PV-14L: Tubes and Tweaks

[Wildcat]

With the PV-14L settled into its new home, I'm thinking of doing a few minor tweaks.

This is the "S2" version of the preamp (factory upgraded, $600-ish), but it was shipped to me with a set of JAN Philips ECG 6C4WA tubes that were getting a little long in the tooth. This upgrade was done a few years back, so the Mullards that C-J put in it after the upgrade are long gone. The previous owner figured these 6C4s were used around half of their lifespan. I ordered in a pair of Tung-Sols and after about 15 minutes or so, I do hear a slight difference. Slightly less bright on top (not so "etched", if you will), but the bass remained full. Once these get a few hours on them, I'll have some impressions on them.

Once the next payday rolls around, I'm going to ordering a pair or two of the Mullard M8080s (which CJ recommends), along with a couple of other 6C4 pairs just for kicks.

One thing I noticed is how microphonic these tubes are. I have a couple of other tube pieces in other systems, and it seems that the 6C4 seems to rattle a bit if the C-J's case is tapped. Even pushing the volume buttons, I can hear them. The tubes did come with dampening rings, so that's a plus. I am considering using some isolation feet under the preamp, and possibly even dampening the lid with some sound deadener.

Just nitpicky little things, but nothing serious. This is a definitive step up from my previous preamp! Plenty of good listening ahead.

[jeffreybehr]

My MET1 uses a half-dozen M8080s. After I bought it many years ago, I tried MANY brands of 6C4s, but I tossed almost all because they were very microfonic. The Mullard M8080/CV4058 is a MUCH-better-sounding tube--typical-Mullard slightly warmish MR and excellent bass and treble. I didn't find many 'plain' M8080s, but the CV4058--the military-spec equivalent to the M8080--is findable on eBay. Buy 'em--they're worth it. Toss the 6C4s.

I use Herbie's Audio Lab Tenderfoots* under all my electronic equipment, and I use SoundCoat the Thicker** on all the ringing panels.


* 'Tenderfoot' is Steve Herbelin's trade name for these quishy feet, and I've never seen Steve use the plural form 'Tenderfeet', so I guess the plural is 'Tenderfoots'.
http://herbiesaudiolab.net/compfeet.htm

** http://www.soniccraft.com/product_info. ... -gp-p-4620 You might think it's expensive, but it REALLY works.

[Wildcat]

Good evening, time for an update! I finally received my CV4058s and indeed, not microphonic so far that I can tell. What I noticed about the tubes that came with the preamp was that when you tapped on the tube, you could hear the grids rattling inside. Not so with the CV4058s. I did like the sound of the Tung-Sols, but found them perhaps a bit more "dry" than these Mullards, which are still breaking in. I agree they have a "richer" presentation, sounding quite good with just about anything I threw at them today (from classical to Bill Evans to Stevie Ray Vaughan).

The SoundCoat does not seem that expensive for what it does--I might order some in soon, both for the preamp and the digital player. The Tenderfoots/feet/whatever are interesting! Still weighing my options there.

[engie3245]

I just picked up a PV14, but it is basically unusable due to a microphonic tube in one channel. I've ordered a matched set of Mullards and I'm looking forward to listening to them.

Does anyone know what the differences are between the original PV14L and S2? I've seen the cost ($600) listed but no description of what is actually changed during the upgrade.

I've seen a PV14L with the output caps changed to Dynamicaps, but not much beyond that.

Thanks!
Jeff

[Big Dog RJ]

G'day mate, nice find on the PV14L.

I wasn't aware that there was a PV14L series 2... didn't reach our markets here, so maybe a US or European version, don't know.

However, if you're saying that one has been modded with Dynami-caps, then that's great! I've heard other gear with Dynami-caps, they sound more transparent and higher definition, and do cost more than the polystyrene or polypropylene caps that CJ sticks with in the non-Premier range. So changing to Dynami-caps is more of an upgrade if anything.

Can't really comment on the Series 2, other than the standard version of the 14L, which is still a darn good preamp. I think it uses the same tubes found in the PV15, which were the M8080 Mullards (CV4058) miniature Triodes. Very musical indeed, and the same ones used in one of CJ's newer preamps, the Classic SE preamp. I really enjoyed my time with the Classic Pre, which had musicality to the core! Although, unlike the PV14L & PV15, the Classic Pre didn't have remote nor any digital interface, it was completely analog. It's a shame it was succeeded by the Classic 2/se that didn't use the Mullard M8080's any longer, rather CJ changed over to the 6922 variant. Using just one tube in the Classic 2/se and now it's been discontinued. Even with the series 2 on the Classic pre, I simply preferred the earlier version using the M8080's, a marvelous preamp!

