Weird/ confused!!!

[lonergan2468]

I really dont know where to start.

Using my Audiolab CD player through my Emile KI40L..it starts to distort...both channels.....OK the amp has had recent service..and this is related to previous problems.....so clean bill of health. OK removed CD player used my sons Rega..no problems...OK..tried CD player, again started to distort awfully....Creative audio advised me to do the factory restore setting...turn power off, hold for/back, then power on..etc..etc..ok..then played CD..after 20 mi .started to distort...

Here is the interesting bit..removed Emile...placed Icon audio amp..AUdiolab works fine..

Also when distortion happens, checked all biasing...all ok....

I just dont get it..The emile is not human..it is a machine..it should just accept the signal that is going through it....The whole thing is becoming confusing...is it the amp..is it the CD player....

I hope that there is some kind person who can help me out...

[walpurgis]

Sounds like input overload Tim, which is strange if you didn't get it before.

[lonergan2468]

ok, the rega CD works fine..perhaps the Audiolab is over loading ????????

[walpurgis]

Did you use the Audiolab player with the Emile before?

[southall-1998]

His Audiolab CD Player is something like 2.5V output.

S.

[Audio Advent]

I must admit I was confused reading the post! Stream of conciousness almost, missing a little context... Where does the human bit come in??!

If I understood correctly - that the Emile integrated amp distorts when playing a CD through it and both CD players are fine as shown by using a different amp, but that the distortion only comes in on the Emile amp after some time - then it just sounds like distortion caused by something that is effected by the operating temperature of the amp, e.g. a dry solder joint or a failing leg joint on a component like a capacitor or resistor.

That the disortion is on both channels at once, I'd suspect it to do with the power supply or anything common to both channels.

I am no technical expert though and am doing nothing than applying logic to a tiny amount of knowledge of electronics and hifi....

[Audio Advent]

OK removed CD player used my sons Rega..no problems...OK..tried CD player, again started to distort awfully....

Aren't you saying here that the Rega distorted on a second try out of it?

When you say "started to distort" does that mean after a while or instantly and how long after the Emile has been turned on/warmed up? "Started to distort" implies to me that it at first didn't distort and then gradually began too, perhaps getting worse as time went on..

[Spectral Morn]

Definitely sounds like an input overload. An attenuator would solve it but this isn't an ideal solution. Done a check and its 2.8 which is quiet a bit over what the industry standard should be which is 2.


Regards Neil

[Audio Advent]

What happens if you have both the Audiolab and the Rega both plugged in on different inputs at the same time and switch between the two?

How about the left channel of the Audiolab plugged in to the left channel of your usual CD input and the right channel of the Rega in the right channel of your usual CD input? If it's definately about the Audiolab then left channel will be distorted whilst the right will be fine.. Hopefully the emile has a balance control to make things easier to test.

EDIT: I see it has dual volume controls so is very easy to test!

[Firebottle]

If your Audiolab works fine though your Icon then it sounds like the Emille is at fault, recent service or no.

I think the input to the Emille runs directly to the volume control, so you shouldn't have an overload problem with the control adjusted for normal listening level.

:cool: Alan

[lonergan2468]

The Rega cd player works fine with the Emile......

Using another amp..Icon audio....the audiolab, and rega are fine....

The Emille only goes bizarre when using the audiolab

[Audio Advent]

Definitely sounds like an input overload. An attenuator would solve it but this isn't an ideal solution. Done a check and its 2.8 which is quiet a bit over what the industry standard should be which is 2.


Regards Neil

Not definately if the distortion only comes about after some time. He might have only tested with the Rega when the amp was cold..

[lonergan2468]

hmmmmmmm

[Audio Advent]

hmmmmmmm

:D Hmmm indeed!

Did the Audiolab work with the Emile before and is the distortion instant, both when the amp is cold and when it's been on for a while?

It's possible there is some kind of earthing arrangement with the Audiolab and associated cables which could cause distortion given some particular design of the Emile amp.... don't know what that might be, but I reckon it would be possible!

