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Which attenuators do I want to use?

I was using a set of Rothwell RCA 10dB in line attenuators between my Jolida CDP and my Classe DR-5 preamp. One broke. My interconnects are Virtual Dynamics Davids which are a bit heavy. I'm now looking at other options. Thought about a set of Rothwell XLR 10dB attenuators to put between the preamp and amp for attenuation of all signals to the Pass Labs X-250 amplifier. Then there's another option I found poking around online, which is a set of 10dB XLR balanced line level fixed audio attenuators from Rackmount-Devices.com. These go for half the cost of the Rothwells, but I don't know what quality they are.
I found that when I was using the CDP with the Rothwells, I could only turn the volume up to about 8:30-9:00 position. Any more and it got a bit loud. Would a set of 20dB attenuators get my volume control up into the 10:00-12:00 position where I can get the best performance out of my preamp? A set of 20dBs from Rackmount costs the same as a set of 10dBs, I believe.
I don't want to spend hundreds. Just had my hearing tested, and, again, there is a small loss. I'm 52 years old. I figure I'll be able to remove the attenuators as my hearing gets worse. I think I'll have to get my wife some earplugs when this time rolls around.
Thanks in advance for any and all input.
128x128abucktwoeighty
abucktwoeighty's avatar
abucktwoeighty OP
1,079 posts
 
Bought the NHT PVC Pro, put it between the amp and preamp, and it attenuated the way it should, the way I want it to...but...now the music sounds compressed. The highs have faded, sound muffled, and the bottom end is now more pronounced.

Emailed NHT asking why. Their reply was to say that there may be an impedance problem, and possibly a gain mismatch because of where it is in the system. They also asked why it was placed between the amp and preamp. Said the PVC Pro uses very high quality Jensen transformers, and is passive, so zero ic's, etc. So any problem is a gain or potential impedance problem only.

Does this make sense? The unit is attenuating like it's supposed to. I know it's passive, but a gain or impedance problem should have no effect on the sound quality. The sound I'm hearing is like putting a new set of speaker wire into play. The last set of new cables I put in had the same effect, almost identical. Was wondering if it just needs time to work itself into the system like a new set of speaker wires.

What do you think?
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abucktwoeighty's avatar
abucktwoeighty OP
1,079 posts
 
My preamp is a Classe DR-5. The manual doesn't state the output impedance. As far as the return policy, I'm waiting for Monday to communicate back with them. As far as your offer to purchase it, I thank you for that, but don't feel you need to, or the responsibility for me making the purchase. It was my doing. There were other things I was looking at, but didn't fully investigate before I leaped. My bad.
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abucktwoeighty's avatar
abucktwoeighty OP
1,079 posts
 
The CD player has a 47K ohm output impedance. I thought about using it for the CD player, but as you stated, there will be a mis-match, plus, it has XLR jacks, which will not work. RCA's there.

I'm still waiting for a reply from NHT.

In the meantime, I'm still searching for something work with the CD player that will attenuate around 20dB. I've given up on finding something that will work between the amp/pre. Like you said, my best bet there would be to get a different pre with less gain. That is not an option at this point in time, so I'll look for something like I was using earlier, like the Rothwells. If I can attenuate the CD player, I'll be happy.
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