It is incredibly difficult to resolve issue such as this via verbal descriptions on an internet forum, but I do have a few thoughts. The D250 is a better amp, but I do not think the differences should be a stark as you are describing, so it does look like something is amiss. However, it could be many things.
1. The D200 is in some way faulty or substandard. - Unlikely perhaps, but it would explain everything.
2. The D250 works well with the OB1i's, but the D200 does not. Unfortunately I do not know enough about OB1i's to know how likely this is, but there is a possibility that there is some aspect of the OB1i's specification that does not agree with the D200, maybe a slight dip in the impedance curve somewhere that the D250 is happy with but the D200 is not. Although unlikely, this is a possibility because the key difference between the D200 and D250 is how the power supply is configured, hence making the D250 a little more speaker tolerant on the margins. One of the key things with hifi is getting an amplifier that works well with the speakers, and when this goes wrong things can sound bad.
3. Phycology! I need to be careful how I write this, because it could come across as a little insulting, but it is not intended to be. In fact, I am describing something that has happened to myself on a number of occasions. You get you lovely new hifi item, it has cost a lot of cash, you set everything up and start to listen. You maybe here some little thing that you don't like, and then thoughts start running through your head, have I bough the wrong thing, have I made a mistake? In this Physiological state you start trying different things whilst listening out very carefully to the aspect that has started to worry you in the first place. I know from my own experience that this kind of stuff can drive you crazy! Although I think that Devialet amps do improve very slightly with a few hours use, I do wonder how much of this is in the electronics or in the mind.
OK, these are just my initial thoughts and may be very wide of the mark. I have some questions. It looks like you have been trying different firmware versions and finding some differences. In order to judge your original post, you state a significant difference between the D200 and D250, how would you describe the order of magnitude of this difference in comparison to the differences between different firmware versions on the D200. I think most posters on this forum are familiar with how much difference the firmware makes, so this might help gauge the issue described in your original post.
As a final thought, as Damon correctly points out, there are number of people who much prefer firmware 7.1.3. However, this is not an absolute, myself I much preferred the 8.x.x and 9.x.x versions with my Expert. I guess a case of personal preference and system matching, but it would be incorrect to think that there is an absolute best firmware.
Anyway, good luck getting this sorted, I know how frustrating this kind of issue can be.
1. The D200 is in some way faulty or substandard. - Unlikely perhaps, but it would explain everything.
2. The D250 works well with the OB1i's, but the D200 does not. Unfortunately I do not know enough about OB1i's to know how likely this is, but there is a possibility that there is some aspect of the OB1i's specification that does not agree with the D200, maybe a slight dip in the impedance curve somewhere that the D250 is happy with but the D200 is not. Although unlikely, this is a possibility because the key difference between the D200 and D250 is how the power supply is configured, hence making the D250 a little more speaker tolerant on the margins. One of the key things with hifi is getting an amplifier that works well with the speakers, and when this goes wrong things can sound bad.
3. Phycology! I need to be careful how I write this, because it could come across as a little insulting, but it is not intended to be. In fact, I am describing something that has happened to myself on a number of occasions. You get you lovely new hifi item, it has cost a lot of cash, you set everything up and start to listen. You maybe here some little thing that you don't like, and then thoughts start running through your head, have I bough the wrong thing, have I made a mistake? In this Physiological state you start trying different things whilst listening out very carefully to the aspect that has started to worry you in the first place. I know from my own experience that this kind of stuff can drive you crazy! Although I think that Devialet amps do improve very slightly with a few hours use, I do wonder how much of this is in the electronics or in the mind.
OK, these are just my initial thoughts and may be very wide of the mark. I have some questions. It looks like you have been trying different firmware versions and finding some differences. In order to judge your original post, you state a significant difference between the D200 and D250, how would you describe the order of magnitude of this difference in comparison to the differences between different firmware versions on the D200. I think most posters on this forum are familiar with how much difference the firmware makes, so this might help gauge the issue described in your original post.
As a final thought, as Damon correctly points out, there are number of people who much prefer firmware 7.1.3. However, this is not an absolute, myself I much preferred the 8.x.x and 9.x.x versions with my Expert. I guess a case of personal preference and system matching, but it would be incorrect to think that there is an absolute best firmware.
Anyway, good luck getting this sorted, I know how frustrating this kind of issue can be.
1000 Pro - KEF Blade - iFi Zen Stream - Mutec REF10 - MC3+USB - Pro-Ject Signature 12
