ELEKIT TU-8200R

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Can you please tell the amps output impedance for the different headphone settings?

It's weird. Although you can set to output volume to 4 different levels (1x, 0.75x, 0.5x, 0.25x), there is a fixed serial resistor of 220 Ohms after each setting.

This is way too much for any headphones. The old studio standard was 120 Ohms for 600 Ohm phones. Using 220 Ohms will result in low volume with low impedance headphones even at the maximum level setting not to mention frequency response anomalies especially in the bass.

I would simply bypass R43 and R44 with a shortcut made of resistors pins. For higher-end open back Sennheisers, 75-100 Ohm resistors are the best. Note that the output impedance of the original TU-8200 was about 94 Ohms.

I asked Elekit a couple of months ago about this design, but they did not answer. I used an older email contact though.
 
It's weird. Although you can set to output volume to 4 different levels (1x, 0.75x, 0.5x, 0.25x), there is a fixed serial resistor of 220 Ohms after each setting.

This is way too much for any headphones. The old studio standard was 120 Ohms for 600 Ohm phones. Using 220 Ohms will result in low volume with low impedance headphones even at the maximum level setting not to mention frequency response anomalies especially in the bass.

I would simply bypass R43 and R44 with a shortcut made of resistors pins. For higher-end open back Sennheisers, 75-100 Ohm resistors are the best. Note that the output impedance of the original TU-8200 was about 94 Ohms.

I asked Elekit a couple of months ago about this design, but they did not answer. I used an older email contact though.

Hi Victor - if possible i’d be grateful if you could respond (or facilitate a response from Elekit) to this comment. I know many people use the tu8200 as a headphone amp for lower impedance headphones such as the hifiman or mrspeakers planars. It would be good to know whether Elekit believes there is something missing or flawed in paczeltf’s analysis & suggestion, or whether Elekit believes it is a good change to make for people with lower impedance headphones (eg hifiman 1000, which has flat 34 ohm impedance per these measurements The Exceptionally Pleasing HiFiMAN HE1000 Planar Magnetic Headphone Measurements | InnerFidelity)

Many thanks
 
we have just finished the Lundahl for TU-8800. Tu-8200's chassis is too compact. to install the Lundahl . Our next project is working on Tu-8200R.

Hi Victor. No sure I understand. My question was about TU-8200R (not TU-8200). However, it appears that the TU-8200 and the TU-8200R have a similar size chassis. If the TU-8200 chassis is too small for the Lundahls, then I would imagine a similar problem could exist with the TU-8200R.

I'm currently considering purchasing the TU-8200R, but I want to make sure I have an upgrade path for Lundahls in the near future, so just looking to confirm that Lundhals will be available for the TU-8200R. Thanks for your patience.
 
we are working on TU-8200R. Both TU-8200 and TU-8200R are using the same OPT.
AS I mentioned the chassis of TU-8200 is too compact. It is not much room to position the opt to prevent the interference from the R-core.

I suggest you to look at TU-8800. The Lundhal will be available in 3~4 weeks.
 
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Joined 2018
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...I know many people use the tu8200 as a headphone amp for lower impedance headphones such as the hifiman or mrspeakers planars. It would be good to know whether Elekit believes there is something missing or flawed in paczeltf’s analysis & suggestion

Well, I don't really understand how my analysis can be flawed unless the schematics in the respective manuals are incorrect for the output section, which is very unlikely.

...or whether Elekit believes it is a good change to make for people with lower impedance headphones (eg hifiman 1000, which has flat 34 ohm impedance per these measurements

It is hard to predict how a particular set of headphones will react to driving impedance that is close or even higher than the nominal load impedance.

I acquired a Focal Clear a few weeks back. If you look at various online reviews then you will see that driving these phones from OTL and other high impedance sources is not recommended due to the upper bass hump it causes.

What I can tell you is that the Clear sounds awful with the stock TU-8200 until you bypassed the parallel 180 Ohm resistors. It is not just about the bass that gets bloated, but also the treble becomes veiled and the dynamics suffer.

Unfortunately, connecting the phones directly to the speaker output has a couple of drawbacks. First, the the background noise and hum will significantly increase. Second, the risk of damaging your phones as well as your hearing is much higher. I suspect Elekit implemented these resistors for protection but it does not come without a cost.

The 8200R has adjustable output level so if you install a pair of let's say 3.3 Ohm/1W resistors instead of 220 Ohms, you should be fine with lower impedance phones. Modifying the original model is a bit more complicated and I haven't done it yet as I am not sure if I will keep these headphones.
 
R27 is too big for TU-8200R
TKS 2CP601S will do

I managed to do it with the RK27
I had to cut the board and solder some cables like in this picture

sagamiaudio-co_4952682107347-assy_5
 
Issues with TU-8200R

Please help . . . I'm stuck!

Assembling the 8200R, and I have run into some difficulty . . .

• Unit 1, side A. Am unable to find the location for R70. I have the resistor, but no place to put it.

• I have discovered that my circuit board Unit 1, side A has TWO positions marked as R64. One in the upper right hand corner, close to D6. The other is in the upper left hand corner, adjacent to Q4.

Any help with these two questions will be GREATLY appreciated!
Thanks in advance!

Chuck
 
Help with EleKit 8200R, please

Please help . . . I'm stuck!

Assembling the 8200R, and I have run into some difficulty . . .

• Unit 1, side A. Am unable to find the location for R70. I have the resistor, but no place to put it.

• I have discovered that my circuit board Unit 1, side A has TWO positions marked as R64. One in the upper right hand corner, close to D6. The other is in the upper left hand corner, adjacent to Q4.

Any help with these two questions will be GREATLY appreciated!
Thanks in advance!

Chuck
 
I finished my build awhile ago and I love this amp with headphones. I use HD650s

First, anybody on the fence deciding if they can build this, don’t hesitate. If you have a minimal of skill with a soldering iron and can read English or Japanese, you can do it. I did and that should be good enough for anyone. There is ambiguity in the instructions.

I do have a question regarding the jumper settings for the headphones. I can’t find any information on what that should be or what the effect is by changing them. I have mine in the ‘low’ setting as suggested.

Any clarity on the three settings?
 
TKD 2CP-601

R27 is too big for TU-8200R
TKS 2CP601S will do

Hi, I am trying to install the TKD 2CP-601 pot into my new TU-8200R instead of the original ALPS. I just want to inform you, that the TKD 2CP-601 is 16 mm big and the original one is 9 mm big. The distance between the first and second line of the pins is 5 mm for TKD and the module 2 expects 3 mm distance.

The only way for me how to install the TKD is to cut out the piece of PCB from the module 2. I have to warp the TKD pins to fit them to the board. The cutted board needs to be soldered to the module 2 with some wires. The TKD will be attached to the device only thanks the module 3. But I need to drill a small hole in the module 3 for the pin on the front side of the TKD. I need to consider also the fact that the cutted board will need to be moved little bit down and back 5 mm and there is the spacer.

The second option I am thinking about is to fasten the TKD to the module 3 only and join the pins of the pot directly to the module 2 with wires, without using the cutted piece. But I am not sure if I can do it correctly as there are 8 holes and the pot has 6 pins. Can someone advice me how to do it correctly?
Has anyone some advice for me please?

The last notice is about the TKD 2CP-601S. This is mechanical stepped version with 21 steps. I do not like it as a volume control, I prefer the smooth rotation of the knob. Thank you. I wish you all the best. Milan
 

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