Anything wrong with Treshold "T" series??

Was told by a dealer that if I was interested in a used Threshold go for a earlier "S" as opposed to latter T series as something went wrong on latter ones.Anybody know what I am talking about?Or he was talking about?
I have not listened to the T series, but own the Threshold S300 and the S550E. Both are excellent, with the latter wining out in just sheer power and room and better defined and deeper low-end.
The "T" series makes use of output devices that are no longer available from what i understand. Having owned several amps that made use of similar circuitry with the same devices and pounding on them day after day, i would not worry about this too much if you like the amp. Just pay attention and be careful like you would with any other electronic component. Sean
Sean is correct. The T series used IGBT transistors which is a cross between bipolar and MOSFET. I think Toshiba and International Rectifer used to manufacture them but not anymore.
Hi Chazzbo,
I've not heard of any problems with the T series. I could be that the dealer is a Nelson Pass design fan, and is just somewhat biased against the T, which Nelson was not involved with. Jon Solderberg of Vintage you tell you more if you have a specific question. Like Sean, I have an S350E (inbetween the S300 and S550E), and a FET 10E pre. They are excellent, and I highly recommend them. There is a very clean S300II on eBay right now for an attractive price, but I wouldn't be afraid of a T. I do think you can get more amp for the $ with an S, as they are older. Log on to Vintage and ask Jon about the amp you are looking at. Tom
Sean is correct - the Hybrid FET-bipolar output stage (IGBTs) is no longer available, though I believe the new Threshold Audio, Inc. will bring select T-series up to current spec(for a price, of course). Jon Soderberg also works on vintage Threshold amps and will also work on the T series, though that might entail swapping out the IGBTs for a traditional output stage.

In any event, the T series was terrific, particularly the T200 - I've got one myself. They are indeed built like tanks, but nothing lasts forever...

If the price is right, go for it!

The "new" Threshold Company out of Houston, TX. wants nothing to do with the older "T" series amps. I recently had a nice long phone conversation with Mr. Curtis (Thresholds current President) and either he doesn't know about Jon Soderberg or was unwilling to let me know Jon's services were available.
I can tell you that Jon Soderberg has a T-100 in his home system.
The T-100 is the model which would have the biggest draw backs for the reasons others have stated but Jon assured me that he's never received a Threshold amp that he returned because he was unable to fix it.
The reason I know all this... I've owned a T-100 since Feb of 1994 and thought technical difficulties were being experienced and began the search for a reputable repair shop.
T series has had a long solid reputation for grainfree yet detailed and powerful sound. I spent considerable time listening to one at a friends house and was always very impressed. I had been told that the T was superior to the S series, but never had a chance to compare them myself.
I will stand corrected after reading the above posts, and I will explain why. I suggested a possible bias for a Nelson Pass design as the dealer's reason to steer you away from the T series, however knowing now about the IGBT factor, I think I would stay away from a T. Reason being; I own a PS Audio Lambda II transport in perfect condition, and it sounds great except that the belt driven pulley that opens and closes the drawer broke (the pulley, not the belt), and I can't find one anywhere. The part I need is probably less than a $0.10 mfgr cost plastic piece, yet it prevents me from selling the unit, or fixing it so that it is not a pain in the ass to use. I have been in touch with Paul at PS, and any one who could even possibly help me over the past year with no luck. I ended up buying one of the Sony SACD units 3 days ago so I would not have to be the "elected disc changer", as you have to open the cd drawer with a paperclip. I still love the sound of the Lambda II through the Ultralink II, but it is a hassle and embarrassing. So the moral of this story is, when key components of a unit are no longer available, either buy what "unique parts" that could go wrong with the unit before you buy it, or do not buy it. In HiEnd, it's always a risk no matter what you do, which is why I went with the Sony SACD... but then, I bought the "L Cassette" years ago as well, and still have an ED Beta. Buy an S. Tom