PMC Twenty 21, listening fatigue?

Hal posted:

Richieroo posted:

Hi am I right in taking that the twenty 5 series is brighter than the old twenty series....... if so omg ..... my little 20.21's are just about right ... meaning they are still exciting at the top end ... grills on.

I have not yet heard new 25.21 or 25.22 but if new series is  hotter at top end this will give me something to consider. My 20.21's are already quite revealing. I have been thinking about getting 25.21 or 22 to go with CD5si-XS2-HcDR.

They are not overly bright. Listen and you will understand. It is clear that they are not to everyone's taste, but I don't think anyone said they are bright. The grilles do make them "smoother". And what they do they do well. I've find they do most things better than the Twenty series and what they lost in ethereal laser pinpoint staging they gained tenfold in solidity of presence. They happen to sound better with the grilles on in my room (I have 2x7m of continuous glass window to contend with) and the OP may find he prefers the 20.21s that way too. I try to be brutal and honest about the things I own. I've also been pretty forthright about how amazing I find these speakers and dedicated a whole thread to comparing to the Twenty range I uprgaded from. They wowed me and continue to wow me in a way I have not been wowed since I heard triamped Aktiv Kabers for the first time in the 90s.

I don't think the grilles are simply an afterthought at PMC either. The Twenty5 grilles are also redisigned and are a much denser, heavier affair. While they look better naked, the grilles were not designed as a thow away add-on.

Assuming that the OP is not simply finding that the PMCs in general are not their cup of tea (which is possible), I would say that there are a number of issues to look at as identified in this thread. Stands, grilles, placement, and I have to, the CD5si. The Twenty series can be a lot more revealing of the system than you would expect for their price. And while the Twenty range was fairly forgiving, the Twenty5 series take no prisoners and lay the system bare. I don't think 25.21 will take a liking to a CD5si - but I could be wrong.

feeling_zen posted:

And while the Twenty range was fairly forgiving, the Twenty5 series take no prisoners and lay the system bare. I don't think 25.21 will take a liking to a CD5si - but I could be wrong.

I very much agree with Feeling_Zen. As I wrote in a different thread, I feel the 25.23 don't tolerate very well poorly recorded music -- and, as Felling_Zen suggests, weak links in the chain get exposed. My earlier Neat SX1 were much more forgiving. Well, I guess there is a price for the transparency and the excitement the Twenty5 series offers... 

PMC tweeters sound good until you compare them to really excellent tweeters, then they start to sound course and grainy by comparison.

That's been my experience anyway.

badlands posted:

PMC tweeters sound good until you compare them to really excellent tweeters, then they start to sound course and grainy by comparison.

That's been my experience anyway.

In your view, what's the step up from PMC?

Focal, B&W, and Dynaudio tweeters all sound more refined to my ears at least.

I had the twenty.23 for a few years and they are very accomplished imho. The slight 'grain' was apparent on some recordings more than others and I always put it down to the crossover point.

When I moved to S400 the scale and openness of the larger, more sophisticated speaker, was immediately obvious.

G

Mike-B posted:

feeling_zen posted:

Metal dome? They use a fabric dome tweeter. The protective mesh is indeed metal.

Whoops ..  ..  I just checked the spec's & yes I was mistaken.     I 'noticed' the treble & as the tweeter looks remarkably similar to the metal dome Elac drivers I had back in the 80's ,    I just assumed - my bad ...........  it does not change my opinion that the treble was not quite to my taste.   I'm now toying with 282 & active ATC's,  they sound as I like it,  but maybe a house move first  

ooohhhh Mike - which active ATCs are you listening too.... i am so tempted to go that way and get my 252DR directly feeding some actives

Timo posted:

feeling_zen posted:

And while the Twenty range was fairly forgiving, the Twenty5 series take no prisoners and lay the system bare. I don't think 25.21 will take a liking to a CD5si - but I could be wrong.

