David's Phase Linear 700B Thread

[laatsch55]

Forgot about fitz43's offer already?? Better jump on that, he was VERY reasonable about it...

 

[Phase Linear Phanatic]

Forgot about fitz43's offer already?? Better jump on that, he was VERY reasonable about it...

You are late to the party Lee. I am in contact as we speak. I only got the amp back last week so I just started to fix the remaining kinks. Work gets in the dang way constantly.

 

[laatsch55]

Yeah, damn work... only party I was ever late to was my own....

 

[Phase Linear Phanatic]

Doug is sending a meter my way. Once I get it installed, and verify the meter is working; we will go from there. As I received the amp back with the right meter DOA. It was bad anyway as we all knew. So I want the thing physically functional first. Then from there we will try to isolate the one and only thing left. The Hum. I am going to try to replace the inter-connects with something higher quality. They have needed it for a long time anyway. Well....that's money. So back to work I go! LOL!

Jerry said there was NO hum when it left. So I need to figure out what's causing it. If and when I get a break from work; I will pull the amp back out again, and hook it up to a PL2000 pre I have in the garage, attached to some tiny bookshelf speakers, and run it on full range with no goofy equalizers or electronic bi-amp crossover filters. Process of elimination there should tell me if it's a component or a speaker or the amp itself. Any other suggestions from Joe or you Lee, that I haven't taken into consideration; I will take too.

This is in no way reflective of the working of the amp however. Everyone should note: After being white oaked, this thing blew the pants right off me! And probably my neighbors, and the cops as they were walking up to my front door! Good thing I have pairs of spare blue jeans! LOL! The sound is amazing! And double the bulk cap reserve for the crazy power I use on the low end is astonishing.

Just because a needle doesn't move, or a hum exists at no volume; has nothing to do with how this amp is working right now. By all regards, it's white oaked folks!

I am highly satisfied with the results. Anything further left in my thread will be about the remaining issues. Not the final sound product. The punch in my chest has proven to me there is NOTHING out there that can beat a WOAPL 700 (series 1) (700B) whatever. ANYTHING white oaked!

 

[laatsch55]

Do you have cable coming into the house?? We've had some members who had problems with hum induced by the cable guy.

 

[laatsch55]

I've had meters go bad during shipping, easy to kill.

 

[Phase Linear Phanatic]

Do you have cable coming into the house?? We've had some members who had problems with hum induced by the cable guy.

That sounds odd in and of itself? Educate me as to how that would introduce noise into the electrical system? We have no cable coming into the house, but I did spend two grand eight months ago, having a cable company run new CAT 6 and cable runs in the walls, in preperation for att uverse we have yet to get? I thought coax was shielded anyway? and we know the pot wire in the B's are shielded? The thing is; I have BOTH the 700B's hooked up to a monster power isolation unit. The rack kind. As the fifty components in my system won't work with a two outlet scenario. Lol! I figured if i had to go the power strip route, better to get a noise filter and use it as a strip. But again; both amps hooked to it and only the WO makes the hum.

Shipping can poop out a VU meter like that? Wow. They are fragile. I just hope the one Doug has will look the same. I'm pretty sure Its all square on the outside, regardless of the VU meters edges on the inside. So we will see.

When Doug's meter arrives, I'll pull the amp back out and run the test I mentioned earlier. Till then, the amp preforms amazingly regardless. Normally id just throw the third spare 700B in its place and be done with the issue. But THIS amps been white oaked AND overhauled; so iiiiiiiiiiiiii don't think that's gonna happen.

Oh. And this might be helpful. The phase linear-fin fan that plugs into the back of the AC outlet on the amp, causes the hum to increase. So I left it unplugged for the time being. The hum is less but still there. So I am not an engineer or electrician by any means....but it seems the AC in the thing is very sensitive to any interference?

I'll get back to you when I have some more cold hard facts.

 

[laatsch55]

Does the WOPL have a 2 prong plug?

 

[Phase Linear Phanatic]

Does the WOPL have a 2 prong plug?

The WOPL has a two prong plug. The non WOPL has a three prong plug. It was the dual primary transformer kind. So maybe they used a three prong in production of those particular amps for some reason? Jerry says he's never seen a gray three prong on an PL before. But I have. My dad has two of them like that. And two that are not. Not sure what Phase was doing there, but the cords look original. Thats even what the original owner of the other 700B told me when I bought it. (Three prong meaning ground Lee)? I assume that's what you are driving at there? I wish they all were like that in the first place. :-/

 

[laatsch55]

If you have a two prong plug pull it out and turn it over and plug it back in, sometimes that works...

