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Raidho C1.2 Issue with D250
#31
(20-May-2019, 18:38)martynbaker1 Wrote:
(20-May-2019, 13:45)Confused Wrote:
(19-May-2019, 12:13)martynbaker1 Wrote: Following further feedback here and on Audioshark regarding SAM impacting the higher frequencies, I followed this subject up again with Devialet. They told me for the first time SAM effects the ENTIRE FREQUENCY RANGE.

Can you clarify exactly what Devialet said?  The point being that SAM operates from 150Hz downwards, it does not work over the entire frequency range. 

From the Devialet white paper:

"SAM is effective on lower frequencies, up to 150Hz, yet its effects can be heard throughout the audio range"

So quite definitively, SAM operates below 150Hz.  Indeed, I have watched some 3 way speakers being SAM'ed at a Devialet event, only the bass driver was measured, so it cannot materially influence the tweeter. 

I suspect that Devialet were just reiterating the "yet its effects can be heard throughout the audio range" line, rather than implying that SAM itself operates above 150Hz?


Yes no problem here’s a specific point from their correspondence:

“SAM is design to feed every speaker with more energy and most of that energy goes to the bass drivers but some of that energy may go elsewhere. Depending on the filter, that may cause potential issues.

Therefore, please turn SAM off if the model does not match.”

This is new information to me and contrary to what I’ve been told before. It could also simply be covering their ass...


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Ummmm.....  Not the clearest of responses from a technical perspective.  Of course, one way to "feed every speaker with more energy" would be to turn the volume up a bit.  I think what they are trying to say is that SAM provides more current to the speakers, which the crossover may pass to the tweeter, but they do not actually say that, and the crossover should prevent the power going to the tweeter anyway.  Indeed, SAM is designed to limit the maximum current that goes to the bass driver to limit cone excursion and prevent overheating.  So in theory, you should be safer running SAM versus simply turning the volume up a bit.  Not worth worrying about too much now, although I suspect that you are absolute right re your very last sentence.....
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#32
So just over a week in and my tweeters are still working! System has been playing constantly at low volumes with the occasional blast at my usual listening levels.

Currently everything still sounds slow and still a bit flat. To be fair none of it has been used for almost 2 months! (my diy speakers using Audience drivers and PS audio Sprout have been getting a lot of love).

However, the imaging from the tweeters has never been better. It makes me wonder whether they needed some kind of service in any case. Raidho replaced the membrane in both tweeters to ensure they were matched and as good as new.

So still early days, though tweeters have lasted longer than before.

So I don’t think the issue has been robustly solved, and I think it’ll be a couple of weeks until I’m fully relaxed. However here are the options for the route cause:

1) Incorrect SAM profile effecting higher frequencies and causing ringing that fries the tweeter: as confused says, I’ve never heard of this before, though in the context of the correspondence with Devialet, they seem to be suggesting that SAM can have an effect on the higher frequencies, even if that’s not the intention of SAM.

2) Devialet repaired my amp without telling me: this actually seems plausible. It’s always been just the right hand channel that’s gone and not both tweeters. Repairing the amp without telling me would avoid taking responsibility (or am I being paranoid?)

Townshend repaired my speaker cables without telling me: this seems less likely as a repaired cable means a new loom of copper. Anyone with Isolda cables knows it’s impossible for those cables to look brand new once they’ve been moved around a couple of times.

For now I’m enjoying the music again. Almost forgot how much enjoyment I get out of a decent setup.

Thanks for everyone’s input.

Rock on all


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#33
(01-Jun-2019, 20:36)martynbaker1 Wrote: So just over a week in and my tweeters are still working! System has been playing constantly at low volumes with the occasional blast at my usual listening levels.

Currently everything still sounds slow and still a bit flat. To be fair none of it has been used for almost 2 months! (my diy speakers using Audience drivers and PS audio Sprout have been getting a lot of love).

However, the imaging from the tweeters has never been better. It makes me wonder whether they needed some kind of service in any case. Raidho replaced the membrane in both tweeters to ensure they were matched and as good as new.

So still early days, though tweeters have lasted longer than before.

So I don’t think the issue has been robustly solved, and I think it’ll be a couple of weeks until I’m fully relaxed. However here are the options for the route cause:

1) Incorrect SAM profile effecting higher frequencies and causing ringing that fries the tweeter: as confused says, I’ve never heard of this before, though in the context of the correspondence with Devialet, they seem to be suggesting that SAM can have an effect on the higher frequencies, even if that’s not the intention of SAM.