I very much agree with Feeling_Zen. As I wrote in a different thread, I feel the 25.23 don't tolerate very well poorly recorded music -- and, as Felling_Zen suggests, weak links in the chain get exposed. My earlier Neat SX1 were much more forgiving. Well, I guess there is a price for the transparency and the excitement the Twenty5 series offers... 

hmm - but I didn't find the twenty5 series that transparent - the treble graininess (to my ears) held back definition and and subtlety - almost like it was quantizing the sound.... it was cathedral choir music that was shockingly poor - but play back recordings through different or possibly more capable tweeters and it all came alive and became credible when you shut your eyes .... i listened on Statement system and my more humble home 252DR system - and the effect was identical... perhaps it is only noticeable to certain people???

Simon

Hi Simon,  I've only listened to 19A's so far.  I really liked the sense of presence & clarity in mid & treble, but not so hot on bass, they had a lot of impact & real feel of bass but I was not convinced with sub 40Hz & fundamentals.  I liked the tangible 3D soundstage, space, air & atmosphere, & that with the mid/treble detail I could live with the sub-bass.  I was looking forward to 40A's,  but sensible hat on ...... I will be downsizing house in a year or two as 5 beds for 2 peeps (etc)  ....  so listening room first, speaker choice after that.

badlands posted:

PMC tweeters sound good until you compare them to really excellent tweeters, then they start to sound course and grainy by comparison.

That's been my experience anyway.

To put this in context, which specific PMCs have you heard? As with many brands, the tweeters PMC use have changed them over time, and indeed they use different ones on the different ranges: there are two different ones used across their present top SE range, which are different from Fact, which are different from 25, which are different from 20, etc. presumably improving as you go from one range to the next.

Innocent Bystander posted:

Excuse my ignorance of Linn Exakt and please correct me if I have got this wrong.

I assume that the process of designing filters is in-room using a microphone at the listening position? If so, then what you are reporting is the behaviour of the speakers and the room, as affected by the placement of the speakers and listening position and everything in the room, or some averaging thereof. That then would mean that the filters and assessment of what they are doing is not a good indication of the situation in any significantly different setup?

Alternatively the measurements under some standardised conditions, whether anechoic, or nominal room and positioning - in which case in fact the same applies if the listening setup is significantly different.

Either way this does not seem to help the OP, unless what is significant is the observation that the 15dB cut of the tweeter (full range of it?) relative to mid-bass is unusual, suggesting that relative to the midbass the treble is brighter than commonly found with speakers, possibly contributing to fatigue?

As an aside, how do the speakers sound with the filtration applied? I once tried Dirac Live, which uses measurements atveraged from a number of locations just around the listening position, at a time when my room layout was wrong and causing significant peaks and troughs at the listening position - and the result just killed the music, and it was better with all the original imperfections, obvious though they were. (Solution was to do a thorough measurement of room with REW, and complete rethink of positioning,. I haven't tried Dirac since, but it might do better with less to try to correct.)

It starts with electrical measurements (no passive crossover in place) to determine the drivers behaviour in the cabinet, resonance frequencies, natural roll-off and their phase response. Exakt then calculates the phase correction to make the drivers behave in a linear phase way.  My 21s were then measured in an anechoic chamber with each driver separately measured for SPL by frequency - this gives a plot which is then added to the model in the design tool. Exakt then calculates the linear phase corrections to even those out, but you put the anomilies in manually so there's scope for adjustment.

Crossover points and slope shapes are then done manually - using either experience or its possible to reverse engineer the passive crossover to get a starting point. This stuff is confirmed by listening and tweaking to taste. In my case I did this in my normal listening room so its not a purist approach, but it is a 'typical' UK living room and therefore a fair representation of a normal use case.

So a bit more scientific than you were suggesting but also encompassing some realism and personal preferences in the design choices. Not perfect perhaps, but then doing it all in an anechoic chamber isn't perfect either, as I don't know anyone who lives in one

I brought the point up because I thought the findings were relevant to the OP's experience and that it might be of interest to some. I added the Twenty.26 data as a contrast with the -15dB of the 21s. The -15dB is the average effect of the attenuation of the whole driver plus 2x baffle steps and some hump corrections.

