Hi All - i'm interested in thoughts from those who have paired with the TU-8550 with the 8600 or 8900. What differences/benefits did you notice over just using the integrated on its own? I'm not a vinyl guy so the phono stage wouldn't get much use but i'm interested if there is an appreciable improvement in the sound, and looking for an excuse for another build.
For me the TU-8550 provides added flexibility when using multiple inputs. On the other hand, sound quality is very subjective. Personally I think the TU-8550 is very transparent. YMMV depending on configuration (caps, tube complement, etc.). I use mine with my TU-8900 with 2A3 tubes and it is my favorite listening experience, and I've got three other Elekit amps, a PrimaLuna amp, and a Pioneer SX-950, all of which I use on a rotating basis.
I just completed my build of the TU-8550. Very sweet kit to assemble and sounds great. I was, however, sadden to discover that the case footprint does not match my TU-8600S. The TU-8550 is about 30mm narrower. To me it looks odd setting under the 8600. The power switch and knobs are a different style as well. I have begun investigating make a complementary faceplate. If anyone has information about the power switch make & model and or knobs for TU-8600S, I'd appreciate hearing from you. I am trying to decide between designing a new chassis or add extensions to the sides of the existing TU-8550 chassis.
First test of my just built Elekit 8900. Initial relief that everything works as expected is soon replaced by a strong astonishment over its sound! It’s incredible. My Luxman LX380 is used as a preamp with the Elekit. The music is transparent (audio lingo that previously sounded, well, mostly like talk…). Bas is much stronger so I had to adjust my Avantgarde by lowering the bas. It’s quick and airy. Lundahl transformers, vintage RTF ECC82, NOS Sylvania spring top 2A3 from 1945.
And apparently there is upgrades to be made…
Now I need to check if I have it set up with or without feedback!😳😊
Ah frustrating. I’m planning on going down the same route, thanks for sharing.
Most importantly does it sounded better than the 8600s as a standalone integrated?
I truly love these kits and look forward to building the next one, but, for now I've decided to take the cheaper route and design and fabricate a new chassis and faceplate. In fact I should be getting v1 back from SendCutSend next week. Here's a look at the bottom half of the chassis. I'm adding the TU-8550 components to the model for fun.
Yes. To the point. To me the TU-8550 is transparent. If you're looking to improve the sound of the TU-8600 you're asking a lot, so, for me the addition of a balance control and multiple inputs is worth the cost. Plus, building these kits is fun and easy. I just wish they hadn't the same chassis width.
We'll all be interested in seeing the progress on this project. I might have gone the other way and put the TU-8600 in a new chassis, but either way it should be fun.
I reasoned that the TU-8550 chassis is a lot simpler to build with less parts than the TU-8600. Also I'm not a fan of the power button on the TU-8550. Building a new chassis allows me to change out the push button for toggle switch. Not to mention I broke the stem on the 8550 switch trying to force the poorly formed connecting rod to it. Causing me to design and 3d print a support for the connecting rod.
The chassis is schedule to be here on Friday (which is a 9 day turn around). The two halves of the chassis cost $125 including tax and shipping. SendCutSend does not offer tapping on A36 cold rolled steel less than 0.059" / 1.5mm. I plan to hand tap this time around. Not to mention tapping adds considerable cost. Next version will be rivet nut ready.
The faceplate has become a little more challenging to match the finish. I like Front Panel Express for their design software and quick quote, however, they have drop Brushed Aluminium from their list of materials. At present their cost for my anodized natural aluminium faceplate is about $75 excluding tax and shipping.
Of course these prices can be reduced with volume purchases as low as 10 units.
One of the few things I can fault Elekit with is the quality of the chassis. It's adequate but not top tier. And I agree, the switch mechanism leaves a lot to be desired. If I had some motivation I'd design a new aluminum case with provision for a front mounted power switch. When I built my TU-8850 I thought the feet were messed up because the chassis wouldn't sit straight. Then I realized the whole chassis was bent. I had to take everything apart and carefully bend it back so it would sit flat.
I've got to hand it to the folks over at SendCutSend. The chassis arrived yesterday and it is very well made and packaged.
All the holes line up. Now I got to get my hands on a 3mm and 4mm tap. And some black spray paint.
I also have the led holder (hole next to the power switch) to design a print.
All the holes line up. Now I got to get my hands on a 3mm and 4mm tap. And some black spray paint.
I also have the led holder (hole next to the power switch) to design a print.
I got the holes tapped... Not a big fan. Version 2 will definitely have revit nuts. I'll have to increase the chassis height by a few millimeters to accommodate the larger revit nut holes along the bottom edge. Here's a first look at two systems stacked. Albeit without the new TU-8550 faceplate. I've got to call Front Panel Express tomorrow and ask about Brushed Aluminium Stock. For some reason they stopped offering it a few years back.
Couple of things I missed up. The chassis is 4mm to wide and the feet need to be moved in broad 5mm each. The faceplate mounting holes are 3mm to wide compared to the TU-8600S.
I have the Power On LED holder in place. My first thought for powering the LED was to attach a 120vac to 12vdc buck converter to the power PCB. My thinking for this was not to introduce any new circuitry to the main PCB. But, it does seem like a lot of hardware for such a simple task. Any recommendations for how to add this extra power indicator lamp are appreciated.
P.S. Here's what the pair looked like before.
Couple of things I missed up. The chassis is 4mm to wide and the feet need to be moved in broad 5mm each. The faceplate mounting holes are 3mm to wide compared to the TU-8600S.
I have the Power On LED holder in place. My first thought for powering the LED was to attach a 120vac to 12vdc buck converter to the power PCB. My thinking for this was not to introduce any new circuitry to the main PCB. But, it does seem like a lot of hardware for such a simple task. Any recommendations for how to add this extra power indicator lamp are appreciated.
P.S. Here's what the pair looked like before.
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Forward progress today. I've installed and wired the Switch, LED and Buck Converter. In the next iteration of the chassis I'll move the transformer back 5mm closer to the Power PCB, for more clearance around the power switch. I've also made a $78 commitment and ordered a faceplate. The last email from Front Panel Express said my design passed technical inspection and is in production.
Did they have brushed aluminum to match? Also, why did you install a power LED when you have LED's at the volume knob?
Thanks for taking interest in my project.
Front Panel Express does not offer a Brushed Aluminum finish anymore. There was no explanation given. I am, however, now convinced that what I thought was brush strokes on the original finish are nothing more than the natural grain of the production process, which has been clear anodized. At least that's what I'm hoping for. I'll know for sure in a week and I'll report here.
My thinking on the power LED indicator was not to introduce any new circuitry to the business side of this preamp. The buck converter is a $8 part, so not a huge expense.
I'm reconsidering my thinking about the new led power source. The buck converter is just to clunky, so I've been studying the schematic. It seems to me that I could remove LED302 and short it's thru hole connection. Remove LED301 and install header pins for new blue LED cable. May need to adjust R307 and R306. Right now I'm using 47k resistor and blue LED matches the brightness of the TU-8600S pretty close.