Ok, so basically this is all for "experimentation purposes". That's cool. It just kind of sounded like you were trying to work out some inherent flaw in the sound setup, so that's why I was confused. I totally support you working and messing with the sound for the fun of it.... You certainly have the equipment to do that kind of stuff which is nice. I'm more of a typical audiophile, so you won't find things like equalizers in my system. Not arguing for one being better than the other, just different. But that's cool, everybody has different tastes and I respect that.

Messing with it that is what I’m doing with theatrical ALIENS right now. When the drop ship is in the atmosphere getting ready to land the interior has neat overhead air rushing sound that is placed over the seating. When switching back to standard surround the sound is kinder of heard but when passed though the CP45 the stereo surrounds have new dimension. Give a try no need to keep spending hundreds on new AVR/AVP to extend on the sound plenty of cheaper ways around.

I like how the LCR goes from the foggy dialogue track occasionally with the rapid gunfire attack on the ALIENS, particularly when Hudson buys it, when one of the sneaky ALIENS bursts though the floor LOL and grabs him, pulls him down. You want some of this? F%ck you! Ahgggggghhhhh. The dialogue is heard on the L/R during some moments of the mix. The effects are still a 6track Dolby Stereo classic on this, not dated film.

I like it when Burke turns around and the ALIEN standing behind him, the on-screen hiss aggghhh then hisses over LCR then and as camera angle switches around the sound of the ALIEN, is heard all-around. ahhhh hissss splat, gulp!

The usual side wall surrounds are heard precisely I wonder what effects modules the mixers at Pinewood had fitted in the console as the film as cool state of the art Dolby mix.

Whew that was a lot of hard work unbolting the other Dolby CP45 and so far so good the Dolby CP45 is running okay. I’ll keep it racked up and run it though and if all goes smoothly I keep this one racked up.

I’ve aligned the Dolby EX with my trusty dts music/demo disc (track 14 all-channels) wideband pink noise.

Using the TrueRTA 1/3 SPL meter to measure the sound pressure and check frequency response as well as aligning format 61 AUX/non-sync 2 which I use for standard mono/stereo surrounds and format 60 non-sync 1 Dolby pro-logic for EX use at the press of button. As well as checking levels a double time over with the Dolby CP45 own pink noise to trim up the levels LCR including the overhead surround (as I don’t have a pink noise disc with outer-phase signal).

I’m so tempted to wire in the Sony DFP-D3000 as its been weeks now, still got get a old pc to run its set-up, but I can still wire it up and use the AUX2 8channel input. Only other thing holding me back is the rack ears. I have some 3U rack ears expect the mounting holes on the side don’t line up. I’ve been in contact with another seller that has universal 3U rack ears that I’ll buy soon at cheap price.








Also removed the Cat-515 from the other existing CP45 and placed that on the one now racked.

Saw a nice CP65 with all the cards including SR-type the price is not cheap enough, seems like I'll have to keep an eye out for the Cat-300 or 350.

So it looks like one of the tubes in my Conrad Johnson PV-12 is going bad. I noticed a slight audible "shhh" sound and I called up Conrad Johnson. They suggested I try swapping the tubes to see if the sound changes as it could be a tube nearing the end of its life. Sure enough, swapping the tube made the sound go away. So I ordered a replacement tube which hopefully will be shipped out tomorrow. I'll swap it out as soon as I get it and report back.

Here are some pictures of the PV-12:

looks like the one on the right is a little darker.
love those long stems on the potentiometers / selectors

Once I get the new tube I will be able to tell which one was bad. With vacuum tubes sometimes a clean looking tube will be broken, and some rinky dink old tube will be just fine. I guess I'll just have to wait and see until the new one arrives.

What’s the cost of the valve/tubes? How was it you, were able to hear this "shhh" like sound have you experienced this before?


I got a similar snag with my Kenwood KRF-X9050D that only serves as four-zone surround amp. The relay in the AVR seems to have serious dry-joint that needs soldering as it keeps tripping out the amps and needs a bang on the side to wake it up.

Well I’ve got my eye on some new Behringer PA amps that will only take up 1U frame which I plan to use for HF horns and 2U frame units for LF LCR sub bass extension, surrounds and large model for LFE.1.

Still I need someone to help me to lift all the other amps and processors up a little bit so I can slip the Kenwood out and get soldering. The dry joint has shorted out the centre channel so I can’t use that for overhead matrix surround only the left/right front and rear works. If I bang it hard enough it will wake up which is why I know its dry-joint. Most people would dump it not realizing its simple thing that can be repaired.