2) Devialet repaired my amp without telling me: this actually seems plausible. It’s always been just the right hand channel that’s gone and not both tweeters. Repairing the amp without telling me would avoid taking responsibility (or am I being paranoid?)

Townshend repaired my speaker cables without telling me: this seems less likely as a repaired cable means a new loom of copper. Anyone with Isolda cables knows it’s impossible for those cables to look brand new once they’ve been moved around a couple of times.

For now I’m enjoying the music again. Almost forgot how much enjoyment I get out of a decent setup.

Thanks for everyone’s input.

Rock on all


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One small interesting point, it appears SAM inverts the phase of your speakers for some reason. This was apparent because I use a subwoofer and needed to flip the phase 180 once SAM was switched off. Anyone know why this happens?


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#34
(01-Jun-2019, 22:00)martynbaker1 Wrote: One small interesting point, it appears SAM inverts the phase of your speakers for some reason. This was apparent because I use a subwoofer and needed to flip the phase 180 once SAM was switched off. Anyone know why this happens?


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One of the things SAM does is to correct phase errors in the bass region. Take a look at the phase and impedance plots in any speaker review in Stereophile and you will see quite large phase swings was a matter of course. I've seen a comment somewhere, can't remember where, saying that phase correction alone can add up to half an octave bass extension to a speaker.

SAM won't be "reversing the phase". What it does won't be as simple as a complete phase reversal. The phase will be changing by different amounts at different frequencies. Phase controls on subs that simply offer 0 and 180 degree options are pretty crude and the correct phase setting will almost certainly be somewhere in between those options but one of them will be closer to correct than the other. SAM is probably shifting phase in the area where the speaker is crossing over to the sub by just enough to make the opposite setting on the sub work better.
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Brisbane, Qld, Australia
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#35
(01-Jun-2019, 20:36)martynbaker1 Wrote:
So I don’t think the issue has been robustly solved, and I think it’ll be a couple of weeks until I’m fully relaxed. However here are the options for the route cause:

1) Incorrect SAM profile effecting higher frequencies and causing ringing that fries the tweeter: as confused says, I’ve never heard of this before, though in the context of the correspondence with Devialet, they seem to be suggesting that SAM can have an effect on the higher frequencies, even if that’s not the intention of SAM. …


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I don't use SAM, I hear a difference in the lower mids with SAM and most noticeably with some female voices which become a little heavier in tone. I don't think SAM is actually changing anything in the lower mids but I do think what it does in the bass changes the transition from bass to lower mids and we end up perceiving things a little differently in that area. I really can't see how SAM could make an actual change in the highs but I have also noticed at times that a change in the highs can affect how I perceive the bass and a change in the bass can affect how I hear the highs. We don't hear highs or lows in isolation, we hear them together in music and the combination creates a different perception than what we get when we listen to one without the other in my experience.
Roon Nucleus+, Devilalet Expert 140 Pro CI, Focal Sopra 2, PS Audio P12, Keces P8 LPS, Uptone Audio EtherREGEN with optical fibre link to my router, Shunyata Alpha NR and Sigma NR power cables, Shunyata Sigma ethernet cables, Shunyata Alpha V2 speaker cables, Grand Prix Audio Monaco rack, RealTRAPS acoustic treatment.

Brisbane, Qld, Australia
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#36
(01-Jun-2019, 22:52)David A Wrote:
(01-Jun-2019, 22:00)martynbaker1 Wrote: One small interesting point, it appears SAM inverts the phase of your speakers for some reason. This was apparent because I use a subwoofer and needed to flip the phase 180 once SAM was switched off. Anyone know why this happens?


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One of the things SAM does is to correct phase errors in the bass region. Take a look at the phase and impedance plots in any speaker review in Stereophile and you will see quite large phase swings was a matter of course. I've seen a comment somewhere, can't remember where, saying that phase correction alone can add up to half an octave bass extension to a speaker.

SAM won't be "reversing the phase". What it does won't be as simple as a complete phase reversal. The phase will be changing by different amounts at different frequencies. Phase controls on subs that simply offer 0 and 180 degree options are pretty crude and the correct phase setting will almost certainly be somewhere in between those options but one of them will be closer to correct than the other. SAM is probably shifting phase in the area where the speaker is crossing over to the sub by just enough to make the opposite setting on the sub work better.