Sorry mate, not much help there. In any case, since you've ordered the Mullards (M8080's) and requested for matched pairs, once installed, they'll work fine!
Cheers, and do enjoy those fine tunes.
RJ

*Btw* I order my Mullards (M8080's) from a UK supplier, Watford Valves (Derrek) great chap to deal with. If Derrek doesn't have stock, then I get them directly from JF at CJ HQ. They're bit more pricey but worth every penny.

[Wildcat]

I ordered my M8080/CV4058s from Colomor (via eBay). But that was several years ago, when I stocked up. They don't have as many available now as they used to. When I came across a bad tube early on, they shipped me a replacement pair of tubes, no charge. That is when I ordered another couple of pairs for the future, so they could ship together. I'll bookmark Watford Valves as another supplier, as I may order one last pair before I move on to something else.

[engie3245]

Thanks for the responses!

I ordered from Watford as well, so I’m happy to hear they took good care of you! I got an email today saying the package is with the Royal Mail.

I looked inside my PV14 today and it has Philip’s 6C4s, so I’m not surprised by the microphonics.

I took a picture and compared my board to an S2 version on the web and only noticed a couple of changes. I have blue resistors just to the outside of each tube and the S2 has much larger black resistors. Also, there is an additional 20uf cap near the front of the main board that is empty on my preamp. That’s all I could see.

I don’t know if anything else was changed to different values but identical looking parts. I can easily get a tech to add another 20uf cap, but I’m not sure if the resistors have different values or are just different parts with the same value.

As I mentioned, I found a pic of a PV14L where someone had swapped out the CJ output caps with Dynamicaps. They went with 5.1uf caps instead of the 4.0uf caps CJ installed. I would bet the bypass caps are slightly different values from the 0.15uf ones CJ used.

Of course there are a ton of options for changing those caps out. But I’d just like to get good tubes in it first and go from there.

Jeff

[admin]

I agree with you. I think going with new tubes is the best option here.

I am not sure what the difference between the original and s2 version is either. Interesting that CJ's website doesn't even mention the two flavors.

[Joe Appierto]

Interesting that at one point The Music Room offered the Series 2 for sale: https://tmraudio.com/components/preampl ... qXKiTa11kq

And here's something from NBC News regarding the Series 2. You'll note they list the price as $2,395. I believe the original model listed for $1.995.

Conrad Johnson PV14L Series 2: Wow! This is a beautiful device. Seven inputs, improved components in the circuits and this preamplifier sounds like it costs a lot more than you actually have to pay for it.


Give this baby some time to break-in and you’re rewarded with the smoothest and crispest sound I’ve ever heard from a tube unit. The PV-14L Series 2 ($2,395) always sounds musical and it reproduces a pretty credible soundstage with the DeVores. Highly recommended — and a good match with the HCA-2 above and also Conrad Johnson’s MV-60 amps. Plus, and this is a big plus, there’s a remote control for both the volume and to select what input you’re listening to. That’s worth the price of admission all by itself."

[Wildcat]

I took a picture and compared my board to an S2 version on the web and only noticed a couple of changes. I have blue resistors just to the outside of each tube and the S2 has much larger black resistors. Also, there is an additional 20uf cap near the front of the main board that is empty on my preamp. That’s all I could see.

It could just be upgraded parts. With my Premier 11, I had Bill Thalmann upgrade mine to the 11A. The only difference was a capacitor or two on each channel to remove some faint noise caused by the LED bias lights.

Here's the inside of my PV14L, taken years ago:

pv14L.jpg (205.47 KiB) Viewed 626 times

I'm not a fan of changing components inside, as it could devalue the unit. If I were going to keep something for a lifetime and/or bought it as a project with the purpose of modifying it, that would not be a problem. But since I won't be keeping mine, It is as unaltered as possible, so I should be able to get the most for it when it sells.

And yes, if they were similar tubes to the Philips/ECG tubes I had when I bought mine, they are indeed microphonic. The new old stock Tung-Sols I tried were very microphonic--if I turned the music up to a middle level (not loud, but not quiet either), I could clearly hear the ringing from the tubes in the music. That completely went away with the M8080s. I tend to think that the M8080/CV4058 is a military tube and built more rugged, which might explain why it isn't microphonic.

[Wildcat]

Plus, and this is a big plus, there’s a remote control for both the volume and to select what input you’re listening to. That’s worth the price of admission all by itself."

I have a weird quirk where, if I'm adjusting the volume and possibly thumb another button, the preamp turns off. I can't duplicate it though. It is also odd that the preamp is in standby, yet the remote has no power button. The remote that came with mine is the cheap-feeling plastic version, not the nice metal version that others got. I may one day get a universal remote that's easier to hold and program it to use with the PV14L.

[admin]

Plus, and this is a big plus, there’s a remote control for both the volume and to select what input you’re listening to. That’s worth the price of admission all by itself."

I have a weird quirk where, if I'm adjusting the volume and possibly thumb another button, the preamp turns off. I can't duplicate it though. It is also odd that the preamp is in standby, yet the remote has no power button. The remote that came with mine is the cheap-feeling plastic version, not the nice metal version that others got. I may one day get a universal remote that's easier to hold and program it to use with the PV14L.

