Thiel Owners


Guys-

I just scored a sweet pair of CS 2.4SE loudspeakers. Anyone else currently or previously owned this model?
Owners of the CS 2.4 or CS 2.7 are free to chime in as well. Thiel are excellent w/ both tubed or solid-state gear!

Keep me posted & Happy Listening!
jafant
Andy - internal wire is definitely a factor. It carries a slightly different set of requirements from external cable, which must cope with many unknowns of run length, electromagnetic environment, speaker impedance fluctuation, and more. The internal wire is engineerable to the known requirements of the speaker where it is installed.

Thiel wire is very good. In fact, Thiel "found" wire as a design variable in the development of the O3 in 1978 and introduced aerospace wire to the industry. All models of Thiel wire is, and has always been since that time, 99.9999% pure, low oxygen, long crystal copper developed originally by ITT for the space project, and since then cloned by many makers around the world and now improved by continuous casting and other advanced technologies. I'm guessing that Thiel wire trumps all but some of the highest cost and/or DIY speakers out there. 

Although various configurations are appropriate for hookup wire, Jim chose 18 gauge solid in teflon @ 2.5 twists per inch as a well considered judgement of maximum versatility. Economy of scale was a major concern - good wire is very expensive and big order quantities reduced cost, so all hookup wire is the same, and therefore might stand upgrading via specific-use engineering. More on that in a minute. Beyond hookup wire, the same quality criteria apply to coils. The signal meets hundreds of feet of series and shunt coils inside the speaker. Thiel uses 6-9s copper coils, tightly wound and oven baked. Great coils. In Thiel's and  third party testing, our wire and coils are best-in-world performers.

However, it's never that simple. In the present XO upgrade project I have learned that later speakers including 2.4's were supplied with Chinese-made crossovers. The copper (and other parts) is supposedly a clone of Thiel Copper, but it is not certified and my research causes me to doubt the claim. The coils are obviously lower grade manufacture as learned from Beetlemania's work on his 2.4 upgrade project. The resistances and topologies of the wire and coils are all good, in fact the coil values have been tweaked to account for inductive changes with Printed Circuit Board mounting. The XO performs properly, but sound quality probably suffers a little, as ascertained by Thiel insiders.

My plan is to evaluate the source of each XO encountered to decide whether to keep or replace particular parts. Beetle's late 2.4s have every element replaced. My 2.2s keep all coils and French-film PolyPropylene caps and German Styrene x Tin foil bypasses. My PowerPoints include a Lex and a China pair. Lex are better and will retain some parts. No China parts are being reused. It's a riddle which I am systematically solving.

Another element is wire gauge. Lower resistance is the primary reason for larger wire. However, the overall circuit resistance from input terminal to driver lug is measured and accounted for in the XO, so resistance considerations become nearly insignificant. Our upgrades are increasing some (woofer) hookup wire diameters for greater ion flow optimization. Coil gauge is only changed where required for foil cap upgrade availability. Contrary to some opinions, the small gauge shaping coils are superior to larger gauges, because they can be tuned to their parallel resistor for balanced resonant circuit performance.

I am accounting for wire and coil resistance changes, which may sometimes require a resistor value tweak for proper system performance. Project process is being made. We'll have more to report when the Thiel Audio bankruptcy settles.
Beetle - that is correct, the twisted pair wire I sent you was sourced from StraightWire, which is an industrial as well as OEM and consumer source. As you mentioned, we will be comparing that wire in various gauges against other contenders when that time comes.
This is outstanding information, Tom.  Many thanks.

I was aware of the Solens that the crossovers were often fitted with.  Can you add anything as to the electrolytics Thiel has used over the years? 

I say this because typically electrolytics do have a serviceable time window before capacitance starts to shift, and techs tend to focus on them when addressing older instruments.
Sgmlaw - indeed electrolytics are an issue; they fail over time, drastically and sometimes catastrophically at the end, but also by decrease of value over time, as you say. ELs show up in 6 figure speakers, it's expensive to avoid them.

So, a 30 year old speaker XO has almost surely drifted out of spec, as well as in some level of danger of failure. Rob says he has never seen a failed Thiel cap so far. Thiel used VersaTronix and ERSE, both in their long-life versions with a predicted life of 30 to 50 years. All are bypassed in some way, which extends main cap life more so.

All that said, I am replacing ALL electrolytics to create an effectively "permanent" XO, comparing cost / performance at this time. The likely first-tier upgrade will use ERSE metalized polypropylenes @ highest voltage that will fit, bypassed or not depending on function. Next-tier upgrades will be to a custom ClarityCap CSA - expensive, but stunningly high performing - again, bypassed or not with Cornell Dubilier PPs or RTX styrene film and tin foil, depending.

Early indications sound like we'll be playing a league or two up from original Thiel. The view is getting clearer. 

internal wire is definitely a factor. It carries a slightly different set of requirements from external cable, which must cope with many unknowns of run length, electromagnetic environment, speaker impedance fluctuation, and more. The internal wire is engineerable to the known requirements of the speaker where it is installed.

I agree.  For most cases, the internal wirings are much shorter than the external speaker cables, therefore I think it is less likely to modify the signal phase and amplitude vs. the external cables.  Some of the expensive speaker cables nowaday I have seen have rather sophisticated geometry and dielectric core material and grounding that together act like a transmission line to deliver the signal as uniformly as possible across all frequencies.  Some people think that audio frequencies are too low to be affected by transmission line but I do not think so.  Some lesser cables may have resonance issues and the effect is exacerbated as the length increased. 

Some believe that the only difference between cables is the resistance.  I think it's more than that.  You also have the effect of inductance and capacitance - the longer the cable the worse the effect.  A perfect cable should deliver the signal from the amp to the speaker input with a constant phase and constant amplitude losses across all frequencies, but since there is no perfect cable (or is there?) by the time the signal arrives at the speaker inputs, the phase and amplitude will be affected differently vs. frequencies.  This affect materializes itself as a form of jitter (although there is more than just jitter)  A good cable has better phase and amplitude uniformity compared to a bad cable.  Some speaker cables are engineered to intentionally have a transmission line affect so the signal phase and amplitude can be better controlled by the designer.  With twisted pair, the number of variables  is somewhat limited by the wire gauge size and number of winding per in. therefore it may not be able to optimize signal transmission. 

In some speakers, the xover boards are located at the bottom so the wire to the tweeter could be as long as 3ft.  At that length, there could a transmission line like effect that may modify the signal phase and amplitude non-uniformly vs. frequencies therefore the quality of the cable is more important.  But I have personally seen that something as short as 1.5ft length could make significant difference with quality cables.

Anyway, I don't mean to make this into a cable thread (I don't want prof to loose his sleep :-).