I think my view of how the speakers sound using Exakt rather than passive filters is a moot point. FWIW I think they sound far more musical, sophisticated and refined on the top end. But I don't think that carries much weight as I clearly could be considered biased in my view, even if I'm not.  I'd really like to hear what Kudos did with Exakt filters on the Super 20s, but the opportunity has not yet been possible.

The comparison with Dirac is not really relevant. Dirac is attempting to correct for the speaker/room interaction. Linn's parallel to that is SPACE optimisation, not Exakt. Exakt is about eliminating (actually, it gets very close to eliminating) phase errors in crossovers and in the drivers themselves, plus correcting for anomilies in the drive unit response curves and some time of flight alignment too.  SPACE is a whole different topic.

Interesting, and thanks for taking the time to gibpve a clear explanation.

So Exakt is in effect building an active crossover from scratch, essentially  as the manufacturer of active speakers would do, albeit that Linn's approach may differ in practical details. I would certainly expect that to enable excellent control of the speakers, with optimised response. Clearly, however, this is not achievable by an individual user as they wouldn't have access to an anechoic chamber, somis this something that you have been doing toproduce a profile for Linn (or for PMC)? The ideal would be a response tailored to the listener's room, especially for difficult rooms - is there a facility for the in-room part of the process to be repeated by the user, to enable that? (Danger there of attempting to correct too much for room deficiencies, but that is going into too much betail for here. Also of course it can't correct for faults like early reflections and long decay times, so can't obviate room treatment if the best possible sound is desired)

However, although I personally I find this approach very interesting, I don't think that your measurements Are of any relevance at all to the original observation thatbthe sound is boring or fatiguing as they were made after removal of the manufacturer's crossover which would have been designed to balance the sound between the drivers and across the full spectrum within the limits of the particular model.

Simon-in-Suffolk posted:

Timo posted:

feeling_zen posted:

And while the Twenty range was fairly forgiving, the Twenty5 series take no prisoners and lay the system bare. I don't think 25.21 will take a liking to a CD5si - but I could be wrong.

I very much agree with Feeling_Zen. As I wrote in a different thread, I feel the 25.23 don't tolerate very well poorly recorded music -- and, as Felling_Zen suggests, weak links in the chain get exposed. My earlier Neat SX1 were much more forgiving. Well, I guess there is a price for the transparency and the excitement the Twenty5 series offers... 

hmm - but I didn't find the twenty5 series that transparent - the treble graininess (to my ears) held back definition and and subtlety - almost like it was quantizing the sound.... it was cathedral choir music that was shockingly poor - but play back recordings through different or possibly more capable tweeters and it all came alive and became credible when you shut your eyes .... i listened on Statement system and my more humble home 252DR system - and the effect was identical... perhaps it is only noticeable to certain people???

Simon

I think we've covered some of this ground before when discussing how different people have a different idea of balance and correctness based on what they have heard before that might be better in a certain respect to what they are currently auditioning. I am as sure as I can be (without transplanting your ears) that I know what you mean and have heard the effect you describe with the Twenty5 series. It's just that different importance is attached to it. I've heard a lot of speakers do very specific things better than the PMCs but then fall down in several other areas. I find them to be very good all rounders. While I find it fairly easy to find a speaker that does any one thing better than the PMCs for the same money, I find raising the bar evenly across the board requires a gigantic leap in cost. To me, in my system, they have the right balance.

I'm not quite sure how you get to "shockingly poor", but for sure, in terms of top end finesse I can think of a few that show the Twenty5s a pair of heels and if choral music was my staple I would probably be inclined to go for something like ESLs - I just wouldn't want to listen to the others (including ESLs) much for extended sessions on anything else. I think if you are used to a certain level and quality of delivery of a specific aspect, I would agree that there is no way in hell you can go back again even if other aspects are all brought up - the trade off will drive you nuts and leave you unhappy. This is why speaker upgrades that satisify (in my experiene) tend to fall into two categories:

• Uprgades within a brand you are currently using. Not always across the board improvement but rarely does performance in a specific area backslide (which is very noticeable). So you get a good improvement as you move up the range.
• Radical upgrades costing 2-3 times more than the current speaker and changing brand.

