Tube Depot Tubecube | 7

RDavidson · « **on:** 29 Sep 2015, 04:05 pm »

Looks like we have a US direct source for the well regarded MiniWatt / APPJ tube amp. Also, doing a quick search, Tube Depot's price is better than I've seen elsewhere, typically $200 + shipping from China.

$179.95 from a reputable US source makes it VERY tempting.

https://www.tubedepot.com/products/tubecube-7-stereo-vacuum-tube-amplifier

FullRangeMan · « **Reply #1 on:** 29 Sep 2015, 04:17 pm »

Do you will order one?

RDavidson · « **Reply #2 on:** 29 Sep 2015, 04:36 pm »

Getting one of these is not a priority for me right now, but I likely will at some point.....perhaps by next summer when it gets too warm in my listening area to run my Pass amp comfortably.

FullRangeMan · « **Reply #3 on:** 29 Sep 2015, 04:45 pm »

Too bad it dont double as preamp or headphones amp.
It would add more value to the product.

RDavidson · « **Reply #4 on:** 29 Sep 2015, 06:32 pm »

Here's some useful info on the Tubecube 7, including measurements.

http://www.kenrockwell.com/audio/tubedepot/tubecube-7.htm

FullRangeMan · « **Reply #5 on:** 29 Sep 2015, 06:48 pm »

6 ohms are a rare feature on tube amps.
It more suited to 8 ohms speakers than 8 ohms taps.

1BionicEar · « **Reply #6 on:** 30 Sep 2015, 01:31 am »

I have the MiniWatt version. It won't make your eardrums bleed, but it is excellent for a nearfield setup. Good upgraded tubes are pretty cheap. Hard to beat at that price. No experience with the speakers they are bundling. I used ERA Design 5s.

RDavidson · « **Reply #7 on:** 30 Sep 2015, 02:27 am »

Yeah. The MiniWatt / APPJ is purportedly quite nice for desktop use and/or for speakers of highish sensitivity, despite its bargain price. I'm surprised more people haven't taken the little amp and tweaked it. Hopefully Tube Depot offering it will tempt more folks to get one. I mean, a lot of us spend much more on cables. Certainly this little amp is a much more entertaining purchase dollar for dollar.

Poultrygeist · « **Reply #8 on:** 30 Sep 2015, 10:44 am »

There were a couple of common mods on the original S1 MW. As I recall they were discussed on the old Hornshoppe Horn forum. Ed Schilling did the 5 minute diode mod on mine and the improvement was noticeable.

Poultrygeist · « **Reply #9 on:** 30 Sep 2015, 11:04 am »

This 4 tube APPJ has the same tube compliment as the original MW S1 and is billed as such.

http://www.amazon.com/APPJ-mini2013-Original-miniwatt-Amplifier/dp/B00JSNLU36/ref=sr_1_7?ie=UTF8&qid=1443610188&sr=8-7&keywords=appj

I've spent time with the APPJ N3 ( aka tubecube ) which is very good but I liked the original S1 a little better.

Could be my diode mod or the better sounding Western Electric 403B's substituted for the 6J1's or the Russian 6P1P-EV substituted for the 6P1's.

RDavidson · « **Reply #10 on:** 30 Sep 2015, 03:09 pm »

As they changed the design to have a single driver tube, it makes me think that the output tubes must have a larger influence on the sound than the input tube(s). So the simplification of the circuitry, even if it doesn't make a big difference in performance, makes tube rolling easier and less expensive. One would just need to be sure to buy a driver tube with matched sections, which isn't a big deal at all.

This generally bodes with my experience with tube amps (output tubes being the primary influencer on the resulting sound), not that the input tubes don't make a difference. They certainly do.

I would imagine that most tweaks done on the original are applicable to the newer version. I'd like to see people pick these little amps up and tinker with them, much like back when the little plastic T-amp was all the rage : better power supply, better volume pot (or bypass it), chassis damping, better connectors, etc. That sure was a fun time back when the original T-amp (and its successors) were all over the audio headlines and people everywhere were enjoying them and tweaking them. I think this little tube amp has untapped potential.

Mr. Oczka · « **Reply #11 on:** 30 Sep 2015, 03:25 pm »

Do u guys have any recommendations for diy speakers to run with these, probably used as desktop speakers?

