Whest ps.30r

To Crystalref:

Could you provide some insights into how the operation of the PS.30RDT SE differs from that of the PS.30RDT? The statements on the Whest website don't really help me understand what is different about the operation of the PS.30rdt se that explains the 70% increase in audio reproduction relative to the ps.30rdt that is claimed on the Whest website (in fact, I really don't understand how that improvement figure was arrived at).

The photographs that you posted of the PS.30RDT SE circuit board were helpful. What was apparent is that the opamp circuits on the PS.30RDT board was replaced by these black boxes (which I presume are the discrete circuitry modules). I also appeared that the input capacitors in the PS.30RDT circuit board are replaced with large Clarity Cap capacitors.

Does the PS.30RDT SE provide more high end gain than does the PS.30RDT? In your case, 65 dB for a 0.3mv cartridge looks to me to be about right, but for a low output cartridge (for example 0.1mv), while 72 dB gain is adequate, I think that a gain level of more like 75 dB would be better.

Crystalref

With regard to my earlier question about the gain levels produced by the Whest PS.30RDT SE, I found the answer by looking at the photos that you posted on the Internet. In the PS.30RDT SE, the gain and resistance load levels are printed on the back panel. The high gain level remains at 72 dB but in the PS.30RDT SE, the low gain level is increased from 40 dB to 43 dB (which means that the Whest PS.30RDT SE will probably work a little better with lower output MM cartridges). It is also worth noting that the load resistance levels listed on the back panel of the PS.30RDT SE are correct, where the user manual has an error.

What do you think about having the access panel to the DIP switches on the underside of the case in the Whest PS.30RDT SE? I appreciate that Whest was responding to complaints about having to open the lid to set the switches, but what I don't like about the underside access scheme is that you have to turn the entire unit over to set the switches. I especially don't like having to handle the case because the casework is very prone to being smudged by fingerprints.

Paperw8

I can't really help you with the claims made by the manufacturer of a 70% improvement! This may be just marketing speak!. What I do know, having lived with the RDT and RDT 'SE' models is that the 'SE' is a substantial improvement sonically. The issue of acessing the DIP switches is only really pertinant if you swap cartridges alot. I don't. Apart from experimenting with load and gain for my Orpheus L when I first got the 'SE' home, I no longer have to access them. I have found that if you slide the phono stage forward from the rack and undo the two Allen bolts (way better than having to remove the unit entirely to undo NINE Allen bolts on the lid!!) to reveal the DIP switches, with the aide of a small mirror, you can make any adjustment you like easily without having to upend the unit. Whest advise and I can concur, that fingerprints/smudges can be easily removed by applying a small amount of WD40 to a clean lint-free cloth and running the cloth along the grain.

Steve

On the difference between the PS.30RDT and the PS.30RDT SE, my hypothesis is this (and it is just a guess): the PS.30RDT SE uses an opamp where the PS.30RDT SE uses a discrete bipolar module. So my guess is that the PS.30RDT uses negative feedback. Negative feedback designs are pretty controversial with some audiophiles; especially those who extoll the virtues of tube designs. I'm old enough to remember the transistion from tubes to transistors so in my mind I wonder: "why would anyone want to go back to that (tubes, that is)???"

My guess is that the discrete bipolar module is some kind of non-tube, non-negative feedback design.

As to the comment about preferring the access panel in the PS.30RDT SE, I see your point. I have my phono stage on the top shelf of a media cabinet so I can access the top lid of the phono stage without having to move it. I'm a bit of an inveterate tinker-er, so what I did was experiment with various gain and resistor combinations. I eventually closed the unit up, but eventually, I will reopen it and play around with additional resistor combinations just to see how they affect the sound. One thing that I like about the Whest phono stage is that the resistor values are moderately spaced so you can play with different combinations in parallel to "trim" the resistor value without having to go to the "user" resistor option. So, in my situation, top lid access works better because once I remove the lid, I can rifle through different combinations of switch settings.

I'm aware that you can use WD40 oil to clean the case but if you touch the case later, you'll get new smudges. I've taken to wearing latex gloves or using a towel to keep having oil from my fingers from staining the case.

Good theory and probably correct. James does state on his literature on the PS.30 RDT 'SE' that the sound is more 'valve-like'.

On the subject of doubling up resistor settigs to use in parallel. I recall reading this in The Stereo Times online review of the PS.30 RDT and discussed it with Whest. James thought it was a bad idea as he explained that it would simply add extra noise to the system. True or false, I don't know. I am not technically qualified to comment. In any event, I heeded James advice and only stick to the set resistor options.

I like your suggestion about using latex gloves!