Elekit TU-8600R 300B SET amp/headphone amp

[Jon L]

Made an impulse buy for this intriguing 300B SET, which is turning out to have great resolution and bass definition for a 300B SET, through speakers, headphone amp, AND driving electrostats via Stax transformer!

https://www.stereophile.com/content/gramophone-dreams-27-elekit-tu-8600r-amplifier-kit

1126191526a by drjlo2, on Flickr

[Tachikoma]

How does it compare to your direct drive amps? and do you have the Lundahl transformers in this unit?

[Jon L]

23 hours ago, Tachikoma said:

How does it compare to your direct drive amps? and do you have the Lundahl transformers in this unit?

Don't have any DD amps on hand to directly compare, but I bought the Elekit to triple as speaker amp, stat amp via transformer, and to power Abyss 1266 Phi TC planars.  

And it does have Lundahl's and Mundorf silver/gold/oil caps. (below photo from Stereophile)

ElekitTx by drjlo2, on Flickr

Edited December 5, 2019 by Jon L

[Torpedo]

Planars? OMG those are usually hard to drive bitches. Being headphones the Elekit should be more than enough. What about the speakers, what are yours? For Stax the bottleneck is the transformer, so I can imagine the results. I wish I had 98db/w/m speakers or higher sensitivity to try a 300B SET.

[Jon L]

My speakers are custom jobs at measured honest 95dB/7 Ohm, with bass offloaded to another amp, so even 3 watts are usually enough.  But just for fun, I have the infamous Klipsch RP-600M on their way.  It's usually a bad idea to rely too much on reviewers, but at the Klipsch's reasonable price, what the heck...

Herb Reichert of Stereophile:

"The EleKit and Klipsch RP-600Ms together cost only $2600, but musically and sonically satisfied me as much as if they cost $26,000. To my complete surprise, this pairing exceeded the Orangutan+SIT-3 combo in apparent speed, tightness of bass, and boogie PRaT fun factor. The TU-8600R powering the RP-600Ms, sourced by the Chord Qutest DAC ($1895), created a complete under-$6k system, including cables and stands, that I'd be hard-pressed to improve on."
 

[Torpedo]

I read the review. Please, by all means let us know how do those Klipsch perform. The world needs more efficient and sensitive devices. And people, probably.

[Jon L]

Huh... I guess this THX technology business is not ALL hype after all.

In my Holiday shopping binge, I couldn't resist buying the SMSL SP200 THX tech amp for measly $260 +tax.  Boy, cheap headphone amps have come a long way since I was last into dynamic headphones years ago... Sennheiser HD600 with ALO cable sounding mighty fine burning in the amp.

 

 

[purk]

Better than the Gilmore Lite MK2?  Love the look  of the upgrade cable!

[Jon L]

Would love to try Gilmore Lite Mk2 and compare, but year-end shopping has lightened my pockets, especially the Abyss.

I WILL say the little SMSL SP200 is driving the Abyss 1266 Phi TC with authority and clarity.  

AbyssSMSL by drjlo2, on Flickr

[Rossliew]

On 12/5/2019 at 11:37 AM, Jon L said:

Don't have any DD amps on hand to directly compare, but I bought the Elekit to triple as speaker amp, stat amp via transformer, and to power Abyss 1266 Phi TC planars.  

And it does have Lundahl's and Mundorf silver/gold/oil caps. (below photo from Stereophile)

ElekitTx by drjlo2, on Flickr

 

Do you drive your planars directly off the amp's speaker taps or via the headphone jack?

 

 

[Jon L]

Off the speaker taps.  

The front headphone jack has 4 jumper settings for difference impedance 'phones. Normal headphones like Sennheiser HD600, 32 Ohm IEM's sound fine on front headphone jack, but no setting is optimal for Abyss, not able to deliver enough power.  Off the speaker taps, there is way more than enough power.   

[Rossliew]

40 minutes ago, Jon L said:

Off the speaker taps.  

The front headphone jack has 4 jumper settings for difference impedance 'phones. Normal headphones like Sennheiser HD600, 32 Ohm IEM's sound fine on front headphone jack, but no setting is optimal for Abyss, not able to deliver enough power.  Off the speaker taps, there is way more than enough power.   

Thanks. Do you use any resistors across the speaker taps? 

[Jon L]

Nope, no need for Abyss but may need the resistor if you have a lot more sensitive planars.  

[garageboy]

What does the headphone out section add in the circuit? 

 

[Jon L]

Headphone section is just adding resistors, the number of which is determined by Jumpers on top of the board (first photo is showing top of circuit board).  

The bottom of board shows Jupiter Copper Foil caps I rolled in place of (upgraded) Mundorf Silver/gold, and bottom right of photo shows resistor arrays for headphone output.

It's too bad the headphone jack cannot deliver enough power for my Abyss because it would have been so much more convenient to keep my speakers hooked up to speaker posts and Abyss to front headphone jack, which automatically cuts off speaker outputs  😞

 

Edited March 8, 2020 by Jon L

[spritzer]

I'd like to know what they were smoking when doing that input trace... clearly needs more vias... 

[garageboy]

I wonder if it's possible to jumper/bypass the resistors on the output - so you can use the headphone out direct from the transformers

[justin]

On 3/8/2020 at 4:43 AM, spritzer said:

I'd like to know what they were smoking when doing that input trace... clearly needs more vias... 

some sort of PCB twisted pair? or speed holes

[spritzer]

Speed holes...