That’s interesting. Yes the REL G2 only has 180, hence I actually delay the speakers in the Dev configuration to get the timing right. Perhaps me finding things a bit slow might be the lack of SAM or the slight phase difference with the sub now SAM is off. Interesting... some more exploring when I have more time...


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#37
(01-Jun-2019, 22:57)David A Wrote:
(01-Jun-2019, 20:36)martynbaker1 Wrote:
So I don’t think the issue has been robustly solved, and I think it’ll be a couple of weeks until I’m fully relaxed. However here are the options for the route cause:

1) Incorrect SAM profile effecting higher frequencies and causing ringing that fries the tweeter: as confused says, I’ve never heard of this before, though in the context of the correspondence with Devialet, they seem to be suggesting that SAM can have an effect on the higher frequencies, even if that’s not the intention of SAM. …


Sent from my iPhone using Tapatalk

I don't use SAM, I hear a difference in the lower mids with SAM and most noticeably with some female voices which become a little heavier in tone. I don't think SAM is actually changing anything in the lower mids but I do think what it does in the bass changes the transition from bass to lower mids and we end up perceiving things a little differently in that area. I really can't see how SAM could make an actual change in the highs but I have also noticed at times that a change in the highs can affect how I perceive the bass and a change in the bass can affect how I hear the highs. We don't hear highs or lows in isolation, we hear them together in music and the combination creates a different perception than what we get when we listen to one without the other in my experience.


Yes this is so true. Biggest difference I noticed in mids was when adding a sub operating below 30hz.

So I can’t perceive any changes in the highs with SAM on - this is just what Dev support mentioned. I’m going to follow up with them for clarification I think.


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#38
(02-Jun-2019, 06:58)martynbaker1 Wrote:
(01-Jun-2019, 22:57)David A Wrote:
(01-Jun-2019, 20:36)martynbaker1 Wrote:
So I don’t think the issue has been robustly solved, and I think it’ll be a couple of weeks until I’m fully relaxed. However here are the options for the route cause:

1) Incorrect SAM profile effecting higher frequencies and causing ringing that fries the tweeter: as confused says, I’ve never heard of this before, though in the context of the correspondence with Devialet, they seem to be suggesting that SAM can have an effect on the higher frequencies, even if that’s not the intention of SAM. …


Sent from my iPhone using Tapatalk

I don't use SAM, I hear a difference in the lower mids with SAM and most noticeably with some female voices which become a little heavier in tone. I don't think SAM is actually changing anything in the lower mids but I do think what it does in the bass changes the transition from bass to lower mids and we end up perceiving things a little differently in that area. I really can't see how SAM could make an actual change in the highs but I have also noticed at times that a change in the highs can affect how I perceive the bass and a change in the bass can affect how I hear the highs. We don't hear highs or lows in isolation, we hear them together in music and the combination creates a different perception than what we get when we listen to one without the other in my experience.


Yes this is so true. Biggest difference I noticed in mids was when adding a sub operating below 30hz.

So I can’t perceive any changes in the highs with SAM on - this is just what Dev support mentioned. I’m going to follow up with them for clarification I think.


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Just don't use SAM on current firmware version (Firmware 13.1.3 + DOS 2.2.4)! This could endanger your speakers. Please see my previous post here (#19).
Just wait for next firmware version...
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#39
(02-Jun-2019, 10:17)daniel.avasilichioaei Wrote:
(02-Jun-2019, 06:58)martynbaker1 Wrote:
(01-Jun-2019, 22:57)David A Wrote: I don't use SAM, I hear a difference in the lower mids with SAM and most noticeably with some female voices which become a little heavier in tone. I don't think SAM is actually changing anything in the lower mids but I do think what it does in the bass changes the transition from bass to lower mids and we end up perceiving things a little differently in that area. I really can't see how SAM could make an actual change in the highs but I have also noticed at times that a change in the highs can affect how I perceive the bass and a change in the bass can affect how I hear the highs. We don't hear highs or lows in isolation, we hear them together in music and the combination creates a different perception than what we get when we listen to one without the other in my experience.


Yes this is so true. Biggest difference I noticed in mids was when adding a sub operating below 30hz.

So I can’t perceive any changes in the highs with SAM on - this is just what Dev support mentioned. I’m going to follow up with them for clarification I think.


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Just don't use SAM on current firmware version (Firmware 13.1.3 + DOS 2.2.4)! This could endanger your speakers. Please see my previous post here (#19).
Just wait for next firmware version...


I’m not on pro so am using the 10. Firmware. Keen to hear more once you get further feedback from Devialet.


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