I have a similar problem - speakers - and in my case a very large dead room. Though more sensitive than your speakers mine find the KX2
just a little shy of driving the speakers with full scale orchestral music at a comfortably loud volume. Smaller scale music is absolutely
great. I also have one of Bonsai's Ovation amps - an early version of the original Nx...this amp is quite capable of driving the speakers and room to far higher volume than I would normally use. [I also have Bonsai's line preamp...superb, totally superb]
If you decide to go for the NX2 I am absolutely sure that you will be delighted with the result.
just a little shy of driving the speakers with full scale orchestral music at a comfortably loud volume. Smaller scale music is absolutely
great. I also have one of Bonsai's Ovation amps - an early version of the original Nx...this amp is quite capable of driving the speakers and room to far higher volume than I would normally use. [I also have Bonsai's line preamp...superb, totally superb]
If you decide to go for the NX2 I am absolutely sure that you will be delighted with the result.
Hello,
I am thinking of building this amp. I have a 18v 400va transformer. I understand that it is recommended to run 22v. I will run it in a small space so loudness is not an issue. Do you think this is a major limiting factor?
Tia
I am thinking of building this amp. I have a 18v 400va transformer. I understand that it is recommended to run 22v. I will run it in a small space so loudness is not an issue. Do you think this is a major limiting factor?
Tia
Hi, you need 2x 18V so you can get say +25 and -25 V DC out after smoothing and rectification. Any dual rail voltage between 25 to 30 will work well.
I usually recommend the Modushop Mini Dissipante 4U x 300mm deep chassis. If I am reading your post correctly it is only 112mm high so you will have difficulty in fitting the amplifier boards.
IF you look at the bottom of the first post in this thread there is a zip file called 'Hifisonix Universal Chassis' - the dimensions and drillings are in there. You can just send the .fpd files directly to Gianluca at Modushop and he will pre-drill the heatsinks and rear panel for a small fee. I highly recommend this approach if you can.
BTW, this chassis will also take the 100W nx-Amplifier and the new (still coming) nx2-Amplifier (also 100W).
Any questions, let me know.
IF you look at the bottom of the first post in this thread there is a zip file called 'Hifisonix Universal Chassis' - the dimensions and drillings are in there. You can just send the .fpd files directly to Gianluca at Modushop and he will pre-drill the heatsinks and rear panel for a small fee. I highly recommend this approach if you can.
BTW, this chassis will also take the 100W nx-Amplifier and the new (still coming) nx2-Amplifier (also 100W).
Any questions, let me know.
Hello Andrew,
Thank you for sharing such a great project with the community. Work in progress, waiting for few parts.
I have few pairs Sanken 2SC3519A/2SA1386A and 2SC3263/2SA1294. Is it ok to use them, which is recommended?
Vbe and hFE are measured, other info is from the datasheet
2SC3519A
Vbe 0.542 - 0.549
hFE 139-166
Vce 180V
Ic 15A
Pc 130W
Cob 250pf
fT 50MHz
2SA1386A
Vbe 0.529 - 0.537
hFE 132-159
Vce 180V
Ic 15A
Pc 130W
Cob 250pf
fT 40MHz
-----------------------
2SC3263
0.537 0.542
hFE 103-111
Vce 230V
Ic 15A
Pc 130W
Cob 250pf
fT 60MHz
2SA1294
0.527 - 0.536
hFE 102-113
Vce 230V
Ic 15A
Pc 130W
Cob 500pf
fT 35MHz
Also I have issue finding insulated copper wire 1.2-1.25mm for the output coil.
Is it ok to use 1.15mm (1mm2 stripped electric household wire) diameter with heat shrink tubing 2mm?
For TO-126 transistor I will used KEC
Q10 KTC2800 KSC2690A
Q11 KTA1700 KSA1220A
Q4 KTC3503 KSC3503
Q3 KTA1381 KSA1381
Thank you for sharing such a great project with the community. Work in progress, waiting for few parts.
I have few pairs Sanken 2SC3519A/2SA1386A and 2SC3263/2SA1294. Is it ok to use them, which is recommended?
Vbe and hFE are measured, other info is from the datasheet
2SC3519A
Vbe 0.542 - 0.549
hFE 139-166
Vce 180V
Ic 15A
Pc 130W
Cob 250pf
fT 50MHz
2SA1386A
Vbe 0.529 - 0.537
hFE 132-159
Vce 180V
Ic 15A
Pc 130W
Cob 250pf
fT 40MHz
-----------------------
2SC3263
0.537 0.542
hFE 103-111
Vce 230V
Ic 15A
Pc 130W
Cob 250pf
fT 60MHz
2SA1294
0.527 - 0.536
hFE 102-113
Vce 230V
Ic 15A
Pc 130W
Cob 500pf
fT 35MHz
Also I have issue finding insulated copper wire 1.2-1.25mm for the output coil.
Is it ok to use 1.15mm (1mm2 stripped electric household wire) diameter with heat shrink tubing 2mm?
For TO-126 transistor I will used KEC
Q10 KTC2800 KSC2690A
Q11 KTA1700 KSA1220A
Q4 KTC3503 KSC3503
Q3 KTA1381 KSA1381
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Hello DRN,
apologies for the late reply, I have had no internet for 2 weeks.
Those devices you want to use for the output look ok - you should be able to use them.
Your proposal to use stripped household wire for the coil is okay. For the output coil, the most important thing is that the inductor measures 0.8uH or higher. Can you measure the inductor?
apologies for the late reply, I have had no internet for 2 weeks.
Those devices you want to use for the output look ok - you should be able to use them.
Your proposal to use stripped household wire for the coil is okay. For the output coil, the most important thing is that the inductor measures 0.8uH or higher. Can you measure the inductor?