 

[Gepetto]

The WOPL has a two prong plug. The non WOPL has a three prong plug. It was the dual primary transformer kind. So maybe they used a three prong in production of those particular amps for some reason? Jerry says he's never seen a gray three prong on an PL before. But I have. My dad has two of them like that. And two that are not. Not sure what Phase was doing there, but the cords look original. Thats even what the original owner of the other 700B told me when I bought it. (Three prong meaning ground Lee)? I assume that's what you are driving at there? I wish they all were like that in the first place. :-/

you cannot have more than one grounded 3 prong plug in your system unless you want ground loops and the associated hum. This is especially true if you have a cable connection (as in cable TV) to any component in your system. If you have a cable connection to a cable box and that cable box has copper audio connections to your system, then you will have hum. Your copper connections from the cable box should be exchanged for an optical, digital TOSLINK connection instead.

If you do not have a decoder in your surround pre-processor to allow this type of connection, there are high quality audio transformer couplers that allow you to break this troublesome hum link and use copper cables instead.

I rely on the TOSLINK connection. You get the benefit of digital meta data transfer to the pre-processor that does not exist if you take the transformer coupled route.

 

[Phase Linear Phanatic]

you cannot have more than one grounded 3 prong plug in your system unless you want ground loops and the associated hum. This is especially true if you have a cable connection (as in cable TV) to any component in your system. If you have a cable connection to a cable box and that cable box has copper audio connections to your system, then you will have hum. Your copper connections from the cable box should be exchanged for an optical, digital TOSLINK connection instead.

If you do not have a decoder in your surround pre-processor to allow this type of connection, there are high quality audio transformer couplers that allow you to break this troublesome hum link and use copper cables instead.

I rely on the TOSLINK connection. You get the benefit of digital meta data transfer to the pre-processor that does not exist if you take the transformer coupled route.

Interesting. Well luckily I have NO components in my rack that are for tv or video. This is strictly an audio component rack. Speaker wires run from the rack accross the fire place over to massive speakers on the other side of the room. My Rotel pre amp, and one PL 700B have three prongs. My Sangeean HD tuner, Pioneer 6-Disc changer, Tech-Pro equalizer, Electronic Bi-amp X-over Filter and second PL 700B all have two prongs. As well as the two pronged Phase Linear fan that was made to plug into the back of the PL 700B. Which we know only accepts two prongs. Note, the Monster Power Isolation unit in the stack has a HUGE 2" thick grounded power cable that plugs into the wall. And the unit has six pairs of standard 120V AC outlets. So at any time, only TWO devices are plugged into the same isolated filter. So on my time delay outlet, I will have the PL 700B three prong, and the WOA PL 700B two prong, on the same isolated outlet in the back of the monster power center. How does this explain why the one 700B has no noise and the other does? These outlets are all isolated from each other? And since there was no Hum before I even began this project, I have to think that it has something to do with what's been done to the inside of the amp? Below is a photo of only and all that's connected in my set-up at the moment. The bi-amp filter is a small box that is behind the amp. So its not seen in the photo. But it's there. This is strictly a 2-channel sound system.

Turning the plug around? Lee............Really? I better return my degree to my college if that's true.

 

[Gepetto]

Interesting. Well luckily I have NO components in my rack that are for tv or video. This is strictly an audio component rack. Speaker wires run from the rack accross the fire place over to massive speakers on the other side of the room. My Rotel pre amp, and one PL 700B have three prongs. My Sangeean HD tuner, Pioneer 6-Disc changer, Tech-Pro equalizer, Electronic Bi-amp X-over Filter and second PL 700B all have two prongs. As well as the two pronged Phase Linear fan that was made to plug into the back of the PL 700B. Which we know only accepts two prongs. Note, the Monster Power Isolation unit in the stack has a HUGE 2" thick grounded power cable that plugs into the wall. And the unit has six pairs of standard 120V AC outlets. So at any time, only TWO devices are plugged into the same isolated filter. So on my time delay outlet, I will have the PL 700B three prong, and the WOA PL 700B two prong, on the same isolated outlet in the back of the monster power center. How does this explain why the one 700B has no noise and the other does? These outlets are all isolated from each other? And since there was no Hum before I even began this project, I have to think that it has something to do with what's been done to the inside of the amp? Below is a photo of only and all that's connected in my set-up at the moment. The bi-amp filter is a small box that is behind the amp. So its not seen in the photo. But it's there. This is strictly a 2-channel sound system.

