Analog Squared Paper Discussion Thread.

[efftee]

I have been mulling over an A2P for a long time. Like the tube sound of the TUR-06, but hate the form factor. What does the TUR-07 sound like? Analog? Tube-like? Or just like other solid state amps?

 

[audionewbi]

He pays a lot of attention his amps and more importantly from what I have read they are best for low impedance gears.

Once I get the 07 I'll report back but the 07 uses Sit which is essentially a single chip which preforms like hybrid amp but lacks the need of tube. They are old and no longer made but those who can get ahold they swear by it.

 

[audionewbi]

More info on SIT
 

SITs look very much like solid state versions of Triodes, except that the voltage and current values are scaled differently. Tubes work at high voltages and low currents, and transistors are good at lower voltages and higher currents. The advantage for transistors is that these voltages and currents are convenient for driving loudspeakers directly and do not generally require an output transformer.

 source http://www.firstwatt.com/pdf/art_sit_nemesis.pdf
page 4

 

[efftee]

Thanks Audionewbi, I'd be keen to hear what you hear from the TUR-07. Though the thought of a 9V battery driving it for only 4 hours is a little off-putting. If only it supported USB charging and lasting at least 6-8 hours...

 

[audionewbi]

Usb charging is possible however charging and listening cannot be carried simultaneously.

 

[efftee]

Do you mean using an external charger on a rechargeable 9V battery or the unit has built in USB charging, just unusable during charging?

 

[audionewbi]

Yes, he is working on it.

 

[nevin]

OK. Finally have the courage to fix my mind on the TUR-06. Order placed with some weird requests to Shikada-san. Now waiting if he thinks they are do-able and invoices me.

 

[GermanGuy]

Great to see new participants and  life in this thread.
 
Greetings from Germany - GG

 

[woodcans]

I really want that mini SS amp. Looks super sexy!! Miss my TU-05 but don't have the time to sit down for extended periods these days. And yes, miss the good old days of this thread.

 

[nevin]

Great to see new participants and  life in this thread.

Greetings from Germany - GG

How's your amp going?

 

[GermanGuy]

One used TEN 3S4 available  in this set:
 
http://www.ebay.ca/itm/3S4-AUDIO-AMPLIFIER-RADIO-TUBE-4-piece-lot-/381212328873?pt=LH_DefaultDomain_0&hash=item58c20683a9
 
 
@nevin - slowly - really occupied by my job, but after having finished the general design of all components for my "highend" tu-05 mod some months ago i have started designing portable amps to  learn more about amp and  tube amp design and compact implementation.
 
by the way i had the idea  or maybe just wanted to build the (hopefully) worlds smallest tube amp , so here is my (really good sounding) candidate:
 
 

 

 
 
the size of the housing is 6 x 4 x 2 cm, it contains the amp shown above including 2 li-ion batteries, balancer-board, two submini tubes, two Double-Opamps, one on-off and two impedance switches, potentiometer, Input, Output and charger Input jack.
 
above the amp you can see the charger implemented as USB-Stick adjustable for 4.2 , 8,4 or 16.8 Volt 80 mA.
 
here is a better picture:
 

 
one tube per channel, the tubes are subminiature JAN 6418 tubes. the amp uses an dc/dc step down converter for the filament voltage with additional CRC filters per channel, the runtime is about 10 hours even with this very small 230mA li-ion batteries. to get a compact battery pack including the balancer /protection board i used two component epoxy resin to make one battery block. under the tubes are the opamp amplifier / buffer stages.

 

[nevin]

  @nevin - slowly - really occupied by my job, but after having finished the general design of all components for my "highend" tu-05 mod some months ago i have started designing portable amps to  learn more about amp and  tube amp design and compact implementation.

 
That look very awesome! What would be the output power? I'm signing up to buy one if you're going to produce it. :-D

 

[dj21]

I'm really IMPRESSED! Will very nice to have a micro tube amp to enjoy, hopefully one of these days... Thank you for your hard work GG, makes me dream..!!!

 

[nevin]

Now the waiting begins. I have received a confirmation email saying the production timeframe would be in July.