Ct0517, look, I do not know what krell amp you have or owned, my amp is hard wired straight to the power supply!, not going to any bus bars, there is none!,I myself have seen this inside my amp, and krell also has confirmed this to me!, my amp does NOT consume 30 amps!, it simply spikes over 20 amps, what I have tried to make clear to all of you, I have a 30 amp dedicated electrical line, a 30 amp single pole breaker, and a wpo that is 20 amp's but sustains the amp spikes over 20 amps with no issues, my amp runs smoother, cooler, bigger sound stage, hugely more dynamic, my amp is no longer choked by the 20 amp breaker.
Amp and preamp on same outlet?
Just how much of a no-no is this? ARC goes as far to print in their manual to say to have the amp and preamp on their own circuit. I live in an apt. and I'm forced to have both plugged into the same outlet. Cords just don't reach....How much sound quality is lost by doing this? It sounds great as is, but is there a major detriment to this? I'm curious.
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@Audiolabyrinth thanks for clarifying the costs - that makes sense. jea48, ct0517's tech guy did not work at krell! Well of course not he is Canadian. But he has worked on the Master Krell Ref's. Can everyone working in the service dept at Krell these days say the same ? Now..... I don't "really" care about the answer - just think about it..... Ct0517, look, I do not know what krell amp you have or owned Not sure why not. I show a virtual page. You can see what I have. BTW what speakers are you using with the amp ? I have a huge bag of the old parts! Sometimes a picture is worth a thousand words. After all the public chat forms imo are for learning sharing and a little fun. here is a pic to give the others reading an idea ************************************************** 03-08-15: Mrvordo Thanks for clarifying Mrvordo. MrV and AudioLabyrinth My two rooms are in the basement adjacent to one another. B is closer to the Fuse panel over A the main room. I left a path - removeable ceiling - going from outside Room A, past Room B to the fuse panel for upgrades and changes. If I ever chose to add new line (30amp service), it would be very easy laying new line over the beams. The only costs being the electrician putting in the breaker. Have a nice day. beautiful looking Sunday. Happy Listening. |
Mrvordo, Did you tell Audiolabyrinth it was alright to install a NEMA 5-20R receptacle 125V 20 amp rated receptacle on a 30 amp branch so he could then plug in the NEMA 5-15P 125V 15 amp plug that is connected to a power cord that feeds the Krell 700W @8 ohm, 1400W @4 ohm, 2800W @ 2 ohm, with an up to 6000 Watt power consumption rating per Krell specs of the amp?
03-08-15: MrvordoReally? Curious why didn't Krell just install a 30 amp plug on the power cord to begin with? . Highlights.....
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quote "I believe krell also used the inter power 15 amp plug on my captive power cord because this will not make any difference useing a 30 amp circuit," . . Again for the umpteenth time there is no difference in the contacts or associated current carrying circuit parts of a 20 amp breaker or a 30 amp breaker! ONLY the TM, thermal and magnetic, trip setting are different. Any differences possibly heard could only be because of the contact seating of the contacts in the breaker or possibly the tension contact of the breaker to the bus tie of the bus of the electrical panel. Note the breaker connecting mechanism is made of exactly the same material for both the 20 amp breaker and the 30 amp breaker for that manufacture, model and style number. TRY A DIFFERENT 20 AMP BREAKER! Then listen again for any difference. IF you hear a difference it is all in your head! For those of you that are hell bent on using a 30 amp circuit connected to a 20 amp receptacle in violation of all electrical safety codes why are you limiting yourselves to using a 30 amp breaker? Why not stick a 60 amp breaker in the panel in place of the 30. Hell, better yet, eliminate the bottle neck breaker all together and tie the hot conductor for the branch circuit directly to the HOT bus on the panel. And for even better performance of the Krell amp eliminate all fusing inside the amp. Talk about a bottle neck, can you imagine all the electrons being forced to get into single file to pass through that small little wire inside the fuse. Let them run free.... . |
03-08-15: Jea48 It's about time you came around with some quality audiophile suggestions Jim!! That's how I have things wired up in my home. Get them stupid fuses out of there altogether! I found that a solid copper plug beats any of those fancy audiophile fuses! Also ALL circuit breakers, 20A, 30A, 60A, 100A interfere with the quality of the sound....PERIOD!! I have my hot conductor soldered directly to the hot buss on the panel, just as you suggest (using high purity silver solder of course). This is the ONLY way to go! The sound is much more open, lively and engaging. In fact, I even took it a step further, and tied the panel buss directly to my amps power supply, eliminating silly connectors and outlets!! This is heaven! The sound is so pure you would not believe it!!! Keep up the great advice!! ;^) Cheers, John |
