Thiel Owners

BTW, as someone who has numerous speakers, spade connectors drive me nuts.  I much prefer bananas for the ease of use.

@prof How often do you swap connections? Spade connection is tough to beat for a solid transmission of the signal. Set it and forget it. 

Well, I used to swap more often than I do currently.  Maybe once a month or so.


And previous to that I used to do it almost every night.   That's because I used to use my home theater (Hales) speakers for two channel as well.  So I had speaker wire leads from my tube amps sitting near my HT L/R speakers, and when I wanted to use them for two channel I'd just unplug the speakers from my home theater cables, and plug in the cables to my 2 channel tube amps/sources.   So banana plugs were very easy to deal with. 


Still...I own at the moment 5 pairs of speakers that I swap in and out, so any connection that makes that easier is the one I prefer.

I'm a fan of having a couple of sets of speakers or a couple of systems.  I think there is some difficulty in getting a single system to do everything well.  Thiels excel at lower to moderate volume, acoustic music.  I don't use them to really crank, though.  I've got some active ATCs for that.  They don't sound as nice at low volume or image as well but they will play very loud without distortion or fear of breaking anything.  That's what they're made for.  I can get on my 17 year old noisy treadmill and crank up something loud enough that I forget the treadmill even makes sound.  It's fun.  

jon I crank my 3.6's and CS6's.  The 6's  play louder, the 3.6 play plenty loud and are ever so slightly more transparent!

I hear you with your ATCs I have the old Polk 2.3tl's that I bought in the 80's that I refurbished.  Fun to put them in sometimes because they play "listening to live music in bar" loud!  Not nearly as good as the Thiels but fun.

another comment from my friend using the Goertz cables with the 3.7's.

One more thing to add to the list. Not sure exactly how this works but the background with the Goertz is blacker. The music just emerges from a very quiet place. Not sure why this would be so? Didn't think of speaker cables as adding noise? Maybe the Zobels are getting rid of some high frequency hash?

The Goertz design is high-capacitance, which may cause some amplifiers distress in the trans-audio high frequencies, which produces down-reflected audible consequences. Correcting that capacitive load makes the amp run truer to form.

thanks Tom.   is that true for shorter lengths such as 8' as he is running 13'

Ron, shorter cables are always better than long. But parallel (not twisted) conductors like Goertz are inherently capacitive. If there is a problem depends on the amp. But Thiel's low-impedance results in more current being drawn through the cable, so any capacitance problem is likely to be exacerbated. I suggest using the Zobel filter.

thank you so much

FWIW:

I had a very long run for my speaker cables (my source equipment is in a different room) so I went with Belden 5T00UP 10 awg cable (bought from Blue Jeans cable).   The specs were excellent and just what I needed for long speaker cables without loss of sound quality (see review with test results):

https://www.audioholics.com/gadget-reviews/blue-jeans-10awg-speaker-cable-5t00up

I regularly listen to my pal's system wired up with more than $20,000 in Nordost cabling (he used to have my cast off speakers, too, in that system)  but my system sounds darned good to me!   And I think it's fair to say I'm a picky listener :-)

Good to see you - profHappy Listening!

Good to see you - tomthiel
Happy Listening!

good to see you - ronkent
Happy Listening!

Good to see you - jon_5912
Happy Listening!

Good to see you - beetlemania
Hope you are well, enjoying Summer and having fun with those XO projects.
Happy Listening!

Good to see you - pops
Happy Listening!

Ok, jafant....I just can not read your last line up of posts and not think of a previous quip someone had made.

Along those lines, if your current source of employment dries up I think you can slip easily into another similar gig:

https://www.job-applications.com/walmart-greeter/

I kid...I kid....;-)

Annoying, isn't it?

okay guys,   spill the beans.  am i the only one here who has had issues with the coax drivers in the x.7 series.   as i mentioned earlier i have had to replace three of them in the 2.7's but none yet in the 3.7's.  earlier models never had an issue.   inquiring minds want to know.   thanks.

tmsrdg
If you are annoyed, move along to a different Audio forum.

prof
the quip in question was in very poor taste.

ronkent
Have you consulted Rob Gillum? Perhaps he can shed a little light on your query.  It is an interesting situation. Keep us posted as you find answer(s).
Happy Listening!

thanks,  but it would be interesting to see who else has had a problem with blown drivers in the x.7 models.  i certainly cannot be the only one but maybe i am.   i play my music loud but my girlfriend who does not like it too loud,   rarely says anything to me.  usually 80-85 db

Ron and all. I placed a query to Rob via phone message this morning. I will post what I learn. This information is indeed germane to all on this board.