[struth]

If its working fine with the other amp then its pretty much gonna be to much input for the amp in question. pity it doesn't have variable outputs


edit. if you can lay hands on a passive pre then you could use that to attenuate... better than just attenuators and more accurate.

[southall-1998]

My Rega Planet CD Player works and plays fine with Dad's (lonergan2468) Emile amp at all times.

The Audiolab CD Player is causing the rough/distortion sounds through the Emile.

SIMPLES!!!

S.

[Audio Advent]

Creative audio advised me to do the factory restore setting...turn power off, hold for/back, then power on..etc..etc..ok..then played CD..after 20 mi .started to distort...

Here is the interesting bit..removed Emile...placed Icon audio amp..AUdiolab works fine..


Not that simples! Because as stated in the quote above, the Audiolab also worked fine with the Emile amp! And it took a whole 20 minutes for the distortion to kick in.

What is time-based that can cause distortion? I can only think of something temperature based or something oddly software based (sounds like the Audiolab has software inside which can be reset, probably to do with receiver chips, memory buffers, modern dacs etc..).

When you tested the Audiolab with the Icon audio amp, how long did it take to swap them over, how long did you test it for? More than 20 minutes? Fault could be a temp related thing in the Audiolab but which didn't show itself with the Icon Audio amp because it was only tested quickly as anyone would, a quick test.

EDIT: in other words, no only does everthing need to be tested in different combinations to sort out where the distortion is coming from, but also at different temperatures for those different combinations.

[Reffc]

I have had the very same amp for some while now and never had one single issue, nothing at all. I have stripped and examined the amp and circuit and it's pretty bomb proof to be honest and of very high quality, especially the transformers, where it matters. I have also played many different CDPs through it without a single issue. The CDP input will be configured (in this case) for a standard 2v CD input sensitivity and it's speculative at this case to assume that it is an overload but it is possible. I would suggest that you ask the guys who repaired the amp and know the circuit as they are the experts. I can only speak from the experience I've had but the Emille Ki-40L remains as one of the highest quality valve amps I've so far ever come across, so stick with it. It's probably something simple/overlooked, but asking Radford's who've had yours apart, I would suggest, is the best place to start!

[anthonyTD]

Maybe there is DC offset coming out of the outputs of the player in question ? if the amp that has an issue with it has no capacitors in the front end to block this, then it could be upsetting the bias on the first gain stage of the amp, causing it to distort.
Just a thought.
A...

[Reffc]

Inside shot of amp Anthony if of any use for clues:

http://highfidelity.pl/foto_testy/1011/emille/03.jpg

http://highfidelity.pl/foto_testy/1011/emille/13.jpg

http://highfidelity.pl/foto_testy/1011/emille/14.jpg

[lonergan2468]

Yes..The op of the audiolab is 2.5..I have 2 attenuators..will try that. I love the detailed sound of the Emille......

[anthonyTD]

Thanks paul,
Yes, if you follow the signal path [shown on last pick] you will see that there is just a grid resistor to ground[normal] and nothing else in the signal path to pin two on the valve base, which is the grid of the first gain stage!
Hope this helps.
A...

[Reffc]

Thanks paul,
Yes, if you follow the signal path [shown on last pick] you will see that there is just a grid resistor to ground[normal] and nothing else in the signal path to pin two on the valve base, which is the grid of the first gain stage!
Hope this helps.
A...

Thanks Anthony, so a simple fix would be to add a DC blocking cap at the input and connect the input to one leg of the cap and the other leg to the signal input track on the PCB? What value would you recommend (presumably a poly bipolar axial cap, 400V rated?)

[anthonyTD]

Yes,
Just lift the white wire out of the printed circuit board, and put the cap between the white wire, and the board connection.
Try a 100nf, [doesent have to be a high voltage one, something at least 25v working] that should be fine for starters.
A...
Thanks Anthony, so a simple fix would be to add a DC blocking cap at the input and connect the input to one leg of the cap and the other leg to the signal input track on the PCB? What value would you recommend (presumably a poly bipolar axial cap, 400V rated?)

[Reffc]

Yes,
Just lift the white wire out of the printed circuit board, and put the cap between the white wire, and the board connection.
Try a 100nf, [doesent have to be a high voltage one, something at least 25v working] that should be fine for starters.
A...

