Chameleon Labs 7602 and mkII, AC and DC power supply slightly different sounding?

[Audio Enginerd]

I have the original Chameleon Labs 7602 with the cps-1 DC power supply. I just got the 7602 mkII, and it comes with an AC power supply. I did a quick and not very scientific test of these two units side by side. The new unit was using the provided AC power supply while the original was using the DC cps-1. I found that the mkII sounds a little better than the original in this first test. It seems to have more focus, slightly larger bandwidth, maybe a little bigger low mid section and a shinier top. The top was a little more sibilant on my voice through a u87. However, these differences could be the slight changes in performance or mic distance from the sources. I tried to keep each take as close to the same position as I could. Then I changed out the power supplies and powered the mkII with the original cps-1 (DC). That time seemed a little closer to the sound of the 7602, but still slightly "better." Has anyone tested this themselves and had similar results, or do you think that it is more likely that the bigger contributing factors in the varying results were from the performance/source distance from the mic? DC vs AC? Also, has anyone noticed a sound difference between the original and the mkII in their default positions? I have the new units newly added ohm selector to 300. I would imagine that is what the original one is. I can't locate the manual for it at the moment. Oh, I was using the same cable and conversion channel in this test. These are the stock units without the mod upgrades. I was wanting to add this mkII so that I could have a matched pair of pre/eq, but I'm not frowning that the newer unit, at first glance, is sounding slightly better. Thoughts?

[buickwilson]

Do you notice a difference (the newer "lump" power supply in the cord vs the old "box" power supply) when using the EQ on the line input?

I tend not to use the 7602 mic pres, as I already have a rack of good pres (GML, API, Chandler) direct to PTHD, but I do use the 7602 for EQ's when mixing, and wondering if the power supply has much effect on the EQ and line level signals, and if there is much difference in sound between the old and new MKII when using just the EQ.

[warhead]

Cory, in my old rig Bob from SoundLab and I sat down with some new units running off the line lump transformer supply, vs my older units with the CPS-1. We both agreed that the new units with the line lump supply were a tad bit quieter vs the old using the CPS-1. Anyhow, that was that day in that room, but it was noticeable.

Both were modded units, but modded the same.

The mic input impedence is actually 1200ohm on the older units, the 300ohm option is added on the new units. Make sure you're listening to both with 1200ohm to compare.

War

[Audio Enginerd]

Haven't tried just the eq yet. Thanks War! Well, the ohm difference would make a difference then wouldn't it? I guess that explains the tonality difference. Would I be off base to assume that the higher ohm setting might be better for ribbon mics?