My original Spark from 12/2018 runs warm (they all do) and works as good today as when I first bought the amp. The heat from the Spark is not excessive and the amp is obviously very reliable. Just make sure you plug the power supply into the amp before you plug the power supply into the wall...

I bought two. I really like the Spark. I use the Spark as a headamp and as a preamp for my radio/tuner system. Absolutely a great product. The Spark has a lot of the LP sound quality for very little cost.

Numerous people in this thread have damaged their LP amps by connecting the power supply first and then connecting to the amp. You get an arc that kills the amp. I learned the hard way with a class D amp. Fortunately, that amp was very inexpensive.

I bought one when the amp first came out. Now years later I still think the Spark is the best entry level amp available. I like the Spark better than the Magni and the Piety, Asgard 3 etc... The Spark treble is so refined for an entry level amp and just does everything well. Best $100 bucks I...

Those adapters suck. I tried them and they did not even work. There is a head-fier here that makes great quality adapters .... Deyan. He posted back on the previous page. You pay a little more but the quality is top notch, he knows what he is doing and he ships very quickly. I have personally...

The gain is lower because the tube 12au7 tube inherently has lower gain than the 6922, Tubes have specifications and the mu/ gain of the 12au7 is around 19 and the gain of the 6922 is around 35. There is way more to a tube than the pinout. There is heater current draw, heater voltage, bias...

I do not have any issues with gain so the stock tubes gain is fine with me . I do have all the good USA 12AU7/5814's but my favorite tubes have been some 1971-1973 vintage Voskhod 6N23P. I read how good some of the Reflector 6N23P tubes were but I was not impressed with what I have. Several...

Adapting an external filament supply you built to the LP would be quite an undertaking even by someone with excellent DIY skills. The amp sounds great with the stock or NOS 6922 type tubes or the Russian 6N23P. Not bad with 12AU7 and an adapter but the gain is lower which can be good or bad...

If an amp has the ability to provide the additional heater current then this would work. I have bought 7N7 (6SN7) to 6922 adapters from you to use in the Garage 1217 amps. But those amps can provide up to 1.0 amp of heater current. The LP does not have that ability. You can only use tubes that...

This is wrong. You cannot use 6SN7's in the LP. 6SN7's require double the heater current vs the 6922 rubes .... 0.6 amp vs 0.3 amp. The LP transformer was not designed to provide that amount of heater current.

NO! Too much heater current required.

If you do not mind buying used the Monoprice Liquid Platinum is a great amp. Used LP amps are going for around $250 to $350 depending on what tubes are included. A unit with low hours and two sets of tubes just sold on ebay this last week for $244.50.

Reflector 6N23P/ Voskhod 6N23P/ Sylvania Jan 6922. I like the Voskhod the best with most of my headphones. But the absolute best sound was one particular combo with the Sylvania's.

Monoprice Liquid Platinum amp open box .... https://www.monoprice.com/product?p_id=36735

Monoprice Liquid Platinum amp open box .... https://www.monoprice.com/product?p_id=36735