RDavidson · « **Reply #12 on:** 30 Sep 2015, 03:57 pm »

I'd go with the Super 3 Desktop or 3i Omegas. But as you asked for DIY I'd certainly side with high sensitivity / high efficiency single driver kits, like this:
https://www.madisoundspeakerstore.com/2-way-speaker-kits/fostex-p1000e-diy-kanspea-4-full-range-speaker-kit-pair/

FullRangeMan · « **Reply #13 on:** 30 Sep 2015, 06:19 pm »

Quote from: Mr. Oczka on 30 Sep 2015, 03:25 pm

Do u guys have any recommendations for diy speakers to run with these, probably used as desktop speakers?

Surely a full range driver:
http://brinesacoustics.com/Pages/M12-A12/Main.html
Or some more sensitivity:
http://www.commonsenseaudio.com/an10classicspecs.jpg
But a 99/100dB sensitivity driver will be more dynamic.

randytsuch · « **Reply #14 on:** 30 Sep 2015, 10:27 pm »

The LGK's from GR Research (have a circle here) are nice single driver desktop diy speaker. There are flatpacks available, makes it an easy diy build.

Poultrygeist · « **Reply #15 on:** 30 Sep 2015, 10:42 pm »

If you want to go DIY cheap these would work. 91 dbs would be fine with a 3 watt amp in near field. The Pioneer Bofu would be a better choice but they aren't made anymore. I've seen a few on the bay. The GRS is supposed to be a clone of the Pioneer.

http://localhifishop.com/blog/2014/06/19/tweek-geeks-summer-speaker-project/

RDavidson · « **Reply #16 on:** 1 Oct 2015, 12:44 am »

Quote from: randytsuch on 30 Sep 2015, 10:27 pm

The LGK's from GR Research (have a circle here) are nice single driver desktop diy speaker. There are flatpacks available, makes it an easy diy build.

Those LGK's are pretty cool. As they're somewhat tall, one probably wouldn't need desktop stands ; Maybe just some little footers or something so they tilt back slightly, depending on how tall you are or how you prefer to sit at your desk.

cody69 · « **Reply #17 on:** 1 Oct 2015, 01:33 am »

Quote

Quote from: randytsuch on Yesterday at 10:27 pm
The LGK's from GR Research (have a circle here) are nice single driver desktop diy speaker. There are flatpacks available, makes it an easy diy build.

Those LGK's are pretty cool. As they're somewhat tall, one probably wouldn't need desktop stands ; Maybe just some little footers or something so they tilt back slightly, depending on how tall you are or how you prefer to sit at your desk.

I like these little guys. The cabinet design has the center of the driver about 10" above the surface the speaker is sitting on. Mine sit on raised platforms on both sides of my monitor, which places the driver about ear level. Driven from a little TPA3110 amp, these sound great.

Danny commented on this amp/speaker pair yesterday in a thread over in his GR Research circle --

Quote

I've just moved offices and I'm thinking of getting a better office system. Would these work with a flea powered amp, like one of these or even a headphone amp?

https://tubedepot.com/products/tubecube-7-stereo-vacuum-tube-amplifier

That would be just enough power to drive them as desk top speakers if you are sitting right in front of them.

That little amp is certainly cheap enough. The power cable I'd plug into it cost twice that much.

RDavidson · « **Reply #18 on:** 1 Oct 2015, 01:42 am »

Oh cool! Thanks for closing the loop regarding pairing the LGK's and the Tubecube 7, Cody. Very helpful. Good to see others are looking into this exact combo too.

JLM · « **Reply #19 on:** 1 Oct 2015, 02:13 am »

Laws of physics say it's hard to combine efficiency, small size, and bass response. The above speaker suggestions have issues:

The Brines M12-A12 are floor-standers and cost 10 times what the amp does.
The Common Sense speakers are even bigger (Vas = 180 liter - 6.6 cubic feet).

The LGK's are 87 dB/w/m (should be OK for desktop use - only reaches down to 70 Hz and with the Tubecube would only reach 91 dB).

The DIY option hadn't been built, tested, or listened to.

The Brines Acoustics T7-A7 (about $370 for flats kit and drivers) would make more sense price/size than the Brines/Common Sense above suggestions, are a proven design versus the DIY option, and provides better sound/more flexible (possible in-room use with a sub) than the tiny LGK for roughly the same price when cabinets are accounted for.

Also check out Planet10 hifi.com for his proven smaller speaker complete kit designs. (Dave is a member here at AC.)