Thanks Anthony, very helpful. I'm sure that Tim could try this mod or have someone do it for him locally and (hopefully) job done. RE rating, yes of course, it's not on the Hv side of the circuit. Cost = a few pounds ;) Well spotted. Presumably a similar cap on the output stage of the CDP would work equally as well?

[anthonyTD]

No worries,
Some source equipment, like CD players etc have directly coupled output stages, ie; they have no cap on the output to block and isolate the output, so if there is any significant level of DC offset coming out of the player's output, they can upset the front end of amplifiers with no input capacitors fitted.
Hope it fixes the issue.:)
A.
Thanks Anthony, very helpful. I'm sure that Tim could try this mod or have someone do it for him locally and (hopefully) job done. RE rating, yes of course, it's not on the Hv side of the circuit. Cost = a few pounds ;) Well spotted. Presumably a similar cap on the output stage of the CDP would work equally as well?

[Firebottle]

You would need a larger capacitor value, so more expense, at the CDP output as you would be driving into the impedance of the volume control on the Emille.

The impedance of the first grid is a lot higher so 100nF is OK there,


Good shout Anthony about possible DC offset :)

:cool: Alan

[anthonyTD]

:)
You would need a larger capacitor value, so more expense, at the CDP output as you would be driving into the impedance of the volume control on the Emille.

The impedance of the first grid is a lot higher so 100nF is OK there,


Good shout Anthony about possible DC offset :)

:cool: Alan

[Audio Advent]

But the thing that people are forgetting is that the Audiolab worked absolutely fine with the Emile amp for a whole 20 minutes before starting to distort..

That would suggest the Audiolab was at fault (e.g. a sudden DC offset caused by a dry joint which kicks in after 20 minutes warm-up) and adding a cap on it's output (if it doesn't have one) wouldn't fix the fault it would only be a work around.

Need to check if it is indeed the Audiolab and to see if the fault always kicks in after 20 minutes from cold consistantly.

[Firebottle]

A very quick check of the Audiolab with a voltmeter on the output (when the fault is showing) will confirm or discount the Audiolab at fault.

[anthonyTD]

Exactly Alan!
For others who have concerns at least about my reasoning, i will explain:
The whole reason for my explanation was based on the understanding that the player in question had been examined and found to be working as it was designed to.
Sometimes certain designs are just not compatible with other equipment designs, my explanation, and work around was based on that.
A very quick check of the Audiolab with a voltmeter on the output (when the fault is showing) will confirm or discount the Audiolab at fault.

[DSJR]

You beat me to it Anthony :respect:

I read the first few posts and 'DC offset' immediately came to mind. Not trying to be a smart arse here, but I'm reminded of a recent conversation with hifi Dave, who tried a CD player straight into his Crown DC300A (no DC blocking as on lower models of this range) and got the most godawful noises coming through, something the amp didn't do at all when we last used it in a lengthy session loudly into Harbeth 40.1's.

I have no idea what value of blocking cap may need to be used if this is the problem (My Crown D-60's use 25uF bipolar caps and the Digit Opto uses 100uF 16V non bipolar), as I think the exact value would be impedance related? Hopefully, someone properly qualified will come along to help ;)

In the meantime Tim, you could always get shot of the Audiolab and get a proper player like a Rega Apollo R (runs for cover :lol:)

[anthonyTD]

:)
You beat me to it Anthony :respect:

I read the first few posts and 'DC offset' immediately came to mind. Not trying to be a smart arse here, but I'm reminded of a recent conversation with hifi Dave, who tried a CD player straight into his Crown DC300A (no DC blocking as on lower models of this range) and got the most godawful noises coming through, something the amp didn't do at all when we last used it in a lengthy session loudly into Harbeth 40.1's.

