NrT upgrade completed!

[curtis]

King...did you miss this question?

King...do you use any kind of room correction?

[King]

King...did you miss this question?

Yes I missed it.

No room correction for any Sierra's. (2 channel system's)

Just My Home theater room uses room correction.

[curtis]

Yes I missed it.

No room correction for any Sierra's. (2 channel system's)

Just My Home theater room uses room correction.

Thanks..

Have you tried changing toe-in and out?

[GirgleMirt]

For example, I listened to Danny Gatton's "88 Elmira St." which is filled with Telecaster type guitar sounds. With the NrT it becomes a bit too much to handle for me at least.

Do you have a particular song with time to highlight the problem? I'm listening to http://listen.grooveshark.com/#/sear...lmira%20St.%22 the song "Pretty blue" on my computer setup and it does have a kind of quite harsh/annoying sound... Not sure if that's what you're referring to, but even if I haven't listened to it on the NrTs, just one of those songs I think will be 'annoying' to listen to on any neutral system... (non-tube, flat FR) Seems to lack bass, no 'meat', just harsh 'middy' sound...

And it is a tele... hehe.. Telecasters are known to have that kind of twang sound, and again it will depend on the actual guitar, the amp settings, mic, its location, mixing, and I don't know what else... Guit with distortion isn't usually the best reference. Even the sound of unamplified acoustic guitars can vary significantly just from guitar to guitar, and even with brand/type of strings, the pick, picking, etc. so again it's a bit of a crapshoot for evaluating recordings, and I say that absolutely loving playing and listening to guit... And that's not even taking into consideration the actual exercise of recording a performance... Or actually knowing exactly if for example the harmonics of a particular track are played just right or are highlighted by a system...

Other recordings with prominent violins can also exhibit this somewhat piercing quality. Again, it does appear very recording dependent.

Again, we have the same thing with violins as well as many different instruments, instruments can have a piercing sound to begin with and with the recording, mixing, EQing and all, they can end up sounding like velvet or be absolutely ear piercing... If the recorded sound is piercing, it'll sound piercing on a good system...

I listen to a lot of ECM Records releases that are always impeccably engineered and I haven't noticed as much the problem I describe.

Which again points to recordings?

I'm curious to hear Dave's answer if one is coming, but it might be interesting to run some sweeps or tones and see something is detectable... A piercing 'quality' could be some spike in FR, but even running some tones could probably be detected as one might be louder than others, or sound 'grating', I actually didn't bother to measure mine as simple listening told me everything was quite fine...

Again, I think that just identifying a specific track (Ex: on Track #3 of album x I hear 'distortion' at 2m30, or X instrument should be further back, etc.) could give a better idea. Of course would be best to all have the same recording and not use 'high quality' streamed music, but even that's better than nothing... I know a few here have the "chesky demonstration disk"...

2 days ago I was listening to out of others Yoko Kanno's "Flying Dragon" http://listen.grooveshark.com/#/sear...lying%20dragon where for example there's a lot of potential for ear grating and fatigue, the NrTs passed the test flawlessly imho... Same for "Dance of Curse" http://listen.grooveshark.com/#/sear...e%20of%20curse and pretty much everything else I've thrown at it... From Pink Floyd, R.Waters (boy amused to death sounds FANTASTIC on NrTs!!! ), King Crimson, Supertramp, Bach, SRV, Don Ross, D'Agostino, Montreal Guitar Trio, Dave Brubeck, the NrTs just give me the impression of "spot on"...

Again, I think the issue might be more the recordings... Even when you know very well a recording, what's the reference? Past playback systems? That could be problematic... Not the best example, but "Leaving on red hill" : http://listen.grooveshark.com/#/sear...n%20red%20hill surprised me, listen to about 1m30 - 2m when the tempo changes, strings join and then percussion and cymbals start. Could definitely sound 'too much', but that's just how it is...

I don't know... What's the reference for recordings? For me it used to be headphones, but mine have been surpassed by the Sierras so that's no good for me anymore... hehehe

[ctbarker32]

Pretty much the entire Danny Gatton record I reference is very hard to listen to on the Nrt. At certain points it comes close to hurting my ears! I'm not listening at high levels - maybe 80 db.

