I care about where things are made and try to buy U.S. made products when possible. In September 2001 the Chinese government treated our U.S. Navy EP-3 aircrew in a shameful manner. I try to avoid Chinese made products when ever possible.

It might depend on who built the O2. The JDS Labs built O2 amps are excellent. I also purchased an O2 amp from a different builder and it was bad, so bright I couldn't listen to it.

I can also recommend the JDS Labs OL DAC. It's a very smooth pleasant sounding DAC.

Yes, the other O2 was brighter than the Magni 3. I'm currently using the Denon AH-D600 headphones with the Magni 3 and I think it's a pretty good match.

I have two JDS Labs O2 amps as well and they are VERY good. I purchased an O2 amp from a different manufacturer which should have sounded the same as the JDS, but the sound was too bright. JDS Labs is a top notch company that produces excellent products. Their customer service is really outstanding.

I have a JDS Labs Element amp which I think is the same amp as the EL minus the DAC section. It is my favorite amp. There is a refinement to the JDS Labs amps that are a step above most other amps I have experience with. I also have the Schiit Magni 3 and the JDS is definitely the better amp IMO.

Yes, I've auditioned the HD598 as well and I like them, but still prefer the HD439 for its better bass performance.

The Focal Spirit Classic is one of my favorite headphones and they fit me quite well. These and my Beyerdynamic DT150s have the tightest sound I've ever heard in a headphone and no fatigue at all.

At a price well below your budget I would recommend the Sennheiser HD439. I auditioned the Sony 1A you are interested in and I prefer the HD439. I thought the bass on the HD439 was tighter and I think it is a more neutral headphone compared to the 1A.

I really like my Sennheiser HD439 headphones. Great sound for the price. Another high value headphone is the Sony MDR-ZX600.

Although I have not heard the Mad Dogs, I am very happy with my Focal Spirit Classic headphones. Very precise and as neutral a headphone as I have ever heard. I find the sound signature of the Focal to be similar to my modified Beyerdynamic DT 150.

I really like my Focal Spirit Classic and I think it may be a good alternative to the Shure 1540. I owned the Shure 840, but the Focal Spirit Classic is better in every way, especially the bass.

I would also recommend the Beyerdynamic T51p for your interests. It is the most comfortable headphone I have ever owned and it fulfills everything you're looking for. I really enjoy mine for all types of music. A couple of other headphones I have with really tight bass are the Focal Spirit...

I recommend Electric Avenues amps. I have two of them and consider them to be a great value. http://www.electric-avenues.com

I had the opportunity to audition the X1s at the local Hi-Fi store a couple of weeks ago. I found them to be very pleasant and I liked them better that the HD 600.

The Carver called "The Receiver" at 150 watts per channel is fantastic. Has the best tuner I have ever experienced. Sold it on eBay, but it is still one of the best pieces of Hi-Fi gear I have ever owned.

I attended the Rocky Mountain Audio Festival a couple of years ago and met some non-audiophiles that just happened to be visiting the hotel. They wondered in to some rooms and were shocked at how good the sound was. They told me they didn't know such good sound was possible.

I've always liked the M50, but I typically recommend the Sennheiser HD 439 for those looking for a high value headphone.

I hope to audition the Oppo headphones sometime. I've owned several of their DVD players and I trust they will provide a great product.

I had the opportunity to spend some time with the B&W P7 and it is very nice, although I do not consider it a good value at its price point.

I've been considering the iFi Micro iCan. Does anyone know if it ould have any advantages over the Nano?

The Audio Technica ATH-A900 is the most comfortable headphone I've ever experienced.

Why not stay with the ATH-M50 since you've been so satisfied with them? I use my ATH-M50 with a JDS Labs Objective 2 amplifier and I think they are a great combination. Or I can also recommend the Sennheiser HD439 or perhaps the Sennheiser HD25. Both have very nice impact.

True, not cheap. But the Sennheiser HD800 has authority below 20 Hertz that is incredible. Once you experience it it'll stay with you. I've never heard any other headphone that comes close to what the HD800 can do down low.

The most incredible bass I've ever experienced is with the Sennheiser HD800. Just amazing!! You will need a good amplifier though.