Today, over a six hour period, I measured voltages ranging from a low of 122.1 to a high of 123.3 on the dedicated lines in my listening room. My most current measurement was 123.2. I have a total of 5 dedicated duplex outlets feeding my listening room and the voltage measurements have been identical at each outlet. I also measured for stray voltage on ground and that tested at zero for each outlet. My utility company will not do anything to help me because my voltage is within 5% of 120 volts.
I own the Frankensteins and Takatsuki, Elrog, Sophia Royal Princess and Black Treasure 300B tubes.
I don't pretend to have the technical knowledge to participate in this conversation, but am I correct that I should not be using my Takatsuki tubes in the Frankensteins given my high voltage readings? |
I use a Puerpower 1500+ for my whole system with excellent results.
It doesn't restrict dynamics and the sound is much clearer and smoother.
They have a very good product but their customer service isn't the best unfortunately. It's to bad because it really is a great product.
Joe |
George told me today that 122 volts isn't really the limit but with over voltage can easily spike to 125 or higher, which would be a problem.
Sorry if I didn't stress that better.
Joe |
Bill and Al,
Good points. I think I'll just wait for my replacement Elrogs from George and go from there. What's the point in having premium tubes and degrading the sound with a variac.
Charles, |
Al,
I had exactly the same concern regarding variacs. I spent $1K having dedicated lines run to the room, and who knows how much on PCs. Now I'm supposed to run everything through a cheap variac? I'm also concerned about limiting current. Don't really want to throttle down the juice! On the other hand, one of the PS audio regenerators used might be a reasonable investment. I just know that not everyone likes these, especially for power amps. So even that is an expensive experimental question. I much prefer the do nothing option, but I won't be happy if I am buying new 300Bs 6 times a year.
With respect to my nice words, my parents raised me right. Sometimes the children need to remain silent while the adults converse. Its been too long since my college physics course. Electrons are important to organic chemists too, but we are interested in pushing them from one nucleus to another, not pushing them through a bunch of wires and circuits. |
Bill (Brownsfan), thanks very much for the nice words.
Charles, I suppose it would be reasonable to try that experimentally with an inexpensive variac, perhaps purchased used at eBay, but it wouldn't surprise me if the result was degraded sound quality. Due to both the effects on the amp's sonics of the lower voltage and the effects of the variac itself.
Best regards,
-- Al
|
Hi Al,
You raise a valid point regarding the narrow recommended range for AC power.For sake of argument do you believe using a variac and keeping the AC between say 115-120 to go "easier" on the Elrog 300b(to enhance tube life) is reasonable?
Thanks,
Charles, |
I use a PS Audio, P-10 power regenerator for exactly the same reason. The power in my area can range from 117v to 123v depending on the time of day. The P-10 shows you the voltage coming in and the regenerated voltage going to your equipment. It took me a long time to figure out why my system sounded so much different during particular times of day but once I did, it was a game changer.
It's great to know that the Elrogs will be okay in my Franks. Thanks guys!! |
Thanks Al! I'm going to leave this discussion to you guys who actually know something. I will allow you and George to dialogue until a meeting of the informed minds occurs, at which point, I will act accordingly. I just don't want to start burning through 300Bs.
Once again, you are a priceless AG resource Al! |
07-07-15: Brownsfan
My power company will not address the issue unless the voltage is outside of 120 V plus or minus 5%. That is the standard in the USA for household AC, as measured at the service entrance. The upper limit of that range corresponds to 126 volts. With due respect to George, I must admit to some skepticism about the requirement of 122V max. I would expect that the designs of the power supplies in equipment marketed in the USA would in most cases be targeted to supply optimal DC voltages to the tubes and circuits for an AC input of exactly 120V. And I find it hard to believe that an increase of 1.67% from that figure would be the upper limit of acceptability. Also, I don't see how a statement as specific as "over 122V AC is a game changer for these or any other 300B tubes" can be defined in such a universal manner, apparently with applicability to all 300B-based designs, given that I would expect significant variation among different designs in the +/- tolerances of the transformers and other components in their power supplies. Not to mention in how hard the tubes are driven. Best regards, -- Al |
All, my AC measures 122.1 V. I got the same number last week as I did last November, so I am a little concerned regarding tube longevity in my Frankensteins. I did check to verify I have no red dots on the cathodes. My power company will not address the issue unless the voltage is outside of 120 V plus or minus 5%.
I guess there is a silver lining to not having much listening time for the last couple months. Until if figure something out, I can reinsert my Psvane T's so that the Elrogs aren't compromised.