I'm going to start assembling a list of problematic recordings and will post over time.

I notice that DaveF has posted a response to King in the AVSForum. He implies that there must be something wrong but King's upgrades were done in-house by Ascend so that rules out that aspect. I did my upgrades myself carefully according to instructions and feel they are performing as intended.

One thing that could be worth exploring is if there is any sample to sample variation or problem with the Nrt Tweeters themselves. I don't know if DaveF said they tested each tweeter before they sent them out? Also, I guess that there could be something wrong with a component of the crossover as well?

The issue for me is that many recordings can sound wonderful but I can happen across a recording that just drives me up the wall with the ear piercing sound. It appears to be a very small frequency some where in the upper midrange that sets things off. I'm not convinced that it is just a problem of good/bad recordings. The Danny Gatton recording sounds fine on my Martin Logan Vantages and my KRK Rokit 5 nearfield monitors playing the exact same FLAC files from my server.

At least two unrelated people are commenting about what appears to be the same issue. While maybe not statistically significant it does suggest there may be something more here than random results would indicate? We'll have to keep testing to see if this can be figured out?

-CB

P.S One thing I wondered about during the install was if there was any difference in vertical alignment of the tweeter. Using the positive/negative terminals as a reference, I believe that I mounted the tweeters differently in each cabinet. I can't imagine how it would matter? The tweeter can only be placed one of two ways? But maybe I missed or am overlooking an important step?

[davef]

Hi CB and King,

Sorry if I have given you guys the impression that I am not paying attention to your comments. I most certainly am -- I caught a nasty flu bug about a week ago and I have been taking a cocktail of cold medicines just to function, but my head has been in the clouds as a result (not such bad thing)

We have done extensive listening to the Sierra-1 NrT and no matter what I have thrown at it; I have not been able to reproduce what you have been describing. I am most certainly not saying that you are not hearing it, but I have not been able to reproduce it.

Having said that, I have some Danny Gatton CD's on there way here so we can synchronize our listening.

Please check a few things for me...

1. Please run the system in mono and check each speaker individually for the piercing sound you have described. It is best to place the speaker in the middle of the room.

2. Double check the internals of the speaker. Make sure each crossover is firmly mounted to the bottom of the speaker and that nothing is loose or vibrating. If the crossover is not tight, the PCB can vibrate against the wood and this can create a multitude of problems.

3. Be sure all connections to the tweeter and woofer are extremely tight and that the internal cables are not vibrating against the cabinet walls. Also check that the binding post connections (internally) are extremely tight.

4. Let me know if you upgraded a newer Sierra-1 or one of the original Sierra-1's (a more difficult upgrade path)

These are the first steps to take and we will proceed from there...

I notice that DaveF has posted a response to King in the AVSForum. He implies that there must be something wrong but King's upgrades were done in-house by Ascend so that rules out that aspect. I did my upgrades myself carefully according to instructions and feel they are performing as intended.

Actually, I was not implying that something was wrong -- King's descriptions of the Sierra-1 NrT make it sound like an entirely different speaker than the standard Sierra-1, and it should not be sounding that way. The scientist in me is looking for possibilities as his descriptions are very different from the feedback we have gathered.

I am also not convinced that you and King are experiencing the same issue as King has indicated unnatural cymbal crashes that linger (amongst other characteristics) and that is usually an indication of room reverberation or sibilance in the system. I feel the Sierra-1 NrT reproduces the shimmer and decay of cymbals more accurately than the Sierra-1, with a bit less of a soft dome sound to them but also being more revealing. I do not believe you are having issues with the highs.

One thing that could be worth exploring is if there is any sample to sample variation or problem with the Nrt Tweeters themselves. I don't know if DaveF said they tested each tweeter before they sent them out? Also, I guess that there could be something wrong with a component of the crossover as well?

