Threshold T-50 vs Forte 4 ?

My local dealer has a used Threshold T-50 for sale at $700. There are occaisionally Forte 4's on Agon for $500 or less. Are these two essentially the same amps? Would they be a good match for my Spica T-60 speakers and a C-J pv10a pre-amp? Is $700 a good price for the Threshold and can it be serviced if neccessary? Sorry for so many questions in one thread. I appreciate any feedback.
$700 for a T-50 is typically well below normal used street value, let alone from a dealer. Audiogon shows the average selling price of a T-50 on the net as being $932 and i would normally expect a dealer to ask about $1100 - $1200 for this amp. I saw this on a dealers website a few days ago and if i had the cash right now, it would be in MY house and not yours : )

As to how much of a difference there is between the 4 and the T, i don't know. I would suspect that the T uses slightly better matched parts and higher grade components through-out, but that is strictly a guess. You would really have to compare them side by side to see what the differences were, if there were any.

Either way, i think that either of those amps would be right at home in your system. Sean
I believe that though the wattage is the same, the t-50 puts out more current-it is a different design-In truth with spicas either amp would be sufficient, they're both muscular for their sizes. Threshold, I heard on line, is open for service and may have reopened for business-I read this in an audio-review, review. it is second hand and should be treated as such.

good luck

I agree with Cbird. One of the first things that i noticed about the Forte' line as compared to the Threshold's is that they make use of smaller power supplies. Since that is the most expensive part of the amp and Forte's cost less than Threshold models, that makes perfect sense from a marketing standpoint.

As both Cbird and i commented, either should work well within the confines of your present system. However, the T-50 should have even more dynamic headroom and give you the extra added comfort when dealing with future purchases that might not be slightly tougher loads.

Like i said, i know which one that i would buy at those prices : ) Sean

I'll not add any to Sean's posts, he's got far more equipment experience than I do. I will comment on service; however. Remember that Threshold's last designs, the T series, used IGBT transistors that are no longer available. I don't know for sure, but I'd bet that the Forte amps all used bipolar transistors (Forte was manufactured at the same time as the Threshold S series amps I have).

There is an ex-Threshold technician named Jon Soderberg in California that services Threshold equipment. I'd seen at one time that he is willing to replace the T series IGBTs with another, readily available transistor. I have no idea what that would do to the sound on the amp.
Thank you all for your responses. From what I can determine, both the Threshold and the Forte use the IGBT transistors. Both are suppose to have 8 per channel. I am concerned about the reliability of these and potential service. Macdonj, do you happen to have an email address or website for Mr. Soderberg?


I own a T 400 and have never had any troubles. I think the price of $700 is very good, especially from a dealer. I'd go in that direction.

Good luck,
I've run Forte' 4's and 6's ( both use IGBT's ) on low efficiency 2 ohm speakers and throttled them. No problems what so ever.

Just remember this: He who hesitates is lost. You better snag it before someone else does. Sean
The price of the T-50 is definitely good.

However, since it's so cheap, I'll make sure to check with him any repair/mod history. I'd be suprised he doesn't know the true value of this amp. Does it come with manual/box? Do they look beat up? Just be careful.

I own a T-200 and never have any problems.
Yes, the IGBT tranistors aren't replacable.

Threshold is definitely back in business with services of previous models as well. Check out

Hope this helps.