I have followed the thread since its inception, and am most grateful to all those doing the heavy lifting on sorting through this. However, I am uncomfortable allowing the 122. 1 V situation to stand "unrectified." Were I to utilize a variac, I would probably require two due to my AC wiring configuration. Any recommendations on a relatively inexpensive variac? How about using one of the PS audio power plants with the Franks, which would require some limited room rewiring? |
Al and Joe,
Thanks much! These measurement findings do suggest that the Elrog tube should be fine in the Frankenstein amplifier. Al your selected 300b tubes must be vefy rugged to tolerate the parameters in your amplifier and provide the durability and longevity they do I need to measure my wall outlet AC voltage to be sure that it is not excessive.
Charles, |
Hi Charles,
My only knowledge of the 300B operating parameters in my VAC Renaissance 70/70MkIII consists of the values Raquel provided in the thread I quoted from earlier. In which he said that the plate-to-cathode voltage is approximately 430 volts (compared with 484-79 = 405 for the Elrog in this case), with an idle current of approximately 85 to 90 ma (compared with 77 ma for the Elrog in this case). Also, based on those numbers for my amp, 90 ma x 430 volts = 38.7 watts plate dissipation.
The numbers George measured for the Elrog seem to me to be moderate.
Best regards,
-- Al
|
Charles, George said I should have no problem using the tubes in my amps. Yours are older then mine, make sure the cathode resistors are the same and the rest of the values didn't change.
Best,
Joe |
Hi Al,
In your opinion given the values that George measured, do you feel these represent a high stress level on the 300b tube or more of a moderate level? The heat dissipation levels measured by George are higher than the 26 watts that Israel cited for the amplifier. Although 31 W seems well off the maximum of 39 or 40 W dissipation for the 300b. Is the plate voltage similar to your VAC Renaisance?
Thanks,
Charles, |
Excellent info, Joe (& George). That all seems very comfortable relative to the specified "limiting operating conditions for safe operation" of the Elrog tube. (79V/1.025K = 77 ma). And the plate dissipation which can be calculated from those numbers is actually closer to 31 watts rather than 32. Enjoy! Best regards, -- Al |
Ok, here is the information that George emailed me.
Hi Joe,
You can post this data. Be sure to mention that customers of these amplifiers test their AC line voltages(AC Voltmeter). Over 122V AC is a game changer for these or any other 300B tubes. Ideally, in their home they should be have voltages in the 114-122V range. If they have excessive voltage, they should purchase a "variac" as a means of protection for their equipment.
Best,
George
Hello Joe,
Here it is the recent data taken from Friday's testing......
Takatsuki 300B 474V plate 33 watt dissipation
84 V across cathode
Elrog 300B 484V plate 32 watt dissipation
79V across cathode
EML 300BXLS 486V plate 31 watt dissipation
75V across cathode
Psvane 300B 484V plate 30 watt dissipation
74V across cathode
Line voltage 119.4VAC
Cathode resistor value 1.025K ohms
Best,
George
I hope this helps,
Joe |
Thanks Joe
Needless to say I am curious to learn the results.
Charles, |
Ok, George from Tubes,USA came by Friday and took the measurements.
He requested I hold off this information until he lets Elrog know his findings, which I will honor. I'll let everyone know sometime this week.
First he tested all the tubes on his tube tester. They all came back testing excellent.
These are the 300b we used in the Franks:
Elrog
EML XLS
Takatsuki
Psvane HI-FI series (stock tubes that came the amps)
The cathode resistor measured value in my amp was 1.025k
He tested for plate voltage and cathode voltages.
I'll let you know the results once George talks with Elrog.
Joe |
I wonder if a tube radiator (like o ring, or Kryna) helps the matter... |
Thanks Joe, I'm curious to see what he measures with the Frankenstein. |
Hi Crubio,
Not yet, he sent me an email stating maybe in the next few days.
Once he comes I'll post the readings.
Joe
|
Hello,
Snopro, did George ever get a chance to measure your amp?
Thanks,
CR |
This makes buying any amp and not just the franks super important that one knows the actual operating points of that amp so when it comes time to buy tubes one can do so with confidence. Also know the current draw of the tube one is buying and confer with the builder that all will be well when using that tube. High quality output tubes are so expensive this research is necessary and when both tube and amp manufacturer agree that a tube is safe to use one has mitigated one's risk. |
By the way, in the review by Dick Olsher, it states that Franks are easy on 300B and the anode dissipation is only 25W. Strange... |
I've just ordered a pair of Franks and am also worried about tube issues. Not sure if Takatsuki will last long enough. :) |
Okay I see your point and that is a valid question.
