The assembled boards have arrived. Looking very good. I will setup a test rig to verify they work before shipping.
I will also need to make a quick start diagram showing how to connect everything and how the power switch and the tube bypass switch works. Plus details of how to use this to control the startup logic of an external amplifier for graceful power on and off.
I will also need to make a quick start diagram showing how to connect everything and how the power switch and the tube bypass switch works. Plus details of how to use this to control the startup logic of an external amplifier for graceful power on and off.
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Hi Folks,
This is the QuickStart instruction sheet - basically the I/O schematic showing all connections to the HyperSET. The connector jacks are labeled and I have a red colored note for each one. Some are optional, for example, the external volume pot. It’s preconfigured for pass through and two SMT 0R jumpers need to be removed of using external volume pot. The amp logic control outputs are also optional. The logic is enabled after about 15 seconds to allow the tubes to warm up and for the B+ 90v supply to stabilize. The tube bypass is also optional if you always want to run in tube mode. The 6.3v output is optional and good for an external LED power on indicator.
This is the QuickStart instruction sheet - basically the I/O schematic showing all connections to the HyperSET. The connector jacks are labeled and I have a red colored note for each one. Some are optional, for example, the external volume pot. It’s preconfigured for pass through and two SMT 0R jumpers need to be removed of using external volume pot. The amp logic control outputs are also optional. The logic is enabled after about 15 seconds to allow the tubes to warm up and for the B+ 90v supply to stabilize. The tube bypass is also optional if you always want to run in tube mode. The 6.3v output is optional and good for an external LED power on indicator.
I made the connectors and testing the first one with some music and it sounds great. Don’t forget to change the gain on DIP switches from the default All ON position to desired value. 0dB is All Off, 6dB is 1=4=ON, 14dB is 2=5=ON, 20dB is 3=6=ON.
I have installed the 6N1P tubes in this case. I’ll leave it on overnight to burn in.
I have installed the 6N1P tubes in this case. I’ll leave it on overnight to burn in.
Overnight burn in was successful. Still working and sounding great. I will test all boards with tubes that will ship out. In the meantime, please order Molex KK 2 and 3 pin connector shells and crimp pins. You need a lot of them. Part numbers in the QuickStart schematic sheet above.
Hi Folks,
I have fully tested all boards with matched pairs of 6N1P tubes and prepped ready for delivery. Testing includes listening to audio output on balanced out in addition to sing or ended out. My shipment of Molex KK 2 and 3 pin connectors just arrived so I am going to include a full set of connector shells and crimp pins so you can be up and running right away. That’s 6x 2pin and 6x 3pin and 30 crimp pins (a $7 value in connectors).
I have also modified a board to have an external volume pot. This requires removing R101/103 using a soldering iron and hot solder blob. Then install an 8pin MicroMatch connector jack (female). You will need a male to male 8 pin MicroMatch cable assembly. The included volume pot helper board accepts most 6pin Alps/Bourns RK09 volume pots. Recommended value is 10k and part RK09L12D0A1T.
Here the 0R resistors near J142 have bee removed:
The 8pin Micromatch connector jack installed:
The volume control works smoothly and scratch free. Very nice and simple. I did find one minor issue. It appear the helper PCB has the rotation sense mixed up. To fix this install the pot on the opposite side of the indicated silk screen to flip the rotation. This will make the usual CCW low volume and CW high volume.
8pin IDC ribbon cable with connectors installed:
I did not have exact pot so used one I had on hand so fit is not correct:
Volume knob feature works well and allows this board to be used as a preamp to a power amp. Note that SE and Balanced outputs are simultaneous independent buffered outputs and can be used at the same time. The SE output is an OPA1656 capable of high fidelity low distortion and high current output. As shown in the BTSB, the balanced output when driven by a balanced input can be as high as 53Vpp.
I have fully tested all boards with matched pairs of 6N1P tubes and prepped ready for delivery. Testing includes listening to audio output on balanced out in addition to sing or ended out. My shipment of Molex KK 2 and 3 pin connectors just arrived so I am going to include a full set of connector shells and crimp pins so you can be up and running right away. That’s 6x 2pin and 6x 3pin and 30 crimp pins (a $7 value in connectors).
