Timb5881

Don’t forget the early Koss estats! The ESP 6, 7, 8, 9, and the 10. I have the ESP 6, ESP 9b, and the ESP 10, all sealed. I am sure this new one will seriously out perform all my Koss headphones.

Or it could be that they are using sources such as DAPs or USB stick amp/ DACs, they can use a bit of a boost.

I would love for you to do a write up the D amps. I use one of 3 amps with mine. The Golden Tube SE40, the Aragon 8008, and a Carry Rocket 88 are my usual suspects for amplifying headphones. I do have a few other amps that I could use but they need repair.

I am glad you told me that, I would not want to buy bogus transistors. So with that in n mind, I will continue to use my SRD-7 Pro and my SRM 212, and save up for a better amp.

So if I use them as. A sub. Is this a plug and play transistor or do I need to mod something.

Thanks Spritzer. I know I asked you if there were subs for those transistors.

I was looking for 2SB832 four of them

Yes the older Stax amps do offer a way into the Stax world. But be weary that many have parts that are no longer available. I have a Buyer beware on older Stax amps. Many have parts that are no longer available. I have a SRM 1/ MK2 that I tried to refurbish but some of the transistors are not to be found at any price. I know the Stax SRM1 is loaded with obsolete discontinued parts. If you were to look at this point of view, Topping at least has modern and available parts. Design wise the topping is iffy at best. Maybe Birger and Mr Gilmore can give us a list of Stax amps that have replacement parts issues so others can make better informed decisions.

Look up online the owners manuals of Koss ESP7,8,9 and they have a oscope printout of a 400 hz square wave. It looks as bad as the Topping. These models of the ESP all use an external transformer box (the ESP6 had its transformers in headset, heavy and uncomfortable) hfe_koss_esp-7_en 2.pdf

Based on measurements only, and Topping products usually measure very well.

Interesting write up Spritzer. When you have time, tell us what changes Topping should make.

The old SRD-x Pro was a transformer driven by an amp. That may be a he best comparison for this amp.

Get a Stax SR003 and the cs1 kit. Isolates very well If you are taking it somewhere there is the SR002 iem portable. I have the SR002 and an adapter so I can use it with a SRM 212. The little battery operated amp is actually pretty good.

Has any one seen a Stax SRM-1/MK2 like this before?

Hi Our Man in Paris Thanks for that info, and that is a very good analogy of cameras.

Just dropped to best price yet, $249.99. Well worth that price

Has anyone used the Sigma headphones for listening to pop/rock or blues? If so how do they handle that type of music?

Any one have any experience with ES Labs Sigma headphones?

Has any one purchased one of these? If so what are your impressions?

Bad news, Monoprice raised the price back up to $629. To much in my mind.

Well it arrived yesterday. I have a ground hum issue, my house unfortunately only has 2 prong no ground. I am going to run a ground cable out the window and try and see if that works. Low bias works ok, as does the pro.

Yes, I was the only bidder.

Just purchased a Stax SRM-1/MK-2 amp, with one side converted to a pro bias out put. Seller say's everything is working ok, just a worn looking case. I hope I like it with my SRX-3 MK III normal bias headphones.

Sop Spritzer, that divider could take it down to 300 V?

Has anyone actually verified the Bias out of the E90? Some say it is only 300 V versus some saying 600 V (which is what is stated by Koss).