I have no idea what value of blocking cap may need to be used if this is the problem (My Crown D-60's use 25uF bipolar caps and the Digit Opto uses 100uF 16V non bipolar), as I think the exact value would be impedance related? Hopefully, someone properly qualified will come along to help ;)

In the meantime Tim, you could always get shot of the Audiolab and get a proper player like a Rega Apollo R (runs for cover :lol:)

[southall-1998]

You beat me to it Anthony :respect:

I read the first few posts and 'DC offset' immediately came to mind. Not trying to be a smart arse here, but I'm reminded of a recent conversation with hifi Dave, who tried a CD player straight into his Crown DC300A (no DC blocking as on lower models of this range) and got the most godawful noises coming through, something the amp didn't do at all when we last used it in a lengthy session loudly into Harbeth 40.1's.

I have no idea what value of blocking cap may need to be used if this is the problem (My Crown D-60's use 25uF bipolar caps and the Digit Opto uses 100uF 16V non bipolar), as I think the exact value would be impedance related? Hopefully, someone properly qualified will come along to help ;)

In the meantime Tim, you could always get shot of the Audiolab and get a proper player like a Rega Apollo R (runs for cover :lol:)


What is the Apollo R's output voltage, Dave?

S.

[Audio Advent]

I've just been PM'd by Southall-1998 to stay out of this thread and to "Grow Up" - What the hell is that all about??! NUTS!


Anyway, from what's been said on this thread, I'm not sure the Audiolab CD player has necessarily been determined to be working fine other than it worked ok with the ICON amp at one point. Needs to at least get a voltmeter on it's output as firebottle says, check for DC.

Still, the 20 minutes where the Audiolab worked fine into the Emile before distorting I think is the clue to the problem. Yes might be DC offset, but might be DC offset which is due to a new fault in the Audiolab, not to it's normal operation (otherwise surely it will have always been distorting, not just recently).

Adding DC blocking caps to the amp would help that but the Emile would have deliberately designed it without, most likely for sonic and/or impedance reasons. Therefore you might end up changing the sound of the amp. Better to sort out a DC problem at it's source..

[Marco]

I've just been PM'd by Southall-1998 to stay out of this thread and to "Grow Up" - What the hell is that all about??! NUTS!


Indeed, and trust me, he's been appropriately reprimanded. Please accept my apologies for Shane's outrageous and unacceptable behaviour. It will not happen again.

Marco.

[anthonyTD]

No one on this forum should feel intimidated, or afraid to post they’re ideas, That’s one of the key elements that differentiates AOS from other forums, All views and ideas are welcome, Sam does indeed make a valid point, the only piece of equipment that seems to upset the amp in question is the Audiolab, which should indeed have been examined thoroughly to make sure it is working properly before any modifications are made permanently to the amplifier, my advice was given as an explanation as to what could be going on, if DC offset was indeed suspected as the cause of the distortion, then the player should have first and foremost been examined again to see if a measurement of potentially problematic DC voltage was present at the outputs of the Audiolab player, if the measurement was considerably above what would be deemed as normal according to the manufacturers original specifications, then it goes without saying, that the first port of call is to repair the player.
If’ on the other hand, the DC output measured at the players output is deemed normal, it could still be enough to upset directly coupled inputs of a valve amp, which was the whole reason I suggested the work around with the caps. I really hope this clarifies things.:)

I've just been PM'd by Southall-1998 to stay out of this thread and to "Grow Up" - What the hell is that all about??! NUTS!


Anyway, from what's been said on this thread, I'm not sure the Audiolab CD player has necessarily been determined to be working fine other than it worked ok with the ICON amp at one point. Needs to at least get a voltmeter on it's output as firebottle says, check for DC.

Still, the 20 minutes where the Audiolab worked fine into the Emile before distorting I think is the clue to the problem. Yes might be DC offset, but might be DC offset which is due to a new fault in the Audiolab, not to it's normal operation (otherwise surely it will have always been distorting, not just recently).

Adding DC blocking caps to the amp would help that but the Emile would have deliberately designed it without, most likely for sonic and/or impedance reasons. Therefore you might end up changing the sound of the amp. Better to sort out a DC problem at it's source..

[The Black Adder]

That is truly awful. That's a first for me here... blimey!

Do you think it would be good to ask Sam for the PM so we can see, maybe?