Regarding shockingly poor comment.. a few points... in my youth I was a church chorister, and I remember singing with choirs in cathedrals was one of the most spine tingling sensations I have had with music... and ever since  I have had a love and passion for church choral music especially in that environment with the complex reverb interaction of particular cathedrals ... now for the recorded music replay side... in my experience choral music is possibly one of the hardest music genres to reproduce... it ruthlessly exposes difficiencies such as artificial sybalence, blurring, compressed micro dynamics, tonal balance  and genereal lack of definition. Sure this has to be procvided by both the electronics and speakers and is clearly dependent on  the original recording and microphone placement and mixing, however all things being equal it does expose component difficiencies. Now I had been listening and auditioning to severel speakers in addition to my existing ATCs .. I like to keep an open mind and see what new is coming along ... so I had been listening to a pair from the PMC twenty5 series .. and it was here I noticed the difficiencies I described in a suprisingly poor way compared to the other speakers I was listening to including several cheaper than the PMCs. Perhaps on reflection I should retract the words 'shockingly poor' and replace with 'surprisingly poor'.

Innocent Bystander posted:

Interesting, and thanks for taking the time to gibpve a clear explanation.

So Exakt is in effect building an active crossover from scratch, essentially  as the manufacturer of active speakers would do, albeit that Linn's approach may differ in practical details. I would certainly expect that to enable excellent control of the speakers, with optimised response. Clearly, however, this is not achievable by an individual user as they wouldn't have access to an anechoic chamber, somis this something that you have been doing toproduce a profile for Linn (or for PMC)? The ideal would be a response tailored to the listener's room, especially for difficult rooms - is there a facility for the in-room part of the process to be repeated by the user, to enable that? (Danger there of attempting to correct too much for room deficiencies, but that is going into too much betail for here. Also of course it can't correct for faults like early reflections and long decay times, so can't obviate room treatment if the best possible sound is desired)

However, although I personally I find this approach very interesting, I don't think that your measurements Are of any relevance at all to the original observation thatbthe sound is boring or fatiguing as they were made after removal of the manufacturer's crossover which would have been designed to balance the sound between the drivers and across the full spectrum within the limits of the particular model.

I produced the 21 filters for myself but they will be available to others as Linn develop the tools further.

For the low end, I only addressed driver lumps and bumps shown in the anechoic plots. They therefore are not room related. The tweeter attenuation was done by ear. The crossover slopes started from the choice PMC had made with the passive crossover and then adjusted them by ear (for example, PMC had chosen a nominal 1800Hz but I found imaging improved a good bit but moving it to 1700Hz and it allowed some other improvements in addressing the high frequency humps in the mid-bass).  Both of these elements will include the listening room used, but, as mentioned earlier, it is a reasonably average room in size and surface / furniture mix.

I then use SPACE to address the room modes, I don't think there's much value in room specific crossovers, but it is possible.

I should also have mentioned that much of the harshness was addresses by that very early and very gentle roll-off of the mid-bass in addition to the tweeter attenuation.

If you're interested in more, keep an eye on news coming out of the Scalford show in March.

I'll stop writing about it here now because, although initially relevant to the OP, its getting a bit off topic now. PM me if anyone wants to discuss further.

feeling_zen posted:

No one's mentioned grilles. When all of my PMCs were new they were pretty heavy going for a few months and the only way to listen was with the grilles on. I even find the newer Twenty5 series need the grilles on to sound their best even after they have run in.

I have 21, 26 and C versions of the Twenty series. They're all well run in now, but I still prefer them with the grilles on.  But that might be just a psychological thing as I think they're a bit ugly without them

I wonder if the OP got himself sorted out ?

On the PMC thing .... I find that the twenty series (21 to 24) dry sounding in the midrange - I think this is something to do with the paper driver (my Rega Ela's) had a similar characteristic ...... I think PMC were aware of this. I would imagine this could effect choral music where the pitch in the upper midrange is critical .... I have not heard the 25's yet but I bet with the change of driver material ... the dryness will have been removed... I waiting to have a listen to a set of 25.21's. Generally - excepting that all speakers are compromises -  I think the little 20.21 is a fine little speaker ... that has a funky exuberant quality ... albeit at highish volumes ... at a point where it can ruthlessly expose the amplifier.

