power for Thiel 3.5's


People I trust have suggested many, I think I've narrowed it down to the following: c-j 2300/A, 2500/A and Threshold s 500 II. The TacT gear sure is interesting to me as well. I could replace the supplied equalizer with a more modern one that would boost in sympathy with my room. There would be little fear of pushing the speaker beyond it's limitations as they were designed from the get go for such treatment. The best amps I've heard on these speakers are the Krell KMA 160's. I think with an appropriate line stage they may be out of my budget. I'd like to stay +/- $2500 for both pieces, maybe $1500 for the amp and $1000 for the line stage? This may seem silly, but my asthetic sense would prefer gear that doesn't have extras I won't use such as bi-wiring and balanced ins and outs. I also would prefer something with out fans. The Thiel 3.5's use an active equalizer with RCA only inputs and out puts that boosts frequencies below 70 Hz by up to 12 db. The equalizers input impedance is 91k Ohms and output impedance is 130 Ohms. The speakers are quoted as having a 4 Ohm nominal and 4 Ohm minimum impedance. Independent testing has shown this to be fairly accurate, with a small peak between 8 and 10 Ohms at about 33 Hz. The speakers are rated as 89 db in sensitivity. I'm presently using a solid state c-j amp that is rated at 80 watts per channel into 8 Ohms. My current roomis 23.5' X 11.75' with a ceiling that peaks at 14'. I place the speakers along the long wall firing across the short wall. I find that at louder volumes the sound begins to get hard. I think more power is needed. I don't listen at ridiculously loud volumes, but, I do like to play at a scale of volume that is appropriate to the room vis a vis what I suspect was the original venue. In other words louder than most folks but not as loud as many audiophiles. In my opinion the few problems that these speakers exhibit is a little courseness in the treble compared to the best modern designs, a little softness in the region between bass and mid range, a slight percussive ringing in the lowest bass and some limitations in ultimate loudness. This may seem as though I don't like them, nothing could be further from the truth. I've tried to aquire an after market equalizer (golden flutes) that might have offered the chance to use balanced gear, but have not had any luck as yet. Any suggestions would be appreciated, especially if you can consider a matching line stage.
unsound
I should add that the Thiel 3.5's can occasionlly sound a bit pinched in the low treble and despite the quality of the low frequencies sound a bit tilted up. This tilted up sound is not as prominent as some other Thiel speakers. I suspect this is due to the sealed box design and overall superior bass balancing out the overall sound.
Hi Unsound-
My vote goes to the Threshold.
My S/300 was by far the best amp I used with my 3.5's
You know the 2 others.:~)
I currently have two pairs of Thiel speakers and have owned them in the past. So you could say I am familiar with the Thiels. I would look into the Threshold T-400 ($1,600-1,800)power amp mated with the Threshold T-3 ($800-900) pre amp. They will end your search and allow you to sit back and enjoy the music. Good luck with your search.
I have been using the cs3.5 without the equilizer for years with a much much more neutral sound. My amp is a tube power 100 watts ARC, pre is AI M3, and an ARC cd2 and VPI MK 4 table with Benz cartridge as source. There is plenty of volume and low frequency, treble is crisp, voice and mid range is sweet and not bright at all. I also have a big room 30' x 25' with vaulted ceiling. Previously I have used a Counterpoint SA220 modified amp, and have good results, but I prefer the ARC tube amp as I can switch tubes for tuning the sound. Good luck to you!
I'll relate that I listened to a pair of Thiel CS3.5s at Innovative Audio with the Krell KSA 80 amp I wound up buying for my Duntechs about 15 years ago. I thought it sounded fine, and I knew for my Duntechs a solid-state amp was what I wanted. As I was leaving a customer came in and listened to those same Thiels with a Conrad Johnson Premier 3 or 5 amp (whatever their top of the line at the time was). I think that was the moment I first realized just how good tubed amplification is--the midrange was absolutely gorgeous. I have never heard the Thiels sound better than that, either before or since. If you're not adverse to a tubed amplifier, and can live without ultimate control or extension in the bass, I would consider going that route. If not, the Connie J solid state might be a good, though perhaps a bit polite, match.
