This weekend I took a trip down to Wales to pick up some super cheap KEF 4 ways. The day before I was leaving the seller messages me to say she also found some old valve amps in the shed and would I be interested in them as well. She reels off the model numbers and starts saying a grand plus for each of them, probably just saw the listings on ebay. I said bit pricey for me but send some photos anyway.
When I saw the photos I knew they were something special as a hifi friend has mentioned Leak valve amps in the past so started to do a bit of research. I got in touch with Tony of this forum and he gave me some solid advice. I ended up bringing home 2 x TL/12+ mono blocks, a Stereo 60, Varislope Stereo 2 and a Through Line 3, plus the gorgeous KEFs, for £800 which I was pretty pleased about. Not bargain basement prices but this stuff doesn't come around often so figured it was worth the risk. I managed to talk her down thanks to Tonys valuable insight, mainly that the mains transformer of the Stereo 60 was not stock and so its collectible value has all but gone, as well as some valves, including the GZ37, were unusable. Mullard throughout however! Blessing and a curse, as some will need replacing, so I may have to go with Mullard to keep everything the same...tricky decisions.
I now get to begin the challenge of restoring these. Obviously all the out of spec passives have to go, I'll stick with carbon composite resistors and oil caps as per Tony's recommendation. I like the idea of leaving the original can caps in place and installing new ones on the underside of the chassis to retain the original look. I've got access to a proper tube tester so hopefully the ones that look physically fine will be good to use. The GZ37 rectifier looks shot, I may just replace with some diodes to get up and running, or just shell out for a Mullard NOS...who knows.
The monoblocks look nearly stock, a few caps changed, a few resistors burnt but all in all pretty decent. Their valves were a bit worse for wear, a few cracked, a few lost the getter, but transformers thankfully seem okay. Original green 100R resistors are there also. The same can't be said about the Stereo 60 unfortunately...The green resistor has gone, and the mains transformer has been replaced, leading to the chassis being butchered to make it fit, as well as lot of other things been messed with. Initially when I looked at it there was a label of 300-0-300 so I thought I was okay, but on further research, it seems like the 60 used a 430V transformer, not 300! So I may be all out of luck there...
I've worked on plenty of solid state amps but nothing this seriously valve, messed around with some guitar amps but this is my first proper explore into valve territory. My uneducated thinking leads me to believe that it just won't have as much power output as it would have with the stock power transformer, is this right? If thats the case then I may be able to get away with using it, if not I may have to find a replacement. I found one online that is marketed as a Mullard 5-20 stereo replacement mains transformer with seemingly the close enough specs at 410-0-410 400ma, but not cheap at around £200
There also seems to be some strange resistors mounted on top of the chassis, with terminal blocks and hot glue...can anyone explain what they are doing there?
I think I'll do one mono block first, get comfortable working with valves, I also reckon I have enough good valves to get one working. Then I'll attempt to tackle the 60, hopefully it wont be too much of a pain to get working again! With the pre amp and tuner, I'll probably get working again then stick on ebay, as I know they aren't really very well regarded units and I have no need for them, a rebuilt Bozak CMA 2DL will run pre amp duty in this system!
Heres some photos
When I saw the photos I knew they were something special as a hifi friend has mentioned Leak valve amps in the past so started to do a bit of research. I got in touch with Tony of this forum and he gave me some solid advice. I ended up bringing home 2 x TL/12+ mono blocks, a Stereo 60, Varislope Stereo 2 and a Through Line 3, plus the gorgeous KEFs, for £800 which I was pretty pleased about. Not bargain basement prices but this stuff doesn't come around often so figured it was worth the risk. I managed to talk her down thanks to Tonys valuable insight, mainly that the mains transformer of the Stereo 60 was not stock and so its collectible value has all but gone, as well as some valves, including the GZ37, were unusable. Mullard throughout however! Blessing and a curse, as some will need replacing, so I may have to go with Mullard to keep everything the same...tricky decisions.
I now get to begin the challenge of restoring these. Obviously all the out of spec passives have to go, I'll stick with carbon composite resistors and oil caps as per Tony's recommendation. I like the idea of leaving the original can caps in place and installing new ones on the underside of the chassis to retain the original look. I've got access to a proper tube tester so hopefully the ones that look physically fine will be good to use. The GZ37 rectifier looks shot, I may just replace with some diodes to get up and running, or just shell out for a Mullard NOS...who knows.
The monoblocks look nearly stock, a few caps changed, a few resistors burnt but all in all pretty decent. Their valves were a bit worse for wear, a few cracked, a few lost the getter, but transformers thankfully seem okay. Original green 100R resistors are there also. The same can't be said about the Stereo 60 unfortunately...The green resistor has gone, and the mains transformer has been replaced, leading to the chassis being butchered to make it fit, as well as lot of other things been messed with. Initially when I looked at it there was a label of 300-0-300 so I thought I was okay, but on further research, it seems like the 60 used a 430V transformer, not 300! So I may be all out of luck there...
I've worked on plenty of solid state amps but nothing this seriously valve, messed around with some guitar amps but this is my first proper explore into valve territory. My uneducated thinking leads me to believe that it just won't have as much power output as it would have with the stock power transformer, is this right? If thats the case then I may be able to get away with using it, if not I may have to find a replacement. I found one online that is marketed as a Mullard 5-20 stereo replacement mains transformer with seemingly the close enough specs at 410-0-410 400ma, but not cheap at around £200
There also seems to be some strange resistors mounted on top of the chassis, with terminal blocks and hot glue...can anyone explain what they are doing there?
I think I'll do one mono block first, get comfortable working with valves, I also reckon I have enough good valves to get one working. Then I'll attempt to tackle the 60, hopefully it wont be too much of a pain to get working again! With the pre amp and tuner, I'll probably get working again then stick on ebay, as I know they aren't really very well regarded units and I have no need for them, a rebuilt Bozak CMA 2DL will run pre amp duty in this system!
Heres some photos
