When you consider the cost of your fine system, why quibble over the $30 difference between Harrison & Rothwell Attenuators? Your speculation about use of attenuators and future hearing loss is off base in my opinion. First of all, most of us have age related hearing loss that's in the upper octave of musical frequencies. The rest of the frequency spectrum remains fairly equivalent to our younger years. A little loss across the board isn't go to result in a situation that will warrant removal of attenuators. Besides, if we have the financial resources, there's no reason not to get hearing aids to augment our hearing. My wife has some of the newest technology digital aids and is thrilled at how well they work for music.
Rather than guess at how much attenuation you might need, you might consider (if you can still find one) an NHT PVC Pro
. It's balanced (Jensen transformers) so place it between your pre and amp.
Photon46, I understand where you're coming from. I've been debating on whether keeping the whole system or just getting rid of it. I love it, but I find myself falling asleep often during listening sessions, or just thinking about alot of other things I could (should) be doing instead. I fall asleep because I work long hours. The cost really makes little difference in my decision, since the option Bob Reynolds posted looks to be the route I'll go. Just trying to save a few bucks. Thanks to you both.
Was able to order a NHT PVC Pro online fron their website, so they must still be selling the inventory.
Yep, it turns out that NHT is back... as an online company. I hope they continue to provide the PVC and X2 products and, of course, their classic speakers.
I HAD THE SAME PROBLEM,INSTEAD OF TRYING DIFFERENT ATTENUATORS I BOUGHT A RICHARD LEE PASSIVE PREAMP AND I PUT IT BETWEEN MY TUNER AND PREAMP,IT HAS A VOLUME CONTROL SO YOU CAN AJUST IT TO WHAT VOLUME YOU LIKE.NO MORE GUESSING ON WHAT TYPE OF ATTENUATORS ANYMORE.GOOD LUCK.
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?
Yes, that makes sense. From the Pass web site, I think your amp has a 20 kohm input impedance on its balanced inputs. So using the general 10X rule of thumb, you should use the passive where its output impedance is less than 2 kohm. You can use an ohmmeter to detemine this point. There will also be an impedance matching issue between your preamp and the PVC. What preamp are you using? And what is its worst case output impedance?
I apologize for not bringing up the potential impedance matching issue in my original post. Since you made this purchase on my suggestion, I feel responsible. I don't know what NHT's return policy is, but if they won't take it back I'll give you $120 for it.
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.
Assuming your preamp is solid state, its output impedance is probably low enough to be fine with the PVC Pro. The PVC is listed as having a 4.7 Kohms input impedance (this will also be its highest output impedance), so as long as the output impedance of your preamp is below 470 ohms across the audio band things should be OK. The amp side will be an issue unless you turn the PVC's volume up enough so that its output impedance is less than 2 Kohms.
A couple of years ago I measured the original PVC that I own (5 Kohm pot) to check its channel tracking and the output impedance was 1700 ohms at 75% of max volume. However, doing this will not attenuate the signal enough for you to get the volume control in your preamp you desire.
You'll likely have the same problem with the CD to preamp interface. The Jolida CD, being tubed, will likely have a high output impedance and this will be a problem for any passive attenuator. Unless your preamp has a much higher input impedance (say 50 Kohms) than your amp, you'll have an issue between the attenuator and the preamp.
The problem you face is a gain mismatch between your preamp and amp. Any passive device, no matter the manufacturer, will have the same limitations. The only way to drop the voltage enough (to get the attenuation you desire) will be to insert a resistance that could be too large for either the source or load.
I believe that ultimately you'll need a different preamp with less gain. I stand by my offer, I should have made the impedance issues clear.
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.
After talking with John at NHT, they sent a return authorization number for a refund. Nice folks to deal with.
Will be trying something else in the near future.
Since I found it hard to believe that a CD player (or any device) would have an output impedance of 47 Kohms, I contacted Jolida and discovered that their web site is in error.
The actual (Michael Allen didn't specify a frequency) output impedance is 47 ohms -- 1000 times less.
Their manual is in error as well.
I'm waiting for delivery of the CI passive controller which should work nicely between the CDP and preamp. It's been rough listening without attenuation. Three steps on the volume control is too loud for my wife, two steps is too low for me.
Received the Channel Islands VPC 3 passive controller today. Put it between the CDP and preamp with excellent results. Attenuates the signal so I can use my preamp volume control with better precision. The unit disappears. I don't even know it's there.
Glad to hear it finally worked out. I had contacted CI about the impedance of their passive, but never received a reply.
I own a Classe DR-6R and I put a voltage divider in mine with a new Gold Point Attenuator and I love it. If you can solder I will send you some information on putting in a voltage divider or you can look it up online. It is just 2 top resistors of a certain value to get the dB change you want. I wanted a little more control over the volume. I am not a fan of outside attenuation but that might be the easiest, but they can change the sound in a big way.