For sale is a Tubelab SE-II 300B power amp with ISO (ex-Tango) Iron
I built this amp last year with the intent to build/buy high efficiency speakers. That didn't happen so it's been packed away and I'd rather have someone enjoy this great amp.
It is a premium build, no expenses spared.
The amp will come with a pair of NOS Raytheon 5842, but not 5AR4 or 300B.
If you prefer to have an integrated volume control pot, I can add that for you after the sale.
I am asking $1650 (was $1800) shipped, which is below the cost of parts.
Consider, the ISO iron costs around $1050.
IMPORTANT: The TSE is fixed bias and requires adjusting the 300B and 5842 bias with a multimeter. The 300B have test points in the rear for easy access with the amp closed. The 5842 require attaching a probe to the coupling cap. Only purchase if you have experience and are capable of handling the high voltages present in tube amps.
Detailed build info:
- ISO transformers iron -- FC-20S opt, LC-10-200DII choke, custom PT.
- WBT 0708-Ag NextGen binding posts.
- ClarityCap TC 85uF 600V Polypropylene PS cap
- Mundorf Silver, Gold & Oil 0.1uF coupling caps.
- Resistors are Takman and Kiwame MF and CF.
- Mills MRA-10 non-inductive for the high wattage resistors.
- Mogami W2546 coaxial input wiring.
- Kimber TCSS 19ga wiring.
- Chassis by Landfall Systems
B+ is around 385V, bias at 80mA.
Currently using the 5K:8R tap, there is also a 3.5K tap if you prefer that operating point.
I built this amp last year with the intent to build/buy high efficiency speakers. That didn't happen so it's been packed away and I'd rather have someone enjoy this great amp.
It is a premium build, no expenses spared.
The amp will come with a pair of NOS Raytheon 5842, but not 5AR4 or 300B.
If you prefer to have an integrated volume control pot, I can add that for you after the sale.
I am asking $1650 (was $1800) shipped, which is below the cost of parts.
Consider, the ISO iron costs around $1050.
IMPORTANT: The TSE is fixed bias and requires adjusting the 300B and 5842 bias with a multimeter. The 300B have test points in the rear for easy access with the amp closed. The 5842 require attaching a probe to the coupling cap. Only purchase if you have experience and are capable of handling the high voltages present in tube amps.
Detailed build info:
- ISO transformers iron -- FC-20S opt, LC-10-200DII choke, custom PT.
- WBT 0708-Ag NextGen binding posts.
- ClarityCap TC 85uF 600V Polypropylene PS cap
- Mundorf Silver, Gold & Oil 0.1uF coupling caps.
- Resistors are Takman and Kiwame MF and CF.
- Mills MRA-10 non-inductive for the high wattage resistors.
- Mogami W2546 coaxial input wiring.
- Kimber TCSS 19ga wiring.
- Chassis by Landfall Systems
B+ is around 385V, bias at 80mA.
Currently using the 5K:8R tap, there is also a 3.5K tap if you prefer that operating point.
Attachments
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Thanks Luke (and dtaylo3)!
Yes you can buy new. I purchased these from ISO in Japan directly, but there are a few dealers in Europe and USA.
Yes you can buy new. I purchased these from ISO in Japan directly, but there are a few dealers in Europe and USA.
Power output is per spec of a 300B SET.
I measured 8-9W before clipping.
You can get to moderate listening levels with even 87dB speakers but I think ideally for SET amps you want to run them with 95+ dB.
No experience with this, just based on what I've read
I measured 8-9W before clipping.
You can get to moderate listening levels with even 87dB speakers but I think ideally for SET amps you want to run them with 95+ dB.
No experience with this, just based on what I've read