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Elekit-8500 Tube rolling.

Hi,

I'm planning on building the Elekit-8500 tube preamp. (new to tubes)
In my current system (Laptop-Qobuz-USB-Topping D90SE-Rotel RC-971-Rotel RB980BX-Cabasse Murano)
the topping D90SE and my cabasse murano's are too articulate (harsh would be an overstatement) on the highs (primarily the topping dac) and want to smooth it out with the elekit-8500.
What tube would smooth out the top end and bring out the best of the elekit when tube rolling?
ThX
 
Welcome aboard! Have you checked out the vkmusic.ca website? A 12AT7 isn't really the right tube. The 8500 is designed for a 12AU7/ECC82. Sometimes they are supplied with a 5965A. There's also an Elekit forum here: https://www.diyaudio.com/community/forums/elekit.134/ Since the forum software update some things can be a bit hard to find.

https://www.vkmusic.ca/TU-8500.htm
Thank you very much for the massive info!
I cannot seem to pin down what tubes I would order with the elekit 8500...
A high quality one but with adding warmth to my trebles.
Less analytical on the highs with all the yummy goodness of the tube.
As a noob and knowing that the proof is in the eating i'm trying to rely on
someone who has some knowledge about tubes.
Thank you for narrowing it down to a 12AU7/ECC82.
Now my search is on to find that tube.
Balanced tubes are for balanced applications (with XLR)?
Any tips still welcome.
 
It depends who you order the TU-8500 from what your tube options will be. I'd say build it and break it in with whatever tubes ship with it. Don't go crazy hunting down pricey NOS tubes right away.

Tube preferences don't travel well from one amp to another. There are just too many variables. A tube that sounds good in say amp A, with whatever your terms of reference are, might not be your favourite in amp B.

I've heard the TU-8500 with the previously mentioned 5965A tubes. It sounded pretty good and they're only about $5 each. A couple of ancient used and abused Telefunken ECC82s had that magic midrange/softish treble thing going on if that's what floats your boat. Me, not so much. I prefer a more neutral sound with good pace and drive.

Balanced tubes in this instance likely means the two sections inside a dual triode closely match.

Do you have much DIY audio experience? If it's only a line stage you need (the TU-8500 and a SS phono section) maybe a line stage-only project might be better for you. As always it comes down to budget too.

S.
 
Hi,

I'm planning on building the Elekit-8500 tube preamp. (new to tubes)
In my current system (Laptop-Qobuz-USB-Topping D90SE-Rotel RC-971-Rotel RB980BX-Cabasse Murano)
the topping D90SE and my cabasse murano's are too articulate (harsh would be an overstatement) on the highs (primarily the topping dac) and want to smooth it out with the elekit-8500.
What tube would smooth out the top end and bring out the best of the elekit when tube rolling?

I wouldn't rely on tube rolling to tame your speakers. Just get better/different speakers. Just sayin'. :)

jeff
 
It depends who you order the TU-8500 from what your tube options will be. I'd say build it and break it in with whatever tubes ship with it. Don't go crazy hunting down pricey NOS tubes right away.

Tube preferences don't travel well from one amp to another. There are just too many variables. A tube that sounds good in say amp A, with whatever your terms of reference are, might not be your favourite in amp B.

I've heard the TU-8500 with the previously mentioned 5965A tubes. It sounded pretty good and they're only about $5 each. A couple of ancient used and abused Telefunken ECC82s had that magic midrange/softish treble thing going on if that's what floats your boat. Me, not so much. I prefer a more neutral sound with good pace and drive.

Balanced tubes in this instance likely means the two sections inside a dual triode closely match.

Do you have much DIY audio experience? If it's only a line stage you need (the TU-8500 and a SS phono section) maybe a line stage-only project might be better for you. As always it comes down to budget too.