Every crossover and tweeter is extensively tested before it leaves our facility. In fact, each tweeter is first measured by SEAS (and recorded) and then we test it once again prior to shipping. I honestly do not suspect a problem with the tweeter... While tweeter problems can arise (they are highly mechanical devices), problems are not typically limited to a specific frequency range nor would they be recording specific.

If there is a problem, it is more likely in the crossover. For example, while we fully test the crossover prior to shipping -- flexing of the PC board itself during shipping and subsequent installation can indeed cause problems. A good example of this is if upgrading from the original Sierra-1 where the new crossover will not fit into the original mounting holes such that it is mounted differently and quite possibly under stress or has been stressed (flexed). Stress on a component lead (especially a capacitor) can cause many different problems. Unfortunately, these are things we can not test for in the factory, but thankfully -- we are running very impressive numbers right now for even customer performed upgrades

While there could indeed be a problem with a crossover component, we must also realize that there might not be a problem at all and the speaker is performing to spec. The frequency range you are describing is one that the human ear is most sensitive to and more information in this range from the Sierra-1 NrT simply might not match well with your hearing. We can not and should not use our own ears as a reference. The shape of our head, the shape and size of our ears and ear canals -- amongst so many other variables -- greatly influences how we hear. And when comparing to other speakers, one must compare the entire frequency range and not just one range of frequencies. For example, if you hear some piercing sounds with one speaker in a specific range compared to another on a few specific recordings, on a different recording, how do the two speakers compare to each other? Which speaker reveals more detail and sounds more accurate overall?

P.S One thing I wondered about during the install was if there was any difference in vertical alignment of the tweeter. Using the positive/negative terminals as a reference, I believe that I mounted the tweeters differently in each cabinet. I can't imagine how it would matter? The tweeter can only be placed one of two ways? But maybe I missed or am overlooking an important step?

No, the vertical alignment of the tweeter will not matter at all.

I feel the best way to proceed from here is to run through the few checks I listed above and if nothing changes from there, I would very much like to arrange to get your speakers sent back to our facility for measuring and then a comparison evaluation with our reference set of Sierra-1 NrT, using the same music selections you have described as being piercing.

Please send me a PM or email (email is preferable) and we can move forward from there.

I should also mention that all feedback is greatly appreciated. While it is impossible to manufacture a loudspeaker that everyone loves, we do want to try Your feedback combined with our know-how and resources are the blueprints for our products.

[ctbarker32]

Thanks Dave for the very detailed response and ideas on how to proceed. I am going to spend this weekend following your steps to check out my speakers and will report back my findings. While I did do my upgrade myself, I did do it carefully and watched the videos and believe that it was properly installed. I will check though, as you suggest, if something has changed since I did the upgrade.

I did some serious listening again and took some notes while scrolling through my music collection. It is really puzzling to me that on some tracks the NrTs sound alive and great and then listen to another track and hear the piercing sound I describe. I don't believe it is just a question of good/bad recordings. I think it is more a matter that some tracks don't have an abundance of sound energy in the frequency region that is bothering me.

From my listening notes:

Listening to a number of Alison Krauss & Union Station cds. My experience is these are impeccably recorded. From the "Lonely Runs Both Ways" cd, song Restless, I really notice a "raspiness" on AK's voice I was not previously aware of. I listen to the same track on my Benchmark DAC via Sennheiser headpones and do not hear the raspiness.

I also notice a lot of "shhh" sounds that seem overly emphasized. Sibilance? Another example is the new album by Pierre Bensusan "Vividly". I became aware as I listened to the vocals on this album that it sounded like the singer has a lisp. I have listened to him for decades and seen him live. He doesn't have a lisp. When listening on the NrTs he has a lisp?

Listening to Norah Jones Come Away with Me I again hear some "raspiness" in her voice I was not previously aware of.

Changing music style I listened to Bill Bruford's "Feels Good to Me". This is an old cd that was mastered before the loudness wars and thus needs the gain set higher to fully enjoy. The cd sounds quite good and the NrT clearly reveal the analog tape source (hiss) of this recording. Lots of mallet instruments and drums/cymbals. The guitarist Allan Holdsworth is prominent on this recording. On the NrTs with the rest of the album at an an appropriate volume the guitar borders on piercing. I have never experienced this with this album before the NrT and I know this album like the proverbial back of my hand.