I have been away and on returning note the comments to this thread. Some appear pretty technical to me and not that helpful. However others contain easily doable adjustments that I will try over the next few days and report back.

Thanks to all who responded.

Try repositioning, tighter to the wall with no toe in ..... that should help reduce perceived  treble output and boost bass a bit... make sure your cables are neat .... there are some threads on this. Good luck let us know how you get on.

After experimenting for a week I can say -

There is no difference to my ears with or without the granite slabs , they stay therefore.

I have not tried to borrow from a dealer the PMC stands, so that is a possibility.

The cable I use is Chord Rumour 4 bi wire but with the appropriate bi wire -/+ strands on each length combined, I then use chord Signature jumper cables and Chord banana plugs. So speaker cable could be considered for replacement

I don't use the grills, I think they look better without and to me there is no sound difference on or off.

I have increased the difference apart by about six inches, they at about six and a half feet apart now, and they are toed in, inner rear 5 inches from the wall, outer 6 inches from the wall.

What has all of this achieved, not a lot really but the overall sound is perhaps a bit "sweeter", less harsh and a bit more to my taste. The biggest thing I notice is bass, particularly the quality of the actual bass player Phil Lesh, Nick Lowe or Jack Bruce say compared to the "lesser players. There is a better defined feel.

 Anyway I will carry on experimenting, cables perhaps but Naim are out of the question, they have to be white and pliable.

Charles44 posted:

After experimenting for a week I can say -

There is no difference to my ears with or without the granite slabs , they stay therefore.

I have not tried to borrow from a dealer the PMC stands, so that is a possibility.

The cable I use is Chord Rumour 4 bi wire but with the appropriate bi wire -/+ strands on each length combined, I then use chord Signature jumper cables and Chord banana plugs. So speaker cable could be considered for replacement

I don't use the grills, I think they look better without and to me there is no sound difference on or off.

I have increased the difference apart by about six inches, they at about six and a half feet apart now, and they are toed in, inner rear 5 inches from the wall, outer 6 inches from the wall.

What has all of this achieved, not a lot really but the overall sound is perhaps a bit "sweeter", less harsh and a bit more to my taste. The biggest thing I notice is bass, particularly the quality of the actual bass player Phil Lesh, Nick Lowe or Jack Bruce say compared to the "lesser players. There is a better defined feel.

 Anyway I will carry on experimenting, cables perhaps but Naim are out of the question, they have to be white and pliable.

 

 

 

It is good to learn you have an improvement.mcontinued experimentation may well improve further, both in terms of speaker positions, amount of toe-in, which can be zero or even negative, and listening position.

in trying to find suitable positioning in my room I used REW and shifted everything drastically at first, then speakers in six inch steps in, out, back forward, and listening position as well, each time having to repeat with speakers. I found near-perfect positioning for sound neutrality, which I define as my critical-listening position for both speakers and listening chair, and a less good but acceptable postion for speakers with a preferred seating arrangement, which is used more often, and finally there is non-music postion necessary when using te projection screen or for othervfamily use of the room, where the sound quality is compromised: I end up moving the speakers not infrequently, but that is the price I am prepared to pay. (Even with 48kg speakers it is not difficult, 'walking' them on their spikes, though I do have the benefit of a carpeted floor so no marking in so doing.)

I'm surprised you found no difference with grilles on or off. I've certainly found this to be true with some speakers but not the PMCs. I'd go as far to say that there is a marked difference in top end. 

It's great that you have other things left to try. However, my gut tells me that perhaps they are just not the right speaker for you in that room. I love the PMCs dearly but even the best of speakers can just not work in some contexts. While stands and cables make a difference, the fact that you noticed nothing at the top end when grilles were on leads me to beleive the problem you are describing is more extreme and that trying a different speaker entirely might be required.

I'm sure PMC recommend the twenty range fire straight ahead for the best high frequency response. It's in an interview/review with Peter Thomas somewhere I recall.

G

Agree with above do not tow in keep them straight ahead..... also try borrowing some std naim speaker cable.....