I owned 3.6s and had a two year problem with them drilling holes in my ears. The speakers were great but my ARC LS2B was on the bright side and not a good match. I got a Sonic Frontiers Line3 and the speakers got much better. Although I've never used Threshold gear or auditioned it I would warn you to go tube pre and amp if all else is equal. The Thiel's need a warmer set of electronics...do stay away from anything that is described as bright analytical etched etc with these speakers. (I am not a tube guy perse since I currently don't own any tube electrons except an ARC PH3 phono pre.)
Two years???!!! You have much more patience trhan I my friend. Those would have been out the door or new amplification would have been in the house in about a month. I have also heard that tubes can make the older Thiels sound a bit more true and not so bright. Sounds like if you are sticking with older Thiels they are the way to go.

PS. I've heard that the Primare gear can sound superb with Thiel also......or a Conrad Johnson tubed pre.
I own a pair of 3.5's and as you know they need an amp that can deal with their first order crossover and impedance curve. The amps you mention are good ones. I have found Classe amps to be a good sound match to the thiels. The CA 300 can be had for 1600 to 1800 used. Several appear on Audiogon. It can be switched for use as a monoblock or stereo. The sound is warm and fluid much like a tube amp. Yet the Classe has the punch and tight bottom end that can make a thiel perform as they were designed to. Rated at 300 per channel, that doubles into 4 ohms. I use a subwoofer with mine and let the 3.5 roll off naturally, not using their equilizer box. Built like tanks they weigh about 80lbs. Excellent reliability. The CA 300 is not currently in production, but Classe has an excellent service department. Contact Armin Gschwendtner (customer service manager) at Classe Audio Inc. (514) 636-6384 if you'ld like to verify specs. and performance.
Email is www.cservice@classeaudio.com
If you like the Threshold amp, you'll really like the Classe.
Any one know of a suitable amp for the Thiel 3.5's that can provide 500 watts into 4 Ohms? I've heard Classe' on the Thiels, while Classe' would make my short list, Classe' may not be at the top of that list.
A Krell 300cx will provide 600 WPC in to 4 Ohms and 1200 WPC into 2 Ohms. The cx series of Krells is one of the best choices for Thiels.
hmm were it me I would opt for a softdome tweeter from morel or vifa, using the same electronics and allow myself the bliss of the saved cash. www.partsexpress.com offers some very good stuf that will "fix" your hi-freq problem in a manner of days. check them out
Alpha 03, thanks for your thoughts, but, I think you might have the wrong idea about my quest. While the Thiel 3.5's soft dome tweeter might be a little crude compared to the newest tweeters available, and while the sonic signature might be a little tilted up, I wouldn't dream of tampering with them. The tweeters are extended and clean. Furthermore, Thiels cross-overs are designed to compensate for specific drivers. As such Thiels are a time and phase coherent system, not just a 1st order cross-over in a slanted box. Thiel even goes further to adjust the cross-over so that the amplifier see a kind steady load. My description of it's sound characteristics were at the very least on the petty side. No speaker is perfect, all have their personalities. IMHO, Thiels may not excell in any particular area, but, at the same time they don't fail terribly in any particular area. All in all, dollar for dollar, they IMHO are as close to perfect as anything else out there. I not looking for a fix. I'm looking for a suitable amplifier.
Stevecham, I'm sure the Krell would be outstanding, but, unfortunately it's well beyond my budget
Well, with in your bugget I would suggest an Adcom 5800 series, or a a Bryston 4B, both are very musical and can be found used/new for a good price. Sorry about the previous, I guess I misunderstood what you were actually seeking, all be it, my buddy Bill has the same speaker as you do, and he is driving them with a 50wpc VTL tube amp. They sound nice but do not have the slam I prefer for such a large speaker.
Unsound - Good comments on the 3.5's. I am using a Krell KAV-2250 w/VTL 5.5 pre with my 3.5's. (I also alternate them with B&W's.) The KAV has the power you want and you can get one used right now for under 2k. Good luck.
Alpha 03, no need to appologize. I appreciate your input. As for your friends using 50 watt VTL's. Well, Jim Thiel told me personally that he suggested doubling the typical power recommendations when using tubes with these speakers. That would mean a minimum of 100 tube watts. Thiel did seem to like the VTL amps. I believe the equalizer used with these speakers puts considerable demands on the amplifier used. Therefore I suggest as much power as possible. IMHO 200 to 500 watts would be in order.