First pic with the bigger (0.47) mundorf silver supreme I saved from the phono stage on the 8550 pre.. it didnt fit the 8900 by a smudge, the board underneath didnt let all close in. Had to swap to the Audyn Copper Max 0.1
Other upgrades include silver solders, Allen Bradley / Dale resistors and a few capacitors; Im not the builder. I did buy a wrong potentiometer (not gonna lie, I did see the messages here and saw on the manual that RK27 was the wright one, and still I wrongly double checked before asking someone to buy the upgardes for me in North America) and furutech NFC plugs that also wouldnt fit.
Am playing mostly with speakers with some good new 300B but already tested with the Senn HD800 and wow!! Also will need to test with the supposedly better quality NOS 2a3. Will need much more time with it for burn in and to further compare with my beloved DIY Kevin Gilmore CFA3 amp. However, this is 220v and the 8900 is 115v, amps are in different cities, so a side by side is really unlikely in the short term
Other upgrades include silver solders, Allen Bradley / Dale resistors and a few capacitors; Im not the builder. I did buy a wrong potentiometer (not gonna lie, I did see the messages here and saw on the manual that RK27 was the wright one, and still I wrongly double checked before asking someone to buy the upgardes for me in North America) and furutech NFC plugs that also wouldnt fit.
Am playing mostly with speakers with some good new 300B but already tested with the Senn HD800 and wow!! Also will need to test with the supposedly better quality NOS 2a3. Will need much more time with it for burn in and to further compare with my beloved DIY Kevin Gilmore CFA3 amp. However, this is 220v and the 8900 is 115v, amps are in different cities, so a side by side is really unlikely in the short term
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^ Using the WE 300B, can I ask if you are liking the sound of this decked out 8900 with 300B tube as much or more than the 8600S/Lundahl?
Or, and anticipating you will not say one over the other in that doing so may wreck the sale of remaining inventory, is it that the decked out 8900 offers a different sound, (adjustable - feedback and some higher level parts), than 8600S, not better or worse between the highest upgrade path 8900 and highest upgrade path 8600S, just different?
BTW, When I say highest level upgrade, I am excluding Silver transformers, too expensive
Or, and anticipating you will not say one over the other in that doing so may wreck the sale of remaining inventory, is it that the decked out 8900 offers a different sound, (adjustable - feedback and some higher level parts), than 8600S, not better or worse between the highest upgrade path 8900 and highest upgrade path 8600S, just different?
BTW, When I say highest level upgrade, I am excluding Silver transformers, too expensive
I assembled this TU-8900 with VCAP CuTF + AN Tantalum Resistor for my cusomer in Switzerland
I test drine TU-8900 with 2 inches Scanspeak Full range driver....
It sounds amazing...
Victor get down to IKEA and ditch that MDF for bamboo.
I've noticed there are a number of folk using 300B amps with the small shoe box size British LS3/5A speaker which you would think would not be good match due to the sensitivity but they are 15ohm and pretty easy to drive. It seems a small room marvel from the feed back online.
ps my fingers are crossed the incoming review is going to be from HR, I look forward to taking time out to read his pieces, the latest Gramophone Dreams piece in Stereophile a good example of his story telling.
I assembled this TU-8900 with VCAP CuTF + AN Tantalum Resistor for my cusomer in Switzerland
I test drine TU-8900 with 2 inches Scanspeak Full range driver....
It sounds amazing...
Thank you @vkung for the build and the awesome communication during the process!
Can't wait to try it
Hi All,
First-time poster and relatively new to this hobby. I am trying to finish my TU-8900 build and need to install the VCAP CuTF's. With the original capacitors they are not listed as being directional. Does that hold true for the VCAP CuTF's, or do I need to worry which side the red and green leads connect to? Thanks.
John
First-time poster and relatively new to this hobby. I am trying to finish my TU-8900 build and need to install the VCAP CuTF's. With the original capacitors they are not listed as being directional. Does that hold true for the VCAP CuTF's, or do I need to worry which side the red and green leads connect to? Thanks.
John
Another happy TU-8900 solderer here. I got WE300B and WE2A3, Brimar 8087 and Sylvania 12BH7, and using V-CAP CuTF for coupling capacitors with the Lundahl amorphous core.
For my listening through a pair of full-range drivers, WE2A3 + 12BH7 with NFB turned on is the sweet spot. I don't listen loud, and it's mostly guitar and piano driven music, a bit of quieter electronic music, some casual jazz, a bit of classical, and a bit of classic rock here and there.
In this amp, to me, the 2A3 lands just right with a tiny bit of emphasis on 'cleanliness' rather than presence, the 300B just slightly on the presence with a little less emphasis on cleanliness. This is, mind you, a matter of a few degrees of difference not a huge world of difference. They are very very similar.
