[Dillan]

Thought it was worth starting a thread for a very unique amplifier from the company ampsandsound.
 
Here is my review: http://www.head-fi.org/products/ampsandsound-agartha-single-ended-amplifier/reviews/16965
 
 

 
Here is the description from the site:

Agartha

The name Agartha used to describe a city in the center of the world. The ampsandsound Agartha brings the legendary 300b to personal audio. We chose the 300b for its long history as the king of triodes. Combining a single gain stage, zero feedback and careful attention to grounding techniques we are able to use a 300b with headphones without hum or noise. For those with headphone, horns or single driver speakers who are seeking audio nirvana, the Agartha is built with exacting attention to parts selection and implementation.
The Agartha tube amp pairs a 6SL7 tube for front end with SS rectification enabling great transient peeks, faster/livelier presentation and ultra-quite operation. The Agartha uses direct-heated triodes with zero feedback providing the classic single-ended sound so widely loved.
Typical of all ampsandsound amplifiers, the power supply is massive. This combined with a generous choke yields our trademark low noise; less than 3mv at idle, and stable output of 5 watts RMS into an 8ohm load and 1watt into a 32ohm headphone. Frequency response is 12hz to 30hz at 1 watts, 1-db. Output iron has been carefully selected to reduce distortion and increase frequency response. And of course we also use our 5% capacitors and 2% resistors.
The motivation of the Agartha is to provide access to the wide availability of NOS tubes and give the warm mid-range bloom that is at the heart of single-ended direct-heated triode designs. Tube set included.
Input Sensitivity: 840mV RMS for full power
Max Power: 5watts RMS into 8ohms
Max Power: 1.5watts RMS into 32ohms
Noise: 760 uV as measured from 8ohm Tapp
Noise: 660 uV as measured from 32ohm Tapp
Power Bandwidth 20hz @ -.5db down to 20Khz @ -2db down as measured from 8ohm Speaker Tapp measured at 1 Watt RMS
Power Bandwidth 20hz @ -.5db down to 20Khz @ -4db down as measured from 32ohm Headphone Tapp measured at 200mWat RMS
Agartha $3,600 with tube set.

 

[MLGrado]

Nice review.  
 
I will be in the market for a new tube amp in the next few months.  
 
 
My issue is I have several hundred NOS 12AX7, 5751, 7025 etc, and several hundred NOS 12AU7, 5814, 7189, E82CC, 12BH7A etc.  
 
Not a bad problem to have , but it limits my choices lest I want to start a whole new collection of NOS tubes, and considering how much $$$ I have dumped into what I already have, that isn't really an attractive choice.  
 
 
For the right amp, though, I would do it.  A sell off of a hundred or so tubes would fund the amp purchase itself.  And even a few NOS 6SL7.  
 
(I actually have a few 6SL7, and an adapter that lets me use them in place of 12AX7.  Bigger soundstage with the 6SL7)

 

[Dillan]

  Nice review.  
 
I will be in the market for a new tube amp in the next few months.  
 
 
My issue is I have several hundred NOS 12AX7, 5751, 7025 etc, and several hundred NOS 12AU7, 5814, 7189, E82CC, 12BH7A etc.  
 
Not a bad problem to have , but it limits my choices lest I want to start a whole new collection of NOS tubes, and considering how much $$$ I have dumped into what I already have, that isn't really an attractive choice.  
 
 
For the right amp, though, I would do it.  A sell off of a hundred or so tubes would fund the amp purchase itself.  And even a few NOS 6SL7.  
 
(I actually have a few 6SL7, and an adapter that lets me use them in place of 12AX7.  Bigger soundstage with the 6SL7)

 
That's quite a collection of tubes!

 
My advice would be to choose the best sounding amp regardless of your current inventory of tubes. A nice hint though - ampsandsound is coming out with a new amp (at a lower price than the Agartha) at RMAF next week. I was lucky enough to get a pre-release unit and ended up buying it! Both amps are amazing, just depends on tubes and which headphone/speaker you are using.

 

[Pawn]

Thanks