[Marco]

Hi Jo,

No, I think that should remain private between Shane and Sam. The important thing is, as Anthony has outlined, no-one should be made to feel intimidated. That is *completely unacceptable*, and anyone here guilty of that behaviour will be severely dealt with!

Marco.

[The Black Adder]

Righto.

I just don't know what kind of mindset someone has to be in to PM something like that, it's just a bit freaky!

[Marco]

Indeed, but best leave it there :)

Marco.

[The Black Adder]

OK.

[lonergan2468]

Many thanks to everyone for assisting,and your suggestions, OK, we used attenuators on the Audio lab CD player..and this has worked..last night I played for a few hours.....

I really like the sound of the Emile.....and of course the Audiolab CD player....

[walpurgis]

Glad to hear it was a simple fix Tim. So it was input overload then. Seemed the first thing to check to me.

[anthonyTD]

Indeed,
Still doesent explain why it was fine for a while, surely if it was an input overload problem, it would have distorted from the start. the attenuation could still be masking an underline issue with the player.
Glad to hear it was a simple fix Tim. So it was input overload then. Seemed the first thing to check to me.

[lonergan2468]

I dont know....perhaps the amp has to warm up...first...

Yep, and I think that this must have been a problem...that has been around for a while....A while back there was aproblem with biasing..that was sorted, and recently when it started to misbehave, distorted sound, purple flashing...I sent it to Radford revival..who did some modifications inc the protection fuses....so when this recent problem occurred...Radford said to check the biasing..we did..was all ok....leading one to question input....and WOW..u cracked it..the 2.5 in...from the AUdiolab, The Icon amp is fine with that.....

I did have a message from another Emile owner stating that my post is not really suitable, in that I have posted negative comments that could affect "resale value"..I merely asked for support to determine a problem....and as suggested ..we have narrowed it down to the overload input....the fact that I have asked for support is only testament to my actual liking of the Emile amp...in fact I love this amp....

[Firebottle]

I'm not convinced it's overload either. As far as I can tell from the photos posted the input to the Emille goes through some selector relays then straight to the volume control.

If the volume control is working properly then overload is impossible as turning the volume right down increases the attenuation massively.
My guess is that there is possibly a small leakage (DC present) from the Audiolab output, then fitting the attenuators lowers the resistance of the circuit leading to a lower DC offset, insufficient to upset the input of the Emille.

The only way to prove this is to beg borrow or steal a digital voltmeter and measure the Audiolab output with and without the attenuator connected.

If you weren't such a long way away in Torquay I, or I'm sure Anthony, would do the quick test and we'd all know exactly what was happening :)

[lonergan2468]

LOL, I just phoned The retail supplier of the Audiolab to explain as they advised me to do do the factory reset, which of course did not sole the problem, he states that the Emile cannot take the high op of the CD...OK, why is there a CD input ???..and that the op voltage is 2......Anyway..rather than using the attenuators..long term....it might be a good idea to get radford to do something with the input section...as suggested within the forum.....LOL..at least I was able to enjoy my combination last night....

[Macca]

CD players can have outputs from as low as 1.0v up to 3.0v

Standard is 2.0v

So it won't be an issue with most players. But if overloading it should be obvious from the outset, not kick in after a while.

[Reffc]

Well, I for one am not convinced it's any amp issue. As already mentioned, I have used various CDPs with my Ki-40 and never had any overload issues with it. The CD input is designed to take 2vRMS and I have used players with 2.5V RMS with no overload issues at all. Without the CDP being properly tested, this all still seems to be speculation as from what has previously been said, it would seem to point more towards a DC offset problem with the CDP. I currently use an Apollo R by the way which outputs 2.15V RMS and zero issues with that.

[southall-1998]

Well, I for one am not convinced it's any amp issue. As already mentioned, I have used various CDPs with my Ki-40 and never had any overload issues with it. The CD input is designed to take 2vRMS and I have used players with 2.5V RMS with no overload issues at all. Without the CDP being properly tested, this all still seems to be speculation as from what has previously been said, it would seem to point more towards a DC offset problem with the CDP. I currently use an Apollo R by the way which outputs 2.15V RMS and zero issues with that.

Good for you, Paul.

S.