I blew the midrange on my 3.7s the first few months I had them.  I was listening to Beethoven The Revolutionary loud.  I took the driver out myself and it didn't look scorched or anything to me.  That was back in 2012 and they've been fine since then.  They were an early pair I believe.  The serial numbers on the boxes are 41 and 42 I think.  I bought them used from Audio Consultants so it's possible they weren't the original boxes that came with the speakers.

Folks, for those who blew drivers, like the 2.7/3.7  coax, what were the sonic symptoms?  Did the sound just die?  Or did a crackle develop in the sound....something like that?

(The only driver I've ever seen damaged in my home is, apparently, one of my Hales T1 monitors which plays the R channel in my home theater.I think it was hit with some too-heavy bass at one point and these days, although it sounds fine with most material, a super low/heavy bass signal will make it pop and crackle).

When my 3.7 mid blew it made a very noticeable scraping sound.  

pops, I love both the ATCs and the Thiels.  Both are great products intended to be as accurate as possible but with somewhat different ways of going about it.  ATCs are usually active and the company is mainly known for pro audio.  ATC has been building its own drivers for a long time and their philosophy is that if you build drivers well enough you don't need a complex crossover.  I think Thiel is not that far from that.  Thiel produced passive speakers for home audio so they have different strengths.  Thiel had complex crossovers for a long time to fix drivers that weren't as good as they could have been.  When Thiel came out with their own drivers the complexity of the crossover dropped significantly per Tom Thiel in this thread.  

The founders/designers of both companies were piano players.  They're both hard science guys.  I get the impression that Billy Woodman isn't quite the obsessive perfectionist that Jim Thiel apparently was. Both companies use small diameter midranges which I've found that I prefer. Not sure why, lighter weight leads to faster response or maybe better dispersion.  

Prof: " Folks, for those who blew drivers, like the 2.7/3.7 coax, what were the sonic symptoms? Did the sound just die? Or did a crackle develop in the sound....something like that?"
first time:  scratchy sound though i think it was bad from the get go as it happened within two months, or perhaps the amp, a Marantz reference,  was not up to par.2nd time:  with BHK amp-got the crackle you referred to and it was really obvious something was wrong and Rob said it was blown.3rd time:  with BHK-weird as it was more of a hum,  almost like the unit was singing with the music, but it added something really weird to the sound.  Rob can usually fix them but this one stumped him if i recall. 

thank you Tom.   maybe you can get Rob to join us here.

prof: I have to agree with you. I'm running 23 feet of 10 gage Blue Jeans cable between a Bryston 4Bsst2 and a pair of Thiel 2.7s

Couldn't ask for anything better, including the cost of having Blue Jeans make them for me - - and with spades. 

Yes brayeagle, it’s great to have custom made stuff from Blue Jeans. I’m going to have some interconnect made, short and long.


They have really low capacitance interconnects which is great for some long runs I need, especially to my subwoofers. Though admittedly the really low capacitance of the BJ cables may be overkill for a subwoofer signal which is being low-passed ...what the heck...a little over-engineering never hurt.

Had them make the interconnects from my preamp to the amplifier

Ron, all of your failures sound like overheated voice coils, either delaminating or in the case of humming along, being loose enough to squirm on the former. The cause is most probably being fed a distorted / semi-clipped signal. The first driver was probably good out of the box and also failed via underpowering.

thanks Tom.  i guess i play them too loud but i measured and the average is about 78 db with peaks of 85.  plus the PS Audio BHK 250 amp is a hoss.  I will have to be more careful  but interestingly enough,  in the past using lesser amps with the older models, and playing at the same levels,  they did not blow.   my  guess is that the newer coax is just a bit more touchy.  thanks so much for being on this thread.  

tomthiel,

What is the role played by the difference between tube amps and solid state amps, which it comes to damaging clipping?

It’s something of a cliche to say that tube amps clip more softly than SS.Is this true to the extent that it would be less likely to get damaging clipping from a tube amp of comparable power to an SS amp?

I’ve used tube amps since the 90’s . I’ve had a great many speakers, some as insensitive as 82dB and impedance all over the place, and I’ve played them loud.

But not once have I ever blown a driver. So I’m wondering if this has much to do with my choice of tube amplification. (I use Conrad Johnson Premier 12 tube monoblocks - 140W side).

good question Prof.

Did any of you consider Luxman amps to drive your Thiels ?If so i would like to have feedbacks.I have been told Luxman would be a very good match.I'm looking at this model : http://www.luxman.com/product/detail.php?id=19

i have no knowledge of Luxman but that looks like a beast to beat the band.  how much

Ron, your listening levels and amplification are very appropriate / safe. So something else is going on, perhaps bad drivers, but sometimes cables can induce amp misbehavior that adds stealth distortion. I can't troubleshoot, but I will try to find out the service history of those drivers.

