Vintage NOS Threshold SA-1 Mono Block Power Amplifier Pair

Description: For sale is a pair of Threshold SA-1 mono block amplifiers in new condition. I purchased these brand new in the box from the original owner. They had sat unused for over 30 years in their sealed boxes. When I received these, I decided to open the boxes and see how they sounded. Unfortunately, I was not impressed by the performance and thought the power consumption was a bit high. There was also 50mV or so of DC offset at both outputs. Nothing that would hurt anything but I found it to be unacceptable that I could not adjust it. Additionally, I noticed that the heatsinks were not uniformly warm, so I decided it was best to restore these and see what they were capable of. Below is a list of actions performed on these: -removed, cleaned, tested, and re-applied thermal paste to all 80 of the transistors with new mica insulators installed. -replaced all ~80 emitter resistors with Vishay NS non-inductive wirewound resistors ($200 cost). -replaced all 8 filter caps with EPCOS B41560A9339M000-ND 33000uf 1000V capacitors ($806 cost). These are far better quality caps than the originals were. The power consumption is now lower because there is less leakage with these. -replaced all capacitors and resistors on the driver boards using Vishay/Texas Components metal foil parts. ($812 cost). I've tested these amps and used them for less than 10 hours. They now sound incredible and the DC offset is negligible. The only issue is that they heat the room up where I placed them and given half the year is warm to very hot where I am, these do not make sense for me to keep. The rest of the set of new Threshold components are for sale in other listings if you're interested. One unit has a small imperfection on one of the faceplates that was present when I opened the box. Given the thick foam packing material, I believe it happened at the factory. Boxes and original packing materials along with all of the documentation is included. I will place the boxes into a larger box to protect the amps even further. Please let me know if you have any questions. Terms (Please read these) I will do my best to represent all major cosmetic damage to any items that I sell, but when you purchase something from me, expect minor scratches and nicks unless I've noted that the item is free of them. I pack items correctly. I know what it takes to get an item to you safely. As a result, you may see that the shipping quote shown is higher than you're accustomed to. Rest assured, I lose money on just about every item I ship when packing materials are considered, but if I don't, I will absolutely refund you the difference. You will NOT have to ask for it. I will do my best to get items out within a few days, however there are instances where that is not possible especially around holidays. Please see the handling time to know how long it may take for me to ship an item. The policies here are difficult in this regard because these vintage items in particular need to be moved and packed carefully. I do not want to damage anything by rushing. Buying the proper materials may also take time. I am not as fast as Amazon, but I guarantee I'll pack better. With this all being said, if there is any reason that you don't feel that you can leave FIVE stars in every category, please reach out to me before leaving any feedback other than positive with all five stars in every category. FOR EBAY GLOBAL SHIPPING PROGRAM CUSTOMERS:The program will not allow me to ship tubes. If you purchase an item with tubes in them, the TUBES CANNOT BE INCLUDED. I can send them to you directly, but they will not be included with your shipment. Please message me to work this o

Price: 9999 USD

Location: Hanford, California

End Time: 2024-09-22T01:27:00.000Z

Shipping Cost: N/A USD