[DSJR]

+1 for a possible DC offset on the player (nothing wrong with the amp if it doesn't like this, but why buy such unknown stuff that will be extremely difficult to resell in the hard-up UK used market, whatever the value?). Glad the attenuators sorted it, at least for now, as if there is DC, it'll be attenuated too as said above.

[Reffc]

Good for you, Paul.

S.

????

Shane, all I and many others are trying to do on this thread is to genuinely offer help and to help sort out seemingly ongoing problems. It seems that the DC offset is still a very valid (and probably the most likely) cause so it is genuinely baffling to have this rejected as Anthony and Alan especially are probably the best qualified on this thread to comment and have raised the DC issue as being a very likely cause. I happen to agree simply because I have never experienced any "overload distortion" with any player up to 2.5V output on an identical amp. As for the CDP manufacturer's comment that the amp want designed for a 2v output, that's plainly not correct at all and as several people have stated already, unless the cdp output is tested how do you know there isn't a problem? It just seems like common sense is being ignored here in favour of lip service. Many valve amps don't have decoupling caps on the inputs, especially older ones, not just this one by the way so that's not at all uncommon. However, as Anthony has offered, to install them is a relatively easy thing to do IF desired.

[southall-1998]

????

Shane, all I and many others are trying to do on this thread is to genuinely offer help and to help sort out seemingly ongoing problems. It seems that the DC offset is still a very valid (and probably the most likely) cause so it is genuinely baffling to have this rejected as Anthony and Alan especially are probably the best qualified on this thread to comment and have raised the DC issue as being a very likely cause. I happen to agree simply because I have never experienced any "overload distortion" with any player up to 2.5V output on an identical amp. As for the CDP manufacturer's comment that the amp want designed for a 2v output, that's plainly not correct at all and as several people have stated already, unless the cdp output is tested how do you know there isn't a problem? It just seems like common sense is being ignored here in favour of lip service.

Don't take me too seriously, Paul.

S.

[DSJR]

Paul, I think he means it's good that you're using a Rega CD player right now..... :)

[Reffc]

Paul, I think he means it's good that you're using a Rega CD player right now..... :)

Ahh...yes, the Rega's a nice player ;)

[lonergan2468]

Spoke to radcliff to day. They want me to send the emile and the Audiolab to them...so will do that...

[lonergan2468]

UNKNOWN !!!!...The audiolab CD8200 has a cult following, and excellent reviews. The Emille amp...RRP approx 6000..pounds, has fine components..and is relatively well known in the UK, and excellent reviews !

[lonergan2468]

Radford sent me some pics of the inside, and their protection fuses...

http://i1278.photobucket.com/albums/y519/Tadgh_Lonergan/radford_zpsz5s5wbol.jpg (http://s1278.photobucket.com/user/Tadgh_Lonergan/media/radford_zpsz5s5wbol.jpg.html)

http://i1278.photobucket.com/albums/y519/Tadgh_Lonergan/radford2_zpsacxjwg8k.jpg (http://s1278.photobucket.com/user/Tadgh_Lonergan/media/radford2_zpsacxjwg8k.jpg.html)

Top left and far right, note the new fuses....

[The Black Adder]

that is one very neatly set out amp...! :)

[Radford Revival]

A note about the HT fuses, they were a precautionary measure and the modification was done in such a way that it was completely reversible.

[lonergan2468]

It was a good idea.....

[lonergan2468]

This amp has some nice stuff inside..so I have been told....

[anthonyTD]

Very nicely done!
HT fuses in my view' are a must on any valve amp.
A...
Radford sent me some pics of the inside, and their protection fuses...

http://i1278.photobucket.com/albums/y519/Tadgh_Lonergan/radford_zpsz5s5wbol.jpg (http://s1278.photobucket.com/user/Tadgh_Lonergan/media/radford_zpsz5s5wbol.jpg.html)

http://i1278.photobucket.com/albums/y519/Tadgh_Lonergan/radford2_zpsacxjwg8k.jpg (http://s1278.photobucket.com/user/Tadgh_Lonergan/media/radford2_zpsacxjwg8k.jpg.html)

Top left and far right, note the new fuses....