Turning the plug around? Lee............Really? I better return my degree to my college if that's true.

View attachment 9765 View attachment 9763

Why do you think they are isolated Dave? The monster is just a filter and surge suppressor based on reading the specs. Basically a fancy extension cord.

The AC safety ground cannot be isolated by code even if the AC mains run through a transformer/isolator of some sort.

 

[Gepetto]

I have 3 Crown DC-300's in my upstairs rack Dave.

All three have 3 prong plugs on them. None of my other equipment has 3 prong plugs on it.

If any 2 of the Crowns are plugged into my isolated power bus (I have a Topaz 2.5KVA Ultra-Isolator isolation transformer) with the safety ground attached = hum.

If only a single Crown is plugged into the power bus with the safety ground connected = no hum.

Other 2 DC-300s have cheater plugs attached to defeat the ground loop induced hum.

 

[laatsch55]

120 coming into the house has Line, neutral and ground. At the main breaker panel neutral and ground are treated the same, although with separate bus bars they are connected within that panel. On a branch feeder circuit they are kept separate until they return to the main panel. IF ANY other electrical apparatus is plugged into the same circuit there is a potential for hum based solely on the fact that if your neutral tab is running with the line on the other stuff, then your line is running with their neutral......./

 

[laatsch55]

Also gotta ask the obvious question, is the hummer connected to a pre and is the pre on??

 

[fitz43]

120 coming into the house has Line, neutral and ground. At the main breaker panel neutral and ground are treated the same, although with separate bus bars they are connected within that panel. On a branch feeder circuit they are kept separate until they return to the main panel. IF ANY other electrical apparatus is plugged into the same circuit there is a potential for hum based solely on the fact that if your neutral tab is running with the line on the other stuff, then your line is running with their neutral......./

The reason for polarized receptacles. Large blade and small blade plugs.

 

[Phase Linear Phanatic]

The reason for polarized receptacles. Large blade and small blade plugs.

But don't the Phase Linear two prong amps have two blades of equal size? Pretty sure. And Joe.........your explanation still doesn't explain why the amp had no hum pre-conversion, and does after the fact. Nothing in the set up has changed. As far as the isolated banks are concerned; they are isolated because each set preforms a different function. One set serves as a five second time delay on/off for high current audio devices. Another serves as a simple switched mode on/off audio filter. Another, an always on video filter etc. Separated based on function. Lee I have a pre-amp at the top in that photo. It is three prong and not on any switched or time delayed outlet. You have to manually turn it on first. THEN you turn on the power center, which turns on the disc player and radio tuner. Then the time delay bank kicks in five seconds later and the Phase Linears come on. With hum on the low end 700B only. This process was identical before I ever did anything to it. Now I put the spare 700B I have here on hand, in the WO 700B's place, and bam. No hum on my low end. Same two prongs, same scenario. As I have said before; my instinct would to simply be to let the spare B stay there and have working meters and no hum and be done with the issue. But we have gone too far now. I am totally White Oaked, AND component overhauled. Too much $$ in parts tied up. And a lot of time invested in this project. And man the impact of the conversion can be felt miles away! I can't just have a 70lb. paperweight. Gotta figure this out....................... Doug's meter is on it's way. Let's see what happens next weekend.

-Dave

 

[Phase Linear Phanatic]

I have 3 Crown DC-300's in my upstairs rack Dave.

All three have 3 prong plugs on them. None of my other equipment has 3 prong plugs on it.

If any 2 of the Crowns are plugged into my isolated power bus (I have a Topaz 2.5KVA Ultra-Isolator isolation transformer) with the safety ground attached = hum.

If only a single Crown is plugged into the power bus with the safety ground connected = no hum.

Other 2 DC-300s have cheater plugs attached to defeat the ground loop induced hum.

Wait................. now that I think about what you are saying a little more; Hmmmmm......................... so do you think that the PL700B I acquired for my high end with the three pronged outlet on it, is introducing that hum to my two pronged white oak 700B? I have a cheater plug I could use on it? You think it could be that simple? Could I get that lucky??

 

[laatsch55]

Yeah, once you hear a White Oaked PL 700 you're F*&^%$ for sure. Nothing else will do. Love the headroom, love the sound, love the way my eyeballs vibrate at ----a quote from Dr. Lucitt-----"sublimely insane power levels"...