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Yes. I got the TAP-1 sounds very nice with N8ii to use for headphone (Whitigir introduces that to me!).
KAEI introduced a smaller 3.5SE only tube amp. TAP-2.
On a AE product description the tube used in the TAP-2 is listed as "Using two American jan6418 tubes for RAYTHEON".
Maybe the TAP-1 is using the same tube?
Can’t help but to find this funny:Since my TAP-1S is disassembled, to modify the case, I took a photo of the four tubes.
They're taped, labeling down, to the bubble-wrap (Description from the AliExpress webstore - Air bag shock absorption technology: exclusive electronic tube suspension air shock absorption technology, effectively reducing the microphone effect).
So, I can't read the numbers on them.
But, they do look like photos of the Raytheon JAN 6418 tubes that are in eBay listings.
It is interesting that a lot of the small, portable, headphone amps are using NOS (New Old Stock) tubes that were designed in the 1950s & '60s - and that haven't been produced for 30 or 40 years.
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[ Photo of the inside of my KAEI TAP-1S ]
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Nice! Are you planning to install Burson V6 Vivid op-amps?Well ... I didn't end up being able to use the X-Y table, bolted to my Dremel Drill Press - since the Z-axis mechanism that holds the Dremel, isn't stable enough to hold it stationary against the lateral forces that machining aluminum would produce.
But, I was able to use the Dremel, and some Cut Off Discs, to cut out the openings in the top of my TAP-1S.
There were a few scuffs & scrapes around the openings, so I went over them with a black permanent marker.
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My modified TAP-1S -
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Nice! Are you planning to install Burson V6 Vivid op-amps?
Actually the "exclusive electronic tube suspension air shock absorption technology" is more than just bubble wrap, though most people will focus solely on that.Can’t help but to find this funny:
“exclusive electronic tube suspension air shock absorption technology” = …bubble wrap
What will they think of next
I made those measurements some time ago...I can - but first, I'm going to measure the (+) and (-) supply voltages, to see which op-amps can be used safely.
I made those measurements some time ago...
pin 4 to ground: -7.9vdc
pin 8 to ground: +7.9vdc
pin 4 to pin 8: +15.8vdc
Pretty low rail voltages.
Edit: I read back on the previous page where you mention cutting the holes... looks like maybe SS3602 op-amps are your goal(?).
Well, that's nice to know. I tried Burson V5i-D op-amps without any issues, sounded great. Of course, can't slide the boards back in due to height clearance which you already resolved. I also picked up a couple Analog Devices AD827SQ per a recommendation by our friend @WoodyLuvr, but they did not work at all. Those AD827SQ had a loud hiss. That's actually why I measured the op-amp supply rails because I could not figure out the cause of the loud hiss. Since we don't have a schematic, the only thing I could think of is that the op-amp circuit is optimized for MUSES02, though the AD827SQ should be compatible and has the same pinout.I did do a quick check with a set of the SS3602 - but they had noise / oscillation, and were getting hot to the touch. So I installed a set of OPA-1622, and they're working fine.
I made those measurements without the linear psu, so not sure if the values will change with the linear psu connected.I made those measurements some time ago...
pin 4 to ground: -7.9vdc
pin 8 to ground: +7.9vdc
pin 4 to pin 8: +15.8vdc
Pretty low rail voltages.
Actually the "exclusive electronic tube suspension air shock absorption technology" is more than just bubble wrap, though most people will focus solely on that.
Photo credit: @DBaldock9
Most people will ignore / overlook the leads from the tubes to the PCB. The normal tube leads are solid wires. They replaced those leads with very flexible wires which allows the tubes to "float" on a cushion of air (contained in bubble wrap) lessening mechanical shock and tube ringing. It's really a clever design / workaround.