Volleyguy,
Stereophile tends to like items that you can buy new in a salon. They are not going to recommend a harder to find, vintage production tube that is generally only available used. The EH 7591A is a "nice" output, better than the JJ in my opinion, the latter being a little tizzy on top at times. But its fat size aside, the EH simply does not present the midrange presence of a Westinghouse, or a coin base Sylvania for that matter. Also, none of the current production 7591As have the grid leakage tolerance of the older production. While potentially pricey, I would try to hunt down a good quad of old Westinghouses (old as in used/test strong, as brand new quads are quite rare). They will be a significant step up from an EH. They are also less likely to break down than an EH can in the wrong circuit.
The 7591A is an interesting tube. Some would say it is the least tube-like sounding output tube, and it was quite a marvel of engineering at the time, being one of the last major output designs. It will be punchier and go deeper than a 6BQ5, especially in a SS rectified Fisher. Because only two manufacturers produced it during the vintage era, whatever brand you locate will be a Sylvania if a coin-base, or a Westinghouse if not.
The beauty of a good 6BQ5 is its middle, which is unmatched in my opinion. It is not powerful, but you don't need great power with horns.
Just as with passives, it is sometimes good to mix small signal tubing across stages to a desired result. Using all of one manufacture can sometimes be counterproductive. One sage piece of advise if you intend to start rolling: buy used/test strong stock. It is MUCH cheaper and you will have much more variety to choose from than with NOS. And most used/strong tubes will last just as long as an NOS. It is also a lot more fun.
At this point, I do NOT recommend running any Fisher tube instrument bone stock. Repairing individual items as they fail is not a good course at this point. Again, go check the vintage forum archives at AA for particulars on what should be done. I know I've written a lot there over the years. In particular, once the bias supply is updated, any 7591A will lead a longer and much cooler life.
It really is not fair to compare the original X-101 with the later X-101-D until both have been properly reconditioned. The former is now 50 years old, and is in dire need of reconditioning. It is no wonder it may not sound competitive. But of that family, I prefer the X-101-B the best.
If you really want to enjoy the Fisher tube sound, the pinnacle is the 400CX2 preamp. In my main system, a fully restored example feeds a larger Classe/Thiel pairing to delightful effect.
Stereophile tends to like items that you can buy new in a salon. They are not going to recommend a harder to find, vintage production tube that is generally only available used. The EH 7591A is a "nice" output, better than the JJ in my opinion, the latter being a little tizzy on top at times. But its fat size aside, the EH simply does not present the midrange presence of a Westinghouse, or a coin base Sylvania for that matter. Also, none of the current production 7591As have the grid leakage tolerance of the older production. While potentially pricey, I would try to hunt down a good quad of old Westinghouses (old as in used/test strong, as brand new quads are quite rare). They will be a significant step up from an EH. They are also less likely to break down than an EH can in the wrong circuit.
The 7591A is an interesting tube. Some would say it is the least tube-like sounding output tube, and it was quite a marvel of engineering at the time, being one of the last major output designs. It will be punchier and go deeper than a 6BQ5, especially in a SS rectified Fisher. Because only two manufacturers produced it during the vintage era, whatever brand you locate will be a Sylvania if a coin-base, or a Westinghouse if not.
The beauty of a good 6BQ5 is its middle, which is unmatched in my opinion. It is not powerful, but you don't need great power with horns.
Just as with passives, it is sometimes good to mix small signal tubing across stages to a desired result. Using all of one manufacture can sometimes be counterproductive. One sage piece of advise if you intend to start rolling: buy used/test strong stock. It is MUCH cheaper and you will have much more variety to choose from than with NOS. And most used/strong tubes will last just as long as an NOS. It is also a lot more fun.
At this point, I do NOT recommend running any Fisher tube instrument bone stock. Repairing individual items as they fail is not a good course at this point. Again, go check the vintage forum archives at AA for particulars on what should be done. I know I've written a lot there over the years. In particular, once the bias supply is updated, any 7591A will lead a longer and much cooler life.
It really is not fair to compare the original X-101 with the later X-101-D until both have been properly reconditioned. The former is now 50 years old, and is in dire need of reconditioning. It is no wonder it may not sound competitive. But of that family, I prefer the X-101-B the best.
If you really want to enjoy the Fisher tube sound, the pinnacle is the 400CX2 preamp. In my main system, a fully restored example feeds a larger Classe/Thiel pairing to delightful effect.