I found that a solid copper plug beats any of those fancy audiophile fuses!Jmcgrogan2- Because they don't draw as much current as that big ol' Krell arcweld...I mean amp...SETs often sound better with an NOS 1909 s vdB Lincoln copper penny than w the copper plug. I find that the difference between that and the 1924 Lincoln copper to be well worth the additional $1500-$2K. Of course, you've got to be very careful inserting the pennies; if you scratch them their value on the Coiniogon drops dramatically. When scratched, they're not work a " plugged" nickel! |
John, you have got a good start. BUT, if you are not using twelve 9s copper plugs at 150,000 square millimeters of conductor area, you can't possibly have any idea what you are missing. No more choking those poor little electrons. BTW, I have heard what appeared to be just a bit of humming, but absolutely no singing. Couldn't carry a tune worth a damn though. Does that count? |
FWIW, I have found that Rectangular Solid Core® SA-OF8N® copper fuse slugs offer the best sound by far, especially when used with their Isolated Floating Shield. Far better than any penny you have ever heard Michael. Cris, your 12 9's plug is no match for my fuse slugs, which Gauge size is 000 = an area of 85 Square mm. I can hear a fly take a wizz on the 3rd chair cellist with my fuse slugs!! |
Jea and Jmcgrogan, I thought you two already knew that you can't teach a pig to sing, and I'm certainly not going to try. I think my post explained everything pretty clearly. If you already know it can't make a difference, then I guess it certainly isn't worth your time to actually try it. For those who are open minded enough to try things like power cords, outlets, dedicated lines, etc., they will actually get to enjoy their systems even more. Those that don't won't. Good listening, M |
03-06-15: Jea48 @Jea48 I received info from Patrick Bresnahan at Krell that these are 50 amp breakers. I provided some info in my previous post about how it works. Cheers |
"Far better than any penny you have ever heard Michael." I beg to differ; the NOS stamped pennies have better imaging and micro-detail than those Far East-sourced OEM cast plugs. It's actually a gnat taking the whizz on the second chair cellist. I can clearly hear the up and down pitch characteristic. For a typical fly, with a much lower incidence of BPH, you have a single steady pitch note. And it's 18" further to the right. |
I have two dedicated lines, but use only one. The benefits and cost of ac filters mean that I can afford only one and seeing to isolating it from vibrations also means use of only one outlet. Years ago I tried to have each mono block on one dedicated outlet. I found the filters were of much greater benefit than separate lines. |
Ct0517, Thank you for taking the time and finding out the rating of the breaker. 50 amp breaker.... 'IF' we are to assume the breaker handle rating of the breaker is 50 amps that could explain the power consumption max rating given in the Krell owner manual. 6000 max. watts / 115Vac = 52.17 amps. IF , The 700CX amp has two 4kva power transformers. 4000VA, watts, / 115 = 34.8 FLA primary amps, secondary fully loaded for each transformer. (For purposes of transformer rating only). Note, this assumes there is not any other current limiting fusing after the load side of the rear panel 50 amp main breaker of the Krell amp for each power transformer primary winding. Secondary fuse protection could/would limit the amount of power that could be drawn from each power transformer as well. The 50 amp rear panel breaker limits the max FLA combined total possible connected load of the two transformers by a little over 80%. 34.8 X 2 = 69.6 X 80% = 55.68. So what else limits the mains 115Vac power for the 700CX amp? The branch circuit breaker in the electrical panel. Though remember the branch circuit is meant to protect the branch circuit wiring not what is connected to it at the wall receptacle. It is the manufacture's responsibility to select the proper NEMA plug for the FLA load for his equipment. If he say the equipment should be connected to a 20 amp circuit then his equipment must not draw more than 16 amps FLA. The plug on the end of the cord shall be a NEMA rated 125V 20 amp plug. PERIOD! So far I have resisted giving any, "what if", happens in this thread concerning the Krell 700CX. So if the branch circuit feeding the amp is 30 amps, what if there is a ground fault event anywhere in the 120Vac power wiring inside the amp, including the hot side fed of a primary winding of one of the 4kva transformers, to the safety equipment grounded metal chassis of the amp? Will the ground contacts of the plug/wall receptacle combo be able to handle the ground fault current that will travel back to the source, the electrical panel? If the receptacle and plug are NEMA 30 amp rated and UL and or CSA Listed then yes the equipment ground contacts of the plug and receptacle will be able to handle the possibly extremely high current the 30 amp breaker can supply until it reacts to the ground fault load current placed on it and hopefully trips open and breaks the ground fault circuit. If it's a NEMA 5-15P plug/5-20R receptacle connection who knows? Not the manufacture of the devices. Not UL or CSA. And I would be willing to bet Krell doesn't know either. . |
I never said that. Pig singing. . |
Edit post, 03-09-15: Jea48.
