This is an amplifier I made a long time ago
But due to the parts at that time not meeting the specifications. I made it around 2012.
But the test results were very poor. So I have been improving it.
I have recently obtained some very good transistors. The test results in the new version make me feel very good.
It has almost the same performance indicators as the machines produced by QUAD's original factory.
So I'm going to take the time to assemble it and listen to it myself. I will update the assembly steps.
of course. I am also an amateur businessman. I will provide it to others. But the condition is.
This product needs my approval. Otherwise, I will throw it away. For example, the QUAD707-2012 version. I have never had anyone sell it before.
But due to the parts at that time not meeting the specifications. I made it around 2012.
But the test results were very poor. So I have been improving it.
I have recently obtained some very good transistors. The test results in the new version make me feel very good.
It has almost the same performance indicators as the machines produced by QUAD's original factory.
So I'm going to take the time to assemble it and listen to it myself. I will update the assembly steps.
of course. I am also an amateur businessman. I will provide it to others. But the condition is.
This product needs my approval. Otherwise, I will throw it away. For example, the QUAD707-2012 version. I have never had anyone sell it before.
Attachments
This is the chassis I purchased on Taobao
About 38 dollars
I use software to draw a fixed installation hole for the power tube.
I don't know how to make holes myself. That screw hole is too troublesome.
I will have the chassis manufacturer drill the screw holes.
About 38 dollars
I use software to draw a fixed installation hole for the power tube.
I don't know how to make holes myself. That screw hole is too troublesome.
I will have the chassis manufacturer drill the screw holes.
Attachments
Chassis punch will easily make holes larger than 12mm (0.5 inch) after drilling a small hole.
https://www.harborfreight.com/knockout-punch-kit-10-piece-60575.html
https://www.harborfreight.com/knockout-punch-kit-10-piece-60575.html
I purchased a 2.6MM drill bit. I have a fixed drilling platform. I made a hole.
Then use the M3 tapping head manually. But it takes too much effort. Then I used a 2.7MM drill bit.
be prone to.
But the screws cannot be tightened. I thought for a moment. Still spent an extra $4. Let the seller of the chassis help me with these tasks.
Attachments
Compared to QUAD405, QUAD707 has a very significant change. Mainly for improvement.
Measure QUAD707 SR=25V/US using an oscilloscope.
QUAD405 SR=4V/US. Although it does not represent good or bad. But it is obvious that the changes in QUAD707 are significant.
Additionally, QUAD707 is high-frequency. Low frequency. The attenuation rate is smaller. It retains its beautiful sound while also preserving it.
It has significantly improved performance. It was born around 1995.
Measure QUAD707 SR=25V/US using an oscilloscope.
QUAD405 SR=4V/US. Although it does not represent good or bad. But it is obvious that the changes in QUAD707 are significant.
Additionally, QUAD707 is high-frequency. Low frequency. The attenuation rate is smaller. It retains its beautiful sound while also preserving it.
It has significantly improved performance. It was born around 1995.
