Phono stage revealing limitations of cartridge?


Hi,
I just purchased an Ear 834P for my system. This is my first experience with tubes. I hooked it up and I immediately noticed an improvement over the stock phono stage on my integrated. There was a much more three dimensional presentation. However, after listening for a few minutes, I realized the sound was very thin, light on bass, and the highs were bright and grating. Also, the output of the Ear is really high, so much so that the volume knob on my amp is almost all the way at the bottom and moving it very slightly results in a dramatic increase in volume. I'm wondering what is causing the bright sound. Here are the possibilities I've come up with:

1. The Ear 84P is just revealing the limitations of my cartridge which the stock phono stage had just smoothed over.

2. The stock tubes in it have gone bad. (I'm planning on trying out some Jan Philips 5751's on it to see if that lowers the gain a bit.)

3. The unit is defective/the person that modded it screwed something up.

4. I'm getting some very low level RF interference. You can't here it at all when music is playing, but if you turn it up all the way you can hear it. Perhaps this is causing the brightness.

5. The Ear and the Rotel integrated are a mismatch.

I've tried using a different cable from the phono to my integrated and that didn't change anything. I also tried using a different input on the amp. I tried both MM and MC to confirm that I am using MM.

Does anyone have any suggestions? I'd be really grateful if someone could help me get this sorted out. I know there's a lot of questions here, but I thought tubes would result in warmth, not brightness!!!

BTW, my system: VPI Scout/JMW-9, Sumiko Blue Point No. 2 (2.5 mV), Signal Cable Phono Cable, Ear 834P Deluxe Phono Stage (modded but w/ original tubes), Rotel 1062 Integrated Amp, Blue Jeans speaker cables, Infinity 3500 speakers (circa 1981)
sinisterporpoise68
The 834p has huge gain. Make a voltage divider with caddock metal film resitors and you will find things sound much better. The divider is very easy to make. Try 10k,5k,and 2k. The divider goes on the input of the line stage.

Tim
Hi all,
Got this figured out real quick when i opened the ear up to swap in new tubes: the tubes had been slightly dislodged during shipping. Either that or those stock tubes *really* sucked. I dropped in some Jan Phillips 5751's and this little box sings! I can't stop listening to records! Bass can be a little wooly at times but as the Ear warms up most of that gets corrected. This phono stage really sings and rocks. Music has never sounded so good in my house. Didn't even need to change the cartridge.

Thanks all for your generous help. Now to work on that RF...
This must be my lucky day. I just put in a VPI Phono Cable. RF interference gone. No more radio through the turntable. It really needs a good breaking in though.
Good to hear that you resolved your problems. My bet is that the tubes were going bad. But, it could also be the case that the 5751s are superior to the OEM tubes. Manufacturers must go with readily available tubes, in order to supply replacements to customers, even if there are superior alternatives. Readily available usually means in-production tubes.

With my Audionote amps, good vintage tubes were supplied by the manufacturer, but, these were somewhat common tubes (RCA 2a3s and RCA 5692s) and nowhere near the best possible tubes for these amps.

My phono stage uses 12AX7s too. I preferred the 5751s I tried with this phonostage over the manufacturer-supplied tubes, but I like Telefunken ECC83s and ECC803s even more. The ECC803 is, however, an extremely rare and expensive tube.