to the faulty one - and hopefully all 3 others will be fine.

If you do the job and remove the scraper, then it can become the subject of a post mortem procedure.
(I used to examine scrapers in a service department. There's something that feels very wrong when cutting into a cone with a scalpel - especially on an expensive 18" bass driver - but scrapers are good for little else).
When you remove the voicecoil from the gap in the magnet, you'll soon confirm the cause of your scrape - and you'll see where your excess bass energy went.

Good luck in sorting things out.
I wouldn't bother with the expense of balanced phono stages.

 

[CGMe]

Thanks.
It seems fine to me. Perhaps some isolation platform under the turntable itself.
Some speakers are more prone to cone- flap than others.
Is it just this LP that has issues or all of them?

I've never noticed the cone flap before, but to be really honest Im not 100% sure whether it only occurs when playing vinyl. I might into getting an isolation platform fot the turntable.

You purchased these used, correct?
I'm guessing Focal will direct you to your local repair facility somewhere in the UK.
If used, I doubt that it will be covered under warranty.
Shipping (or 'carry in' if you are close enough), diagnosis and final repair is most likely going to be eye wateringly expensive. Focal's replacement drivers are notoriously pricey, even for their budget range.
It's probably going to be cheaper to buy another secondhand pair

You say you have a phono stage? You could research using a sub sonic filter between it and the amp input for future protection (unless it already has one or there may be a switchable/adjustable one in the amp)?

That is correct. And in my message to Focal I let them know I don't really expect a warranty because of them being secondhand and the fact that it's most likely a user error on my side. I specifically inquired whether the speaker would be self-serviceable.

I've just been looking into the subsonic filtering. First of all, my Vincent phono stage doesn't appear to have one. Obviously. Might look into getting a different phono stage.

 

[nopiano]

Given the size of the speakers, I’d be surprised if even subsonic output did enough damage to wreck one driver. I’d expect you would see it - obviously, with no grilles - and maybe hear some chuffing or buzzing, but not automatically enough to cause damage.

However, we weren’t there and it’s hard to know how loud you were playing, so I hope Focal give you a solution.

 

[CGMe]

If your floor is bouncy, your best option is probably a wall shelf, if that's a solid wall. If it's a stud wall then there probably isn't any benefit.

If you don't have floor bounce just go for an isolation platform. They are commercial available or you can make your own. Get a set of isolation feet and attach them to a board. Two best options for the board is big and heavy such as a butchers block chopping board, or dense and dead, such as the the thickest piece of MDF you can get your hands on.

The wall is indeed a solid wall. Was initially thinking on replacing my phono stage with one that has subsonic filtering, but the wall shelf would be an option. Would have to convince my girlfriend though I need to drill some holes in the wall. Still considering my options.

I don't blame you for that

I'm assuming you will be doing your own driver replacement and, with luck, only the lower of the two drivers in the right speaker will need replacing.

You know what you've heard, but to put your mind at rest, you could do a basic check of all 4.
With the power off, gently push each cone in and out.
It's essential to push with even pressure, ideally with fingers either side and around the junction of dustcap and cone.
There should be a very obvious scrapy feel to the faulty one - and hopefully all 3 others will be fine.

If you do the job and remove the scraper, then it can become the subject of a post mortem procedure.
(I used to examine scrapers in a service department. There's something that feels very wrong when cutting into a cone with a scalpel - especially on an expensive 18" bass driver - but scrapers are good for little else).
When you remove the voicecoil from the gap in the magnet, you'll soon confirm the cause of your scrape - and you'll see where your excess bass energy went.

Good luck in sorting things out.
I wouldn't bother with the expense of balanced phono stages.

Already had done that test this morning. Result is that it isn't the lower bass driver; it's actually the mid-bass driver that has the scraping sound. When listening to the speaker from really close with low volume it's actually also pretty easy to point out that it's the mid-bass driver. Fingers crossed that I can get my hands on a replacement driver. And I also have to figure out to remove that pretty ring that covers up the screws that hold the drive down without scratching the nice finish...

 

[CGMe]

Given the size of the speakers, I’d be surprised if even subsonic output did enough damage to wreck one driver. I’d expect you would see it - obviously, with no grilles - and maybe hear some chuffing or buzzing, but not automatically enough to cause damage.

However, we weren’t there and it’s hard to know how loud you were playing, so I hope Focal give you a solution.

Yeah, it's wrecked beyond a doubt. My previous post (which wasn't online yet when you replied) tells that I tested it. Nasty scraping sounds when softly pushing the mid-bass driver in. Some mechanical distortion when even playing at low volumes. I never use the grilles, prefer to see the cones on my speakers and there was indeed some nasty movement before.

 

[nopiano]

Yeah, it's wrecked beyond a doubt. My previous post (which wasn't online yet when you replied) tells that I tested it. Nasty scraping sounds when softly pushing the mid-bass driver in. Some mechanical distortion when even playing at low volumes. I never use the grilles, prefer to see the cones on my speakers and there was indeed some nasty movement before.

Well, I’m glad you diagnosed it anyway. Sorry it happened, but I was certainly familiar with this in the 1980s when I worked part-time in a hifi shop. It wasn’t that rare, but kit is generally much more rugged these days. However, your room looks spacious, and the sound probably gets swallowed up.