Quote "Will the ground contacts of the plug/wall receptacle combo be able to handle the ground fault current that will travel back to the source, the electrical panel?" It should have been obvious but I should have included the plug/wall receptacle Hot contact connection as the Hot brach circuit conductor that is connected to the Hot contact of the receptacle is feeding the high current, caused by the ground fault event, back to the source, the electrical panel, through the safety equipment grounding conductor. "Houston, we have ignition!" Also in case it was not clear my load calculations, in the post, were for possible FLA full load of the two 4 KVA power transformers. I have no idea what the actuals loads could be. If Al couldn't figure them out from the Krell specs given, I assure you I can't. I did try to find a wiring diagram for the amp on the net without any luck. 03-09-15: Ct0517 post reminded me again from a previous post of his the rear panel 50 amp breaker has a pair of wires for hard wire remote control of the breaker. Just a guess, and that's all it is, the 50 amp breaker has a shunt trip solenoid that when energized will mechanically trip the breaker open. The shunt trip circuit could be controlled through relay contacts of relays that are controlled from each channel of the amp. This could be part of overload protection for the two power amplifiers of the amp. A wiring diagram of the amp's overcurrent protection would be nice. For those interested, a look inside the Krell 700CX It's just a shame Krell did not put a 30 plug on the end of the power cord to began with. The power of electricity . |
In the "old days" Preamps had switched outlets on the back where you would plug the amps into because the amps did not have a power switch. Some examples from ARC were the SP3A (still one of the best sounding Preamps I have ever heard) and the SP6 etc. So not only was the Amp and Preamp on the same circuit, but the amp was plugged into the Preamp, and I never thought that was detrimental to the sound. Of course that was back in the days before people were sold on $1,000 power cords and $5,000 speaker cables, etc. |
Just an update for Jea48 and others(?) following the Krell amp rear breaker panel value saga here. :^) To backtrack, I tried to be of service to the thread as a messenger. I posted info from an email from Patrick of Krell advising that the breaker panel value on the back of these amps is 50 amps. I was however curious so I contacted Dan D'Agostino. He advised the breaker value for 120v service amps is 20 amps for reasons noted below. Fwiw I use a custom made 20 amp power cord, with the 20 amp dedicated circuit on my Krell amp. I can therefore only recommend that any Krell amp owner with questions, clarify directly with Krell for their specific amp if they are curious. Patrick is a great resource for me, and I would find it awkward (as you can imagine) to approach him about Dan's info. It won't change my personal situation. The emails follow ********************************************************************** Patrick Bresnahan 09/03/2015 To: [email protected] These are 50 amp breakers. Sent: Friday, March 06, 2015 2:36 PM To: Patrick Bresnahan Subject: RE: breaker value on back of amp ? what is the breaker value on the back of my fpb600 or the other high power amps. FPB-700cx ? the Krell stock cord looks like a 15 amp ? and my wall is 20 amp service. is the breaker 15 amp ? ********************************************************************** I asked the same question to Dan D'Agostino From: [email protected] Date: Tue, 10 Mar 2015 17:14:28 -0700 You have very little protection if there was a failure with a 50 amp breaker. If the unit is set for 120 volts the most a standard 120 volt receptacle can safely have is 20 amps. There is no reason for a 50 amp breaker. It is not safe Dan From: [email protected] Date: Tue, 10 Mar 2015 16:27:03 -0700 Hello Chris that amplifier should Have a 20 amp breaker not a 50 |
J_stereo, I had a ARC SP3 along with a Dual 51 and Dual 75. I never even thought of using the switched or unswitched outlets on the back. I don't remember doing any experiments to discourage using them, but perhaps others advised against doing so. But I certainly do remember little concern about power cords, vibrations, EMI or RFI much less ics and speaker wires. My first special speaker wires were from Bob Fulton and I realized that I had used identical wires on my welding rig while in undergraduate days in a material testing lab. |
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Jea48 :^) Electricity scares the hell out of me so I was compelled to post the info. There is no foolery with Electricity. It needs to be done the right way. But ironically the result of this hobby, the music itself, is all about fooling ourselves ? btw - I enjoyed your electricity video especially the power plants. Thinking about it now I find it kind of funny that the closest I came to feeling like I owned my own standlone powerplant, was with these OTL's The speakers could be disconnected and others reconnected at any time without powering off the monoblocks. They used horizontal sweep tubes. 600 watts at idle just like a 50 inch plasma tv according to the manufacturer. No TV in this room so I kind of justified things in my mind. Almost felt like the speakers were connected directly into the wall outlets. In memory now, I no longer own them, they were like driving a 911 but you could only use first gear. They were designed around the needs of Acoustats. Issues developed with consistency and reliability. Cheers |