Typically holding the mute button for 2 seconds is the on/off button on the remote. I would at least try that prior to getting a new remote (unless you just want a nicer feeling remote with it being metal).

As for turning off with volume adjustment and hitting another button. That sounds like potential static discharge or grounding issue.

[Wildcat]

Typically holding the mute button for 2 seconds is the on/off button on the remote. I would at least try that prior to getting a new remote (unless you just want a nicer feeling remote with it being metal).

As for turning off with volume adjustment and hitting another button. That sounds like potential static discharge or grounding issue.

I don't remember seeing that in the manual--I just tried it and yep, it turns the preamp on and off. Odd they wouldn't dedicate a button to it though. It's like I found something new!

I think I know what was happening now. I'm betting I might have been holding down the mute button when the preamp turned off, thinking (without looking) that it was the volume button. The DAC has its own volume control so I typically use that instead, especially if I'm over at the rack (it's a knob).

[Joe Appierto]

The CA200 that I have is similar in that holding down the mute button for a few seconds puts it into standby. There is no on/off feature at all short of unplugging the unit from the wall outlet/power conditioner/power strip.

[Wildcat]

Some of my other components have a separate power on/off switch on the rear, and lately I've been turning almost everything off when not using the system. (In fact, I've been busy enough that I haven't used my main system in at least a week now.) I could use the on/off switch on the power conditioner if I needed to. I once looked at how much power the system was using at standby, and let's just say that my LED bulbs in the room, illuminated, used less power than what my system was drawing in standby. We've noticed between a $5 to $10 per month savings on the electric bill from shutting down anything we're not using.

Naturally, that doesn't account for things I forget to shut down. Which happens way more than I care to admit!

I actually unplug everything electronic in the house, except for the network and WiFi, one of the servers, surveillance cameras, etc. when we leave on an extended trip. The networking is tied to a UPS, and the attached NAS has a feature where, if the battery power on the UPS gets low, it initiates a shutdown sequence on the NAS.

[admin]

I think the general consensus is that for high end audio equipment it is best to keep them plugged in all the time. When not in use, they can be in standby mode but should not be completely turned off. Paul McGowan from PS Audio did a little segment on this a few months ago on his youtube channel.

In my system everything stays plugged in and in standby mode when not in use. If I go away for an extended period I will turn it off completely and cut the power on my power conditioner/voltage regulator.

[Wildcat]

As little as I use the system now, leaving it in standby for a week and using it for only 2-3 hours makes no sense for my situation. I figure all the electronics get up to stewing temperature within an hour, so I have no need to leave it in standby 24/7. If there are any sound quality differences between being fully warmed up vs. left on for a week, I'd never hear them anyway--I listen at lower levels now. If I were having one of our audio club meets, or having friends over for listening, for sure it would be fired up and stewing away by late morning.

My measured standby power usage on the system was almost 58 watts. On an average 30-day month, that's 41.76 kW/h consumed. Our average yearly rate (peak, off-peak, winter and summer) works out to $0.172/kWh. So that's $7.18/month just for a handful of components to run in standby all year long, or $86/year. If I add up all the "vampires" in the house (chargers, appliances, etc.) not actually doing anything but being plugged in, it's costing us $21/month. So that adds up to 15-20% of our electric bill going to "vampires" in the house, not performing any function while powered up and standing by.

[admin]

I understand your viewpoint. And I get that nobody wants to spend an extra $100 a year for keeping things on when they are not using it. But I guess the question remains is that if it leads to quicker component failure, then maybe the overall cost of keeping it on may be worth it. I think it's hard to judge. I can't fault people for going either way.

Here is what Paul from PS Audio has to say about it:

https://youtu.be/99t2p_EtoxQ?si=LXdb6IQkP3zlwQ5-

https://youtu.be/BDBa3asBm2I?si=OpSAGuS22g0Nhn9N

[engie3245]

Here's the inside of my PV14L, taken years ago:

pv14L.jpg

You have an S2! That pic matches the S2 pics I’ve seen online.

[Big Dog RJ]

If they've placed in Black coloured resistors, could well be Vishays. But it's bit hard to tell unless you look very closely for the Vishay logo.

Same type of Vishays that have been placed in both my LP monoblocks and CT5 preamp, over half a dozen or so. These offer further transparency and brilliance in soundstage detail, plus further quietness. Really top parts, very high quality and quite pricey. At this level there are no compromises. But like I said, it's hard to say if they're Vishays unless you had a chance to hold one in your hand before installing. These usually come supplied with the "SE Upgrade Kit" that also includes Teflon caps. And comes at a pretty penny... could be between 2-4grand depending on how many upgradeded parts they send in the kit.

Hope it goes well, and those Mullards will sound beautiful.
Cheers, and enjoy those finest tunes.
RJ