Here's one more example. Listening to the Grateful Dead's Mars Hotel and the track Unbroken Chain. This track has an odd sound throughout the song that sounds like an airplane landing sound. Before listening, I anticipated this might cause the piercing sound I hear but to my surprise the track sound good and balanced except - Jerry Garcia's guitar borders on piercing!

So, I don't know if I have helped describe what I'm hearing or not? This is the most puzzling speaker evaluation I have ever experienced. I consider myself a really dedicated audiophile and spend most of free time practicing my hobby. I do appreciate Dave's attention and I hope I do not send him on a wild goose chase but I do feel confident of what I am hearing in my system.

Thanks.

-CB

[ctbarker32]

Please check a few things for me...

1. Please run the system in mono and check each speaker individually for the piercing sound you have described. It is best to place the speaker in the middle of the room.

Okay, I have performed this initial check. Set my preamp to Mono, disconnected one speaker at a time. Took the grills off. Listened carefully to Gatton's "88 Elmira St" cd. Both speakers sound identical. Same piercing sound. At least this eliminates that one speaker is somehow defective or out of spec?

-CB

[Quinn]

The "raspiness" and the ssssh of sibilance aren't introduced by speakers but are revealed by some. To me it sounds like you're getting more revealing details with the NrTs that the the regular Sierras weren't able to reproduce and those extra details aren't to your tastes.

Norah Jones has never been embraced by high end audiophiles due to what you talk about since their systems revealed it.

I seemed to remember that when the Sierras came out there were a few posts/threads about discovering how poorly recorded some people's favorites were.

[GirgleMirt]

Well some speakers add sibilance but I haven't noticed it with the Sierras... Listened to Gatton's song I've linked earlier but in lossless, and for some reason seems to sound better in the low registers (better balance) than the grooveshark version... Definitely less harsh too.

Anyhow, I can still detect a sort of harshness, but can't really explain it... I hear the same thing on my NrTs as I do on my nearfield computer setup so really think it's related to the recording. Other records don't have that same thing... I've checked the file in a wave editor and although I'm no expert it looked fine to me, not really clipped, and unlike the the compressed groove shark version it wasn't as bass anemic as I first thought...

Maybe it's some sort of high frequency noise? What's weird is that I can't really pinpoint the 'harshness' in terms of precise sound but still something in that recording that's definitively sort of annoying... (sort of ear grating) Or yeah, maybe it's in the midrange, I don't really know...

Switch record and it's gone though... If it was speakers, I think I'd have heard it with other records and wouldn't have heard it on a second setup... Did you say you never heard the same thing on other setups? Weird...

Had half typed a reply a couple days ago but Dave already answered most things..

The issue for me is that many recordings can sound wonderful but I can happen across a recording that just drives me up the wall with the ear piercing sound. It appears to be a very small frequency some where in the upper midrange that sets things off. I'm not convinced that it is just a problem of good/bad recordings. The Danny Gatton recording sounds fine on my Martin Logan Vantages and my KRK Rokit 5 nearfield monitors playing the exact same FLAC files from my server.

2$ on recording

Martin Logan... Hmmm.... I don't know if electrostatics are the best reference... I'd point out more to speakers like JMLabs Utopias, Dynaudios, or whatever, or whatever uses a high end tweeter... It's just that eletrostatics sound so different... KRKs again isn't the best reference, there's better studio monitors out there, probably aren't as resolving as the NrTs...

Don't want to blame other speakers for not hearing it, but I'm pretty confident that if you went to a shop and listened to that track on different high end setups you'd also hear the issue... Are you sure you don't hear it on the KRKs? ML's are so different they might not reproduce that same hashness as I think they're really not speakers which will ever sound harsh... Instead always sound like if the audio image was only semi tangible... Never "in your face" kind of sound, even if the recording dictated that the sound should be right in your face... (Well can be 'in your face', just not in the same manner as dynamic speakers...)