S.
I'll order the elekit here : https://www.jukebox-revival.eu/elekit-tu-8500-voorversterker-bouwpakket.html
Stock tubes are 2 x 12AU7 (ECC82 from JJ). No extra options except 200€ extra for a pre-builed.
I'll wait and see how the stock tubes perform and then I'll have my first reference point to compare.
I have zero experience in DIY audio but I am verry handy, have been an electrician for 12 years in the past, and have done some soldering in my life.
My older brother who works at Siemens has a high degree in electronics and he will teach me (again) how to solder and what to watch when building.
I really need a new preamp as the best/most expensive part of my system are my speakers (and I want to let them sing!) and when asking on many cabasse forums, everyone points to the Rotel preamp as being my weakest link and cause "harshness" in my highs.
The topping D90SE being verry transparant emphasises that harshness more/extra.
When I use the preamp built in the Topping D90SE I have a slightly less harshness but overall sound image/quality drops, less body.
I'vs been looking at Schiit saga+, ifi Itube2. The freya would be too expensive. Budget 500-650.
I think the elekit 8500 will outperform those, so I decided to go for the Elekit-8500.
In my search for tubes the last days I did come across some good tubes to put on my list eg the telefunken ecc82 60's smooth plate (as you mentioned) or a siemens ecc82 60's. Valvo 12au7/ecc82 long plate o-getter is also on my watchlist.
Ebay germany has everything.
Again, thank you for the assistance.
 
Last edited:
Rushed assembly and poor soldering are the two most common causes of DIY failure. I'll PM you later today with suggestions of possible improvements from my time with a 8500.

S.
That would be verry nice.
I read about upgrading some capacitors.
If I could find parts fast I would probably do some upgrades but could you point out why for each upgrade?
I'll be ordering next week and sunday i'll visit my brother for a crash-course soldering and pick up a finepoint Weller soldering machine and all that comes with it.
Thank you.
 
You have received good advise so far: don't expect tube rolling to mitigate perceived weaknesses in your current setup.

Before you purchase another preamp, I would investigate the capabilities of your Topping D90SE DAC. According to the marketing documents, your DAC can also be used as a preamp.

Doubles as a preamp

Use the D90SE in “DAC + Preamplifier” mode and connect a power amplifier or monitor speakers. Control the output volume on the front panel or with the remote control.

I would definitely try this before buying something else. If the perceived problems are the preamp and you already have that capability with your current equipment, it seems like a "no brainer' to try it. Your amp can only accept an input signal of 1Vrms according to he manual and the DAC has a 2Vrms output so there is technical issue between the DAC as a preamp and your amp.
 
You have received good advise so far: don't expect tube rolling to mitigate perceived weaknesses in your current setup.

Before you purchase another preamp, I would investigate the capabilities of your Topping D90SE DAC. According to the marketing documents, your DAC can also be used as a preamp.

Doubles as a preamp

Use the D90SE in “DAC + Preamplifier” mode and connect a power amplifier or monitor speakers. Control the output volume on the front panel or with the remote control.

I would definitely try this before buying something else. If the perceived problems are the preamp and you already have that capability with your current equipment, it seems like a "no brainer' to try it. Your amp can only accept an input signal of 1Vrms according to he manual and the DAC has a 2Vrms output so there is technical issue between the DAC as a preamp and your amp.
I would swap the Rotel for the Elekit 8500 to mitigate the preceived weakness, not the tube rolling.
I will see how the JJ stock tubes perform and maybe tweak to a Philips Miniwatt or valvo.
When I use the preamp, built in the Topping D90SE I have a slightly less harshness but overall sound image/quality drops, less body.

Thank you for helping.
 
Cabasse was known to be "analytical", in other words too much brightness, at leat in the 90's with the SCS series (iroise 500 for example).

The Rotel is probably not the culprit.

My 2 cts
ThX for the input.
The models from the nineties do have that and that's why they pair well with tube amps.
The Cabasse Murano is totally different in that aspect.
The problem is that the speakers are too revealing and revealing the flaws of the preamp.
And the Rotel RC-971 (all RC-970-980 series) is known for harshness (especially whith higher volumes).

Here is a great review of the Murano's sound signature:

In another dutch review the most excellent statement about these speakers is that they
are the poor man's TAD speaker(Steve also mentions that "holographic" tonality in the video posted above)

Thank you for helping.
 

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Installed the Elekit TU-8500 and the harshness, especially with loud volume, is completely gone after a day of listening.
So I'm a verry happy camper!
Upgraded 4xMundorf supreme and 2xMundorf Silver Gold Oil. Opamps follow later opa2227P or Muses01.
Heard that the muses are rather expressive in the highs so I'm gonna do more research.
Cool to hear 8500 "evolve" over time.
I'm leaving it on overnight and random listening at daytime.
Anyone have any tips on a tube power amp for this setup?

Murano's :
Watts RMS 150W
Peak Wattage 1000W
Sensitivity 87dB
Impedance 8ohm
Minimum impedance 3.4 ohm