I've only just sussed out why my sub bass extension for left/right when playing only in stereo seems soft on sub bass extension though the mixer. When fading down one of the sliders the bass/sub goes deep and louder so ether I solder one of the wires on the back of the CP65 with hot wire on cold or its something else that I have to check, not a big deal to sort out, it must have been when it was hot weather a few months ago when I re-wired the back for the CP45 EX mode?

Edit: I checked though format 10 and back to format 60 where the lows out from LCR to the sub is fine I even formatted Cat443 from 2.4 to standard to check the bass on left and right as it switches off the centre channel and only leaves the surrounds active.

So I know its nothing to do with wiring on the back of the CP65.

I checked some music in format 10 with AVR set to stereo mode 2 channel and opened the sound menu settings on the AVR and changed one of the distance settings that increased the bass output to the smaller JBL sub. Its got me confused and thinking as I must have taken soemthing for granted so I have to double check to trace the snag.

Edit:

So far I have checked my B-chain and since I have cat that likes prowling around and chewing on wires I suspect my Sooty has some answering to do as all was fine with format 10 day before yesterday. I caught the little bugger having a sly, chew last week on the mains cable. What a pity he didn’t bite right though it, then he’ll know not to go poking his, little nose in places that I have told him, to leave alone!

I’ve removed cat card 242 to check if its the card at fault and all seems well expect the trim levels have been sent defiantly weeks ago months ago without any snags. So ether my cat has been getting smart (while I sleep) and having a sneak around at the back of the rack, but I can’t see how its not wide enough for him.

Maybe solar flares have something to do with this, after-all its 2012 and I have nothing but Gremlins on and off over the months, yeah the only Gremlin I have is my cat.

Last week I noticed the electricity voltage dropped twice during the day and nothing to do with what I have wired up otherwise the circuit breakers will be going every time I power up.

I noticed the drop in voltage once during late afternoon and again around early evening also there's going to be thunder storm late this, week.

The tube replacement cost $40. The preamp is over 10 years old so I'm not surprised that the tube started to go (probably should have been replaced long ago). I spoke with the technician at Conrad Johnson and he suggested I switch the two tubes as that would confirm that the tube is bad vs other electronics in the preamp. Sure enough it immediately changed with switching the tubes. The nice thing about buying better quality electronics is they tend to last (and keep their value). Replacing tubes is needed and recommended every 1500-3000 hours of on-time, so this device was probably well past that.

Huh, 3000 hours just a little bit more than what my project lamps time is 2000 hours normal 4000 hours on lower or slower fan speed.

Well I’ve now spent just close to over sweating 2 hours to suss out what the snag is?
I’ve ruled out fault with mixer I tested it with direct 100Hz sine wave and output feed to TrueRTA and all sliders sum the signal up.

So ether something is up with CP65 but I can’t see what I missed as complicated as it is to wire up I tested LCR with ECM8000 microphone between stage channels and signal sums up on the TrueRTA.

The signal tested from the line out from mixer to pc via RCA to 3.5mm phone jack and adjusting the sliders each to equal level the phase seems out with LCR if of the sliders is faded the level will increase and placing the slider back to equal level cancels out or reduces the sine wave 100Hz.

I’m going to re-wire and see what could be the possible fault. I swear that cat of mine gets smarter by the day, just like Toy Story the Toys come alive when humans are not around, or when I sleep my cat gets 200 IQ and starts re-wiring my CP65.

I can see myself at the back of the rack for the next 6 or more hours.

I'm triple checking phasing for summed signal over speakers with mic between. I think 2012 f$R&*king sucks! The weather has been sh!t for weeks now not that I care for it, but its been really pants lately.

If you think the problem is that the cat may have chewed a wire, maybe it's easier to just pull out a simple multimeter and just test each wire for conduction. If the wire is broken, it will tell you that there is no contact. You can probably check every wire in your system in about 20 minutes. Let us know what happened when you get to the bottom of it!

I have multi-meter to check if wires, are broken. I have seen what was done wrong and it can happen to anyone. The left channel input on the CP65 was wired (+ on -) rather than (+ onto + and - onto -). Yeah its very tight space I have at the back as I have cinema seats that limit as to how far I can pull the racks out. Plus I have health condition and my legs are now sore from crunching down at the back for sodden 3 hours!

It didn't occur to me that the wiring was the input all the other inputs are wired (+ to + and – to -) Its not your average RCA or HDMI kook up.