 

[Gray]

Fingers crossed that I can get my hands on a replacement driver.

You will be able to

Keep this thread updated on your progress
(preferably with repair / post mortem photos - we often do find that a picture really does speak a thousand words).

 

[gasolin]

acoustic feedback like in the old days when a mic where to close to the speakers ?

Do you have the old cartridge ?

Is a turntable your only source ?

If you played the song from a digital souce, would you have had the problem ?

 

[CGMe]

You will be able to

Keep this thread updated on your progress
(preferably with repair / post mortem photos - we often do find that a picture really does speak a thousand words).

I will keep this thread updated.

acoustic feedback like in the old days when a mic where to close to the speakers ?

Do you have the old cartridge ?

Is a turntable your only source ?

If you played the song from a digital souce, would you have had the problem ?

No audible feedback. Cone was flapping slowsly, so I thought it had to do something with sub-bass on the track in stead of it being harmful. The cartridge is 2 years old, with a stylus of 1 week. Currently I have the turntable, a CD-player and a Bluesound Node 2i as sources. Never noticed anything playing the same track from a different source, but that doesn't necessarily mean it hasn't been there before. I will investigate.

 

[twinkletoes]

The way you have that set up in the picture is fine, all very solid can't see infrasonic's getting through the cabinet especially if it’s full stuff. At least not enough to cause this sort of problem. Not to mention the speakers are already on spikes are pretty weighty as well. Not as if you have 15inch subwoofer sitting next to them.

Hate to say it but you have simply overdriven them. Used to see it all the time as a young lad listening at party levels (cd's) you would see the cone really moving on some bass heavy tracks and no sound. Blown a few speakers in my time along with subwoofers. boils down to crossovers letting to much band width through because manufactures are trying to hit the "full range" figures.

It doesn’t matter what the volume is, if you see that sort of movement in speakers pull back on the dial. Some amps give there max at quarter turn others at 11. It's why I don't like those sorts of digital read outs on 2 channel amps as it gives the illusion that you can run them at zero, Very few amps can do this. It could be the amp just lost control of the speakers as you push the amp into distortion.

I bet if you had a spl meter on your phone you were already getting peaks of a 100db.

Some speakers just can't handle volume despite there impressive stature. Come across a few in my time as well.

It's why buy sealed units with "limited" frequency range if I want more bass id buy a subwoofer.

 

[gasolin]

100db peaks is not a problem with that combination

Pa systems and my amp yamaha r-n600a can be limited and would be a good thing if you like to play loud

Not shure if having a nad amp with soft clipping would have help you

 

[CGMe]

The way you have that set up in the picture is fine, all very solid can't see infrasonic's getting through the cabinet especially if it’s full stuff. At least not enough to cause this sort of problem. Not to mention the speakers are already on spikes are pretty weighty as well. Not as if you have 15inch subwoofer sitting next to them.

Hate to say it but you have simply overdriven them. Used to see it all the time as a young lad listening at party levels (cd's) you would see the cone really moving on some bass heavy tracks and no sound. Blown a few speakers in my time along with subwoofers. boils down to crossovers letting to much band width through because manufactures are trying to hit the "full range" figures.

It doesn’t matter what the volume is, if you see that sort of movement in speakers pull back on the dial. Some amps give there max at quarter turn others at 11. It's why I don't like those sorts of digital read outs on 2 channel amps as it gives the illusion that you can run them at zero, Very few amps can do this. It could be the amp just lost control of the speakers as you push the amp into distortion.

I bet if you had a spl meter on your phone you were already getting peaks of a 100db.

Some speakers just can't handle volume despite there impressive stature. Come across a few in my time as well.

It's why buy sealed units with "limited" frequency range if I want more bass id buy a subwoofer.

Agreed with the digital dial not being representative for it's actual maximum output. The thing is though, that when the speaker started flapping it wasn't actually producing any (audible) bass. Still, I should have seen that as an indication to turn down the volume.

Just got a reply from the local distributor. They told me to contact a local dealer (which is actually a closeby hifi shop i visit quite often) to get it fixed. They also told me I should be able to order a separate driver to try and fix it myself if I wanted. Just sent the shop an e-mail, but don't expect a quick reply since their opening hours only include thursdays, fridays and saturdays. I'll you guys posted.

Really appreciate all the answers and information I'm getting so far.

 

[twinkletoes]

Agreed with the digital dial not being representative for it's actual maximum output. The thing is though, that when the speaker started flapping it wasn't actually producing any (audible) bass. Still, I should have seen that as an indication to turn down the volume.

Just got a reply from the local distributor. They told me to contact a local dealer (which is actually a closeby hifi shop i visit quite often) to get it fixed. They also told me I should be able to order a separate driver to try and fix it myself if I wanted. Just sent the shop an e-mail, but don't expect a quick reply since their opening hours only include thursdays, fridays and saturdays. I'll you guys posted.

Really appreciate all the answers and information I'm getting so far.

Thats the crossovers not protecting the speakers. or the amp loosing control. I highly dbout that is rumble you would see that quite early on with the volume.

Glad you're getting it sorted anyhow im sure you'll be back up and running in no time.