Charles, |
Charles,
Not problems but perhaps shortened tube life?
C |
Crubio
Other than the Elrogs I am not aware of any other tube that has been an issue for the Frankenstein amplifiers. Due to its thoriated filament different parameters were necessary for the Elrog 300b that deviate from the Western Electric standard.
Charles, |
As a fellow Coincident Frank mk2 owner, I'm a bit conserved for
My regular EML 300b tubes, I mean, should we consider only
using 300b XL type tubes from now on? |
Thanks Charles,
Maybe they're cheaper too! |
Hi Matthias
Thank you for your help. I called Cary...and the newer version of the 300SEI actually runs 11 watts (they say) and 400V on the Anode - 35 watts ...so if I understand correctly the ER 300b should be able to handle this easily.
Again many thanks
Robert |
Fla,
Based on Matthias's favorable comments you're fine with the standard Elrog ER 300b.
Charles, |
Will do, thanks!
Do I order the originals or wait for the revision? |
Hi Fla,
I have read the article in 6moons and the description on the manufacturer's site. Very nice amp with a lot of effort in details (huge capacitors in HV supply, dedicated heater supplies for each output tube, smart solution for changing the gain, switchable output impedances from 2 to 16ohms).
Very gentle operating conditions...30W dissipation per output tube only...So "Globe Mesh Type" 300B can be used. This tubes don't like stress also. This amp was build for ER300B ;-)
For best results You should order a matched Quad.
Best regards, Matthias |
Mk,
How about Wyetech Sapphire monoblocks?
18wpc parallel 300B SET self-biasing conservatively run.
Will your tubes work here? Would love to try 'em! |
MK,
Thank you so much for your input. You are a positive influence on the Agon, please keep coming back with your valuable input. We all welcome your knowledgable suggestions. We also all need to encourage folks like yourself and Elrog as a company to seek higher levels of advancement in audio. It is great that a modern tube can best NOS. all the best. Rob |
Hi Robert (Rwanda),
I could not find schematics of the Cary 300 SEI...But the description says 15W(!!!) watt per chanel (out of ONE 300B!).
May be, they use class A2 conditions (driving the tubes to positive grid voltage) or they use the absolute maximum operating conditions (450V/80mA) to get this 15W...
If this amps have a bias control and You can regulate the bias to 70-80mA, ER300B could be used successful. But I can not suggest this at the moment.
Best regards, Matthias |
Hi Rob,
You can use ER300B in the AN Kit-1 without problems...
Because it's a kit I think You should have minimum skills at soldering and assambling. Thats why i suggest to add an additional resistor of 100Ohms(min 2W) between the paralled 1.5k Kathode resistors and the heater pin, so You get 850Ohms cathode resistor at all...resulting more gentle operating conditions.
Best regards, Matthias |
Joe, thanks very much for the nice words. And best of luck as you proceed on this issue.
Best regards,
-- Al
|
Almarg,
I forgot to tell you what a great asset you are to this audio community with your technical knowledge and easy to understand answers.
I thank you, Sir
Joe |
Charles,
George at first asked me if I could get the reading. I told him I wasn't really comfortable doing it, so he said he'll do it when he has a chance to come.
That is very nice of him because he isn't to close by.
Joe |
Joe,
I received a message from George this morning asking if I could have someone measure my amplifier's plate voltage. This may have preceded him contacting you. If he can do your Frankenstein himself that's ideal. I also greatly appreciate his efforts to solve this problem. Joe I look forward to seeing your results with George.
Charles, |
I agree that George Lenz has been very helpful here in working toward a solution for those Frankenstein owners who would like to use the Elrog tubes. |
Ok Al, thanks for the tip will do.
Best,
Joe |
Joe, if possible I would suggest that voltage readings be taken both with the Elrogs installed and with the tubes Israel originally supplied installed.
Regards,
-- Al
|
George Lenz gave me a call and asked if he can come over and get the voltage reading across the tubes in my Franks. This way we'll know for sure what the true voltages are.
The Elrog team wants to know and asked George if he can get them.
George is a stand up guy and is making sure that the Elrogs will work reliably in our amps. I commend him for his customer service and dedication.
I'll let everyone know once we get the readings.
Joe
|
Matthias, Thank you for sending the schematic. |
Hi Matthias
Can you tell me how the Elrog tubes will be with my Cary 300 SEI?
Vielen dank,
Robert |
Mathias, what about the Audion Golden Dreams? They are parallel single ended triode (PSET) amps. Thanks...and your help is very much apreciated |