Well I’m glad that is now sorted I have to re-solder the wires back to the LCR to get some sub bass extension back on the mixer. Your probably still wondering how all this, gear is wired up. You realize how much I’m sweating from just being at the back? Its enough for me to change my t-shirt and take a bath afterwards. I’m so done in. Furthermore the CP45 is in the way and it, takes nimble small fingers poking around at the back.

I can’t sodden wait to get that cheap multi stand cable and do it all fresh (one step at a time). I have small touch that I have to hold in my mouth as its rather hard to see. I have to hold it sometimes in my mouth when soldering and that is not easy to do while trying not to burn myself.

you can also get a tube tester to see which are bad, since you do have a lot of gear that uses tubes it may be worth it.
considering tubes are that much, also there is a place on the internet that sells tubes JJ's i believe, they sell high end
for guitar gear, so you may want to check them out?

tube testers are only about 50-80 bucks on the bay.
and i didn't think there was a time of when you should replace tubes, other than when they go bad like light bulbs or
lose their seal.

i've heard of guitar players using amps with tubes that are still original from the 50s, and i've also heard about
others from the mid 80s that have to replace them often.

I considered doing that but for much of my tube equipment I actually already have a 2nd set of tubes, so if something seems to be going wrong, I have others to simply switch out and diagnose the problem. Even with this one, it was pretty easy to diagnose by swapping tubes. Come to think of it, I am starting to acquire a significant amount of tube equipment so perhaps looking into a tube tester would be a good idea....

How many hours do you have the amps ON for? Do you have timer clock or log book to note the amp tube time. You said 3000 hours max? That's still a fair amount of time. $40.00 for tubes that's not bad I thought they were expensive or do you have cheap model?

I don't use a timer. Perhaps I should. The 3000 hours is just a recommend number. With tubes it's highly variable. There are tubes that die out quick, and then some people are using tubes made in the 1950's and they're still good. I was actually surprised by the low price as well. I ordered it directly from Conrad Johnson so I didn't go cheap. Conrad Johnson is a good company in my experience. Their equipment is expensive but if there is any problem they really try to help you out and don't try to screw you over later. I think this is why people keep going back (I have bought 3 CJ products already).

Was it a genuine tube or a good after-market tube? Or has the price come down or is someone doing the tubes at a best low price to keep punters happy?

The lamp for my projector has timer as most do I gather it also has warning LED that will alert me when its nearing its end and for getting on 4 years its had almost very little use and I like to buy a new projector. The lamps for mine are around £75.00 or so now and used to be £250.00 which is a little more than I paid for it second hand.

So how many years you been with Tube amps I rather like transistor and my oldest is the Marnatz 1050 and 1030 that are still running and only need pot or slider changes other than that the amps are still playing fine for over 30 years, yet my Kenwood AVR seems to be having snags that I'll get around to fixing soon...

How many tube amps do you run or do you only use one for stereo listening and the AVR to power or tube amps connected to the pre-outputs?

My projector has a timer on it as well. They don't do timers on high end audio equipment running on tubes. It's a very different market. I also got a free extra projector lamp when I bought my projector which was nice (I forgot to mention that previously).

I have been using tube amps for a few years now. It truly is a very pleasing sound. I use transistor for my movie watching, but I have a completely separate two channel setup (isolated 7.2 setup for movies, and 2 channel setup for music). There are multiple tube components in this two channel setup. I have a tube based phono preamp, tube preamp, and tube input stage amplifier.

That is something I have noticed with some projectors being sold on eBay that comes with free lamp and most lamps offer on some models 6K hours worth which can last several years, if used wisely.

Well get cheap countdown clock that can be programmed or a log book to log the tube hours or simple reminder on some white paper Tube amp should be running out in 2016? How often do you use it over the AVR transistor amps?
I use my amps like no bodies business I’ve had them as long as 4 days and the heat they throw out is like having the gas central heating radiator ON in the summertime! Every time I walk in the living room the heat hits me and I keep checking if the heater is turned ON by touching it with my hand.

I’m still listening to that Kim Wilde video 10 hours or is it 11 hours now...over and over its serious non-sync home cinema music. I’m going to try and play it right out to the end of the day or until I’m blue in the face with it.

i like tube amps but don't really have the funds to deal with the tubes etc.
i had a nice guitar tube amp but decided to sell it since i never really used it, and cost for all tube replacement would be
200 so it had to go.

there are forums just for tubes, but that's all i know, don't need to know about more stuff to collect

Well tube was used for cinemas donkey years ago...before replaced with transistors amps.

Funny how things turn around. The top audiophile manufactures of amps now use tubes and they are the most expensive.