Prof, that cliché is true. Tube amps clip softly, without much hash, and therefore are far more gentle on speakers when driven hard than most solid state designs.

As an aside, I have played hundreds of Thiel speakers for thousands of hours, often in very demanding and loud situations, and have never blown a driver . . . I have also seen hundreds of "blown" Thiel drivers and in the vast majority of cases the voice coils are burned, which is (practically speaking) only caused by distortion (the driver will produce ear-piercing volume without damage given a clean signal.) Those burned coils are user-damage, but Thiel generally covered them ONCE under warranty as good will. Legitimate manufacturing defects include subtly mis-routed lead wires, magnet-position and/or suspension mis-alignment or glue failure, etc. Those are generally batch problems and result in instant failure (broken lead) or immediate voice coil rubbing. If it's defective it will fail quickly.

Part of my upgrade project is thermal management, which is generally ignored in hi-fi, but is very important in sound reinforcement and pro-audio. Heat is a real enemy. It can shift crosspoints radically, which adds substantial stress to the system. A 3KHz tweeter crosspoint can migrate to 2500, admitting damaging low frequency signal to a driver which is vulnerable due to the concurrent high-power situation.
So, I am mounting all resistors in heat-sinks mounted to buss bars to dissipate waste crossover heat. My CS2 2 workhorse is getting an aluminum tube spine up the back of the cabinet to sink those buss bars as well as mounting an aluminum tube from the back of each driver which conducts heat as well as provides more mechanical stiffness to the driver mount. I am puzzled that Jim abandoned aluminum voice coil formers for nomex; probably for lower mass and smoother high frequency extension. But thermal conduction was traded off. This note is just to let you know where my investigations are leading.

BTW, I have a pretty big pile of foil coils, resistors, wire and caps, plus the Clarity Caps are finally on their way. I'm especially excited about a CC custom polypropylene cap we have developed to replace all the electrolytic caps. I'll be comparing the new CC to the ERSE PulseX Polypropylenes in those applications. Either way is a big step up from the present electrolytics in the shunts. Progress is being made. 

thank you again TT.   your input here is so appreciated as is the research you are doing.  it is a puzzle to me why i have had bad luck with the coaxes in the 2.7's, and maybe it was a bad batch.   i use Analysis Plus speaker cables and they are only 8' runs.   the first driver that blew was used with a Marantz reference amp,  so no slouch,  but the second and third were with the PS amp,  so i doubt i drove it into clipping.   i have issues in the right ear and it will buzz like a tweeter when the  music is played too loud.  sort of my canary in the coal mine  thing.  maybe it is a thing of the past now that i have 3.7's which i think are less demanding on the amp due to the higher input sensitivity. i have had to  dial back the preamp from an average listening level of 39 to about 33 (PS BHK preamp).

Tom, that's more helpful info, thanks!
Now to go crank my tunes!....

I'll try to find out something from Rob about the 2.7 vs 3.7 failures. Same driver.

Thieliste, good investigation. In the day Thiel, especially the CS5, was very successful in Japan. Luxman amps were the clear choice in ultra high-end systems. They are seriously good. The amp you reference is still doubling into 1 ohm, and their engineering choices are musical (most Japanese amps are not, in my opinion.)

Ron, I see from the XO schematics that the higher input sensitivity of the 3.7 is due solely to its more efficient woofer. The 2.7 coax has resistors to pad it down to a less efficient 8" woofer with the same coax. No satisfying answers yet.

thanks Tom,  that is interesting if i understand correctly about the resistors.  when i sent back the last damaged coax to Rob,  he sent the replacement back with a resistor on the positive terminal.   to the best of my recollection,  none of the others had that resistor.  could the lack of that resistor make the drivers more prone to damage?

Ron, I don't have enough history to comment on your situation. I am far away and out of touch and coalescing probabilities from sketchy evidence. The detailed lab records are MIA and most of what we know is in Rob's memory. I am gradually back-engineering XOs and timelines from photos, previous suppliers input and whatever Rob sends me. Rob says that Thiel built all 2.7s in Lexington under his supervision, so he knows far more than I do.

The schematic that I created from an engineering layout shows the tweeter with a parallel pair (20+3) netting 1.3 ohms in the tweeter series feed. It is possible that value was adjusted over time. Rob would know his rationale and I do not.

Excuse me, that's 2.6 ohms.
TT

hi Tom,  my  understanding of this is bare bones at best.   i did replace a few coaxes and do not remember seeing any with a resistor on the positive terminal.   could that be a reason for my proclivity to blow drivers?  When i sold my 2.7's i sent the extra coax that i had for it and it did have the resistor as it was my back up driver.