Vintage Audio Research Dual 75A Tube Stereo Amplifier (Dual 51, D75, D76 Family)
Thursday, October 20th, 2022
For sale is an Audio Research Dual 75A factory upgraded from a Dual 51 Chassis. Essentially, this unit has the transformers from the Dual 51 and the boards from a Dual 75A or possibly a D76. This upgrade must have been done back in the 70s as the tubes are all US made. There are four RCA 6550 power tubes and a single GE 6550 that is part of the circuit as well. These and the rest of the driver/preamp tubes are the originals. I don’t know for sure, but if I were to guess, I believe the owner had this unit upgraded by Audio Research and used it very little when he received it back. The boards do not have a burn spot or any amount of discoloration anywhere. When I received this amplifier, it had been sitting in a closet since it had last been used decades ago. Upon examination, the unit was indeed very dirty. So dirty that I had to completely disassemble it to clean it. The end result is a very clean amplifier. The only real issues are oxidation on the transformers, the screws, and the pots on the amplifier but the chassis is nearly perfect. The cover is in nice shape as well. The faceplate does have some minor nicks and scuffs, but is nice as well. This amplifier not perfect cosmetically, but it is nearly impossible to find an amplifier from this era with all of the original USA made tubes. Moving from the cosmetics, I didn’t simply disassemble the amplifier, clean it, and then put it back together. Many parts were replaced including all of the capacitors (with the exception of the main filter caps), numerous out of spec resistors, and diodes. Additionally, I also replaced the terminal strips (that are nearly always broken) with NOS terminal strips identical to the originals. These took many hours to find. All of the parts used were top quality including CDE capacitors, Vishay CMF resistors, and UF4007 low noise diodes. All of the hard work is done. All sockets, pots, and controls were cleaned. When I got to the point I thought the amplifier was ready to use, I went through the manual and followed the steps to set up the amplifier. Everything was reasonably within spec, thankfully and this amplifier sounds excellent. It is truly something you need to hear. I did not think I’d sell this, but it is time to move it on to someone who will use and enjoy this amplifier more than I have the time to. Price is not cheap I know, but I have 20-30 hours at least into this restoration and ARC would charge a fortune for the amount of work I did. Everything I did was as clean or cleaner than the original factory work. These amplifiers are not easy to work on. Terms (Please read these). Please message me if you have any gear for sale but don’t want to deal with listing. I live in Central California and travel to LA as well as the bay area often! You do not need to live near me. This rules comes from dealing with an individual who offered an attractive trade if I delivered the speakers to him. This ended up being a tremendous waste of time. I sell mostly vintage electronics. As such, these items are old and typically out of spec from when they were new. I do my best to test these items and make sure they work before they’re sent out, but I do not guarantee or represent that they will meet the original specifications. I may not even be able to test them, in which case assume that they don’t work. However, there are times where I may miss something. If that happens, I hope that you would agree that the most efficient way to take care of an issue is if you simply message me before opening a case or doing anything else. I need an outlet for these items online, so I have no reason to send you something that doesn’t work unless I’ve noted that it doesn’t. I pack items correctly. I know what it takes to get an item to you safely. 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. 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. 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. Please message me to work this o. This item is in the category “Consumer Electronics\Vintage Electronics\Vintage Audio & Video\Vintage Amplifiers & Tube Amps”. The seller is “doublewalledbox” and is located in this country: US. This item can be shipped to United States, Canada, United Kingdom, Australia, Japan, South Korea, Indonesia, South Africa, Thailand, Bahamas, Israel, New Zealand, Singapore, Switzerland, Norway, Saudi Arabia, United Arab Emirates, Qatar, Bahrain, Malaysia, Brazil, Chile, Colombia, Panama, Jamaica, Barbados, Bangladesh, Bermuda, Brunei Darussalam, Bolivia, Ecuador, Egypt, French Guiana, Guernsey, Gibraltar, Guadeloupe, Iceland, Jersey, Jordan, Cambodia, Cayman Islands, Liechtenstein, Sri Lanka, Monaco, Macau, Martinique, Maldives, Nicaragua, Oman, Peru, Pakistan, Paraguay, Reunion, Vietnam, Kuwait, Denmark, Romania, Slovakia, Bulgaria, Czech Republic, Finland, Hungary, Latvia, Lithuania, Malta, Estonia, Greece, Portugal, Cyprus, Slovenia, Sweden, Belgium, France, Ireland, Netherlands, Poland, Spain, Italy, Germany, Austria, Republic of Croatia, Luxembourg.
- Model: Dual 75A
- Country/Region of Manufacture: United States
- Type: Tube Amplifier
- Brand: Audio Research
- Featured Refinements: Vintage Stereo Amplifier