For my tunes with my kit, the 300B+12BH7 is a bit too unrefined, 2A3+8087 is a bit too bright.
300B+8087 and 2A3+12BH7 are very similar sounds and are just about nailed in perfect in either config. The slightly tighter low-end on the 2A3 gets my nod. The 300 has a touch extra emphasis on the bass, but loses a touch of the crisp response you get from the 2a3.
The amp itself is a marvel. Swapping tubes around to play with sounds is so much fun, I had no idea. I've got the red ring once from messing with my pre, not realizing I was live, but a power off and cool down and we were good to go. I suspect I may have sent too much input voltage.
Soldering at a moderate pace took probably 10-12 hours or so and as so many people have said, Victor was on-hand at any time, even to help decide which components, help me understand some voltages, all of it.
A few other things I noticed - dead inky black noise floor, but amazing response. The sound emerges from that void with an amazing precision and crisp attack.
It is also plenty loud enough for my listening, even with 2a3 and even with nfb. These drivers are rated @87dB sensitivity and with a Node on fixed output and a preamp at unity gain I find about halfway up the volume pot is great. 3/4 is too loud. NFB off is too loud. 300b with nfs off and the amp turned up would be ludicrous for my ears.
Got probably 80 hours on the core and about 60 hours on the 2a3s, 20 hours on the 300Bs, and it is absolutely true that this is 'settling in'. I've not really believed in break-in previously, but I'm now a believer. Might be the core re-melting.
Some of the subtle harshness I thought I might have heard out of the gates has dissipated, but it's also hilariously good at showcasing all the errors I've made in making my own speakers. A bit of congestion and drop in upper vocal areas made things sound a bit congested and muffled on some voices, and I hadn't noticed it until now. I went and plugged the speakers into a solid state predecessor amp and boom.. there it is. I literally hadn't even noticed it until hearing those speakers off this amp.
By far and away, already the best amp I've ever owned. It is making me want to go pull apart my guitar amps and play around with tubes for the first time in a decade.
Thanks, Victor!
For my listening through a pair of full-range drivers, WE2A3 + 12BH7 with NFB turned on is the sweet spot. I don't listen loud, and it's mostly guitar and piano driven music, a bit of quieter electronic music, some casual jazz, a bit of classical, and a bit of classic rock here and there.
In this amp, to me, the 2A3 lands just right with a tiny bit of emphasis on 'cleanliness' rather than presence, the 300B just slightly on the presence with a little less emphasis on cleanliness. This is, mind you, a matter of a few degrees of difference not a huge world of difference. They are very very similar.
For my tunes with my kit, the 300B+12BH7 is a bit too unrefined, 2A3+8087 is a bit too bright.
300B+8087 and 2A3+12BH7 are very similar sounds and are just about nailed in perfect in either config. The slightly tighter low-end on the 2A3 gets my nod. The 300 has a touch extra emphasis on the bass, but loses a touch of the crisp response you get from the 2a3.
The amp itself is a marvel. Swapping tubes around to play with sounds is so much fun, I had no idea. I've got the red ring once from messing with my pre, not realizing I was live, but a power off and cool down and we were good to go. I suspect I may have sent too much input voltage.
Soldering at a moderate pace took probably 10-12 hours or so and as so many people have said, Victor was on-hand at any time, even to help decide which components, help me understand some voltages, all of it.
A few other things I noticed - dead inky black noise floor, but amazing response. The sound emerges from that void with an amazing precision and crisp attack.
It is also plenty loud enough for my listening, even with 2a3 and even with nfb. These drivers are rated @87dB sensitivity and with a Node on fixed output and a preamp at unity gain I find about halfway up the volume pot is great. 3/4 is too loud. NFB off is too loud. 300b with nfs off and the amp turned up would be ludicrous for my ears.
Got probably 80 hours on the core and about 60 hours on the 2a3s, 20 hours on the 300Bs, and it is absolutely true that this is 'settling in'. I've not really believed in break-in previously, but I'm now a believer. Might be the core re-melting.
Some of the subtle harshness I thought I might have heard out of the gates has dissipated, but it's also hilariously good at showcasing all the errors I've made in making my own speakers. A bit of congestion and drop in upper vocal areas made things sound a bit congested and muffled on some voices, and I hadn't noticed it until now. I went and plugged the speakers into a solid state predecessor amp and boom.. there it is. I literally hadn't even noticed it until hearing those speakers off this amp.
By far and away, already the best amp I've ever owned. It is making me want to go pull apart my guitar amps and play around with tubes for the first time in a decade.
Thanks, Victor!