captain
22-09-2008, 19:32
Croft Phantom power amp
I brought this amp off a guy who done some work for Glenn and Amar a few years back. It was a prototype called a Phantom. After buying the amp I sent it back to Croft were it had a £1000 of work done on it. I also brought off Croft a matched pair of Mazda Solid Carbon Anode 6080’s (Rebranded Bendix 6080wb the best 6080 out there) for the output valves at a £150 and a solid carbon anodes 6336 rectifier valve for a £100, again the best 6336 of this type.
This is what Croft had to say after this rebuild:
“On closing I should say that our initial instincts in creating the Phantom were correct.....(the trafo's in this model were already quite special). Some day in the future we may choose to resurrect this fascinating instrument, if we did so I expect the cost to be in the £5k region.” (I can supply a copy of email)
A few weeks back I sent the amp to EFG (London) LTD for more upgrading. They totally rebuilt the amp, all resistors and caps are now new. The quality of the work when it comes to point to point and component lay out after this re-build is mind blowing.
None of Glenn’s circuit lay out has been changed as this is a very good amp, but a couple of features have been added. You are now able to change the feedback. This is done by turning a couple of knobs at the back (one for each channel). When in the up position it is set to Glenn’s original setting by turning one way feedback is increased giving more bass and giving a warmer sound, the other way detail increases and bass comes off. This is used in Leben amps LINK (http://www.lebenhifi.com/index.html) it is not tone control and does not work like tone control, a useful feature for matching speakers that sound a bit thin. Also added on the output is a control to bring down the peak wave (If you could see it on a scope) again not tone control, will just help if you have bright speakers no other part of the frequency is affected. When turned fully off this circuit is taken fully out so you have 100% Croft.
As said all caps have been changed it now uses all Mundorf Silver oil throughout, you can see the 4 large ones on top, there are also another 4 smaller ones under them. All resistors are within 1% tolerance. The power supply now use’s Jensen screw terminal power caps along with Mundorf Tubecaps.
All tubes have had bios reset and measured the 6080 are testing at 80%, this is after nearly 3 years with daily use so will still have at least another 12 years life. The rectifier is also about the same so still a long way to go.
Power rating is 25W it is push pull on a single valve per channel. I run speakers with a sensitivity of 87db with no problems.
I have only had this amp back from EFG (London) LTD for about 5 weeks (have recipe for work), has been used for less than 50 hours, I spent around £900 this time for work and parts. This is a very high end power amp.
Selling due to unexpected car replacement.
Looking for £1200 but have been known to haggle £20 postage PayPal OK if fee paid.
http://xs131.xs.to/xs131/08380/front234.jpg
http://xs131.xs.to/xs131/08380/back1821.jpg
http://xs131.xs.to/xs131/08380/tedpower410.jpg
http://xs131.xs.to/xs131/08380/power1548.jpg
http://xs131.xs.to/xs131/08380/power2896.jpg
http://xs131.xs.to/xs131/08380/power3564.jpg
http://xs131.xs.to/xs131/08380/power4593.jpg
Below is a picture of power amp before latest up grade spot the difference.
http://xs131.xs.to/xs131/08380/croftpowerweb915.jpg
I brought this amp off a guy who done some work for Glenn and Amar a few years back. It was a prototype called a Phantom. After buying the amp I sent it back to Croft were it had a £1000 of work done on it. I also brought off Croft a matched pair of Mazda Solid Carbon Anode 6080’s (Rebranded Bendix 6080wb the best 6080 out there) for the output valves at a £150 and a solid carbon anodes 6336 rectifier valve for a £100, again the best 6336 of this type.
This is what Croft had to say after this rebuild:
“On closing I should say that our initial instincts in creating the Phantom were correct.....(the trafo's in this model were already quite special). Some day in the future we may choose to resurrect this fascinating instrument, if we did so I expect the cost to be in the £5k region.” (I can supply a copy of email)
A few weeks back I sent the amp to EFG (London) LTD for more upgrading. They totally rebuilt the amp, all resistors and caps are now new. The quality of the work when it comes to point to point and component lay out after this re-build is mind blowing.
None of Glenn’s circuit lay out has been changed as this is a very good amp, but a couple of features have been added. You are now able to change the feedback. This is done by turning a couple of knobs at the back (one for each channel). When in the up position it is set to Glenn’s original setting by turning one way feedback is increased giving more bass and giving a warmer sound, the other way detail increases and bass comes off. This is used in Leben amps LINK (http://www.lebenhifi.com/index.html) it is not tone control and does not work like tone control, a useful feature for matching speakers that sound a bit thin. Also added on the output is a control to bring down the peak wave (If you could see it on a scope) again not tone control, will just help if you have bright speakers no other part of the frequency is affected. When turned fully off this circuit is taken fully out so you have 100% Croft.
As said all caps have been changed it now uses all Mundorf Silver oil throughout, you can see the 4 large ones on top, there are also another 4 smaller ones under them. All resistors are within 1% tolerance. The power supply now use’s Jensen screw terminal power caps along with Mundorf Tubecaps.
All tubes have had bios reset and measured the 6080 are testing at 80%, this is after nearly 3 years with daily use so will still have at least another 12 years life. The rectifier is also about the same so still a long way to go.
Power rating is 25W it is push pull on a single valve per channel. I run speakers with a sensitivity of 87db with no problems.
I have only had this amp back from EFG (London) LTD for about 5 weeks (have recipe for work), has been used for less than 50 hours, I spent around £900 this time for work and parts. This is a very high end power amp.
Selling due to unexpected car replacement.
Looking for £1200 but have been known to haggle £20 postage PayPal OK if fee paid.
http://xs131.xs.to/xs131/08380/front234.jpg
http://xs131.xs.to/xs131/08380/back1821.jpg
http://xs131.xs.to/xs131/08380/tedpower410.jpg
http://xs131.xs.to/xs131/08380/power1548.jpg
http://xs131.xs.to/xs131/08380/power2896.jpg
http://xs131.xs.to/xs131/08380/power3564.jpg
http://xs131.xs.to/xs131/08380/power4593.jpg
Below is a picture of power amp before latest up grade spot the difference.
http://xs131.xs.to/xs131/08380/croftpowerweb915.jpg