I have also modified a board to have an external volume pot. This requires removing R101/103 using a soldering iron and hot solder blob. Then install an 8pin MicroMatch connector jack (female). You will need a male to male 8 pin MicroMatch cable assembly. The included volume pot helper board accepts most 6pin Alps/Bourns RK09 volume pots. Recommended value is 10k and part RK09L12D0A1T.
Here the 0R resistors near J142 have bee removed:
The 8pin Micromatch connector jack installed:
The volume control works smoothly and scratch free. Very nice and simple. I did find one minor issue. It appear the helper PCB has the rotation sense mixed up. To fix this install the pot on the opposite side of the indicated silk screen to flip the rotation. This will make the usual CCW low volume and CW high volume.
8pin IDC ribbon cable with connectors installed:
I did not have exact pot so used one I had on hand so fit is not correct:
Volume knob feature works well and allows this board to be used as a preamp to a power amp. Note that SE and Balanced outputs are simultaneous independent buffered outputs and can be used at the same time. The SE output is an OPA1656 capable of high fidelity low distortion and high current output. As shown in the BTSB, the balanced output when driven by a balanced input can be as high as 53Vpp.
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Jhofland reminded me that the pot that was spec’d is a 0deg mounted pot (meaning the legs bend 90deg and invert). Hence the CW/CCW sense of rotation will be just fine if you buy the correct part. Sorry for the mixup. 🙂
https://www.mouser.com/ProductDetail/Alps-Alpine/RK09L12D0A1T?qs=Xb8IjHhkxj4fKHKLWV8KdA==&mgh=1
https://www.mouser.com/ProductDetail/Alps-Alpine/RK09L12D0A1T?qs=Xb8IjHhkxj4fKHKLWV8KdA==&mgh=1
This is a fine sounding preamp. I love how much oomph it has to drive any amp and the volume pot is butter smooth and scratch free when changing volumes. Doing more listening and when I connected a TT and Phono-01 preamp to it as source, wow - the sound was magnificent. Something about the tube buffer and analog vinyl giving the Class D amp that extra naturalness.
That's exactly what I thought after I finished the Warp clone - it must sound great with a tube preamp.
My anticipation is already great.
My anticipation is already great.
Hi Folks,
I am ready to ship out the orders today.
Need to confirm from @elcarlissimo if he still wants the custom RTR BTSB Lites with his order.
Studley / 1 / Uk - cancelled
“D.V.” / 1 / North America - ordered
Plott / 1 / Austria - ordered
elcarlissimo / 2 / ordered - partial refund completed
vulture / 1 / USA - ordered
“M.P.” / 1 / Bulgaria - ordered
I am ready to ship out the orders today.
Need to confirm from @elcarlissimo if he still wants the custom RTR BTSB Lites with his order.
Studley / 1 / Uk - cancelled
“D.V.” / 1 / North America - ordered
Plott / 1 / Austria - ordered
elcarlissimo / 2 / ordered - partial refund completed
vulture / 1 / USA - ordered
“M.P.” / 1 / Bulgaria - ordered
I suspected that an OPA1656 can drive headphones so I had to try. I connected my Status Audio CB-1 33ohm cans. It sounds quite good - decent bass and very clear. No discernible background noise or hiss / hum. Silence when music not playing as expected. If one adds a high current buffer to this, a very nice HPA can be made. TPA6120A2 is good.
Being able to drive 33ohms means it can drive almost any impedance amp input.
Being able to drive 33ohms means it can drive almost any impedance amp input.
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Hi X,
I just wanted to check if you have already shipped because Etsy says "not shipped"
Cheers
I think these units should be arriving or have arrived to some members by now. Looking forward to hear how they sound once you have them up and running.
Measurement of HyperSET driving 2.83Vrms into 2k2ohm load (6dB gain and SS mode) gives 0.00042% THD and nice second order dominant harmonic profile:
With 6N1P tube driving same 2.83Vrms into 2k2 ohm load we get THD of 0.062% and a nice classic SET tube harmonic profile:
With 6N1P tube driving same 2.83Vrms into 2k2 ohm load we get THD of 0.062% and a nice classic SET tube harmonic profile: