hehe, no, it sounded like an acceptance speech, but he forgot to thank the academy
Have you seen Mahoney's acceptance speech out of Police Academy?
Ok I promise I won't go off topic anymore
Nice work EUVL and merry men. I am looking forward to seeing the final product and will probably purchase a pair of PCBs. I have 6 complete F5 amp kits with Daniels mini-boards waiting for me to work on, so your F5X work is timely. I also have two 16" long pieces of Russell Boss 's 10.5" tall heat sinks which make the Conrad 151's look pretty wimpy. You CANNOT have too much heat sink area for a Pass amp.
Questions - what is the Class A power limit of the F5X with 16V rails and 2A bias vs. simply running two F5 out of phase at 24V rails and 1.2A bias ? What is the Class AB power limit of the same two sets of amps ? Is there not a trade of Class AB power limit vs Class A power limit ? Most important - which one has the best sounding "first watt ?"
Questions - what is the Class A power limit of the F5X with 16V rails and 2A bias vs. simply running two F5 out of phase at 24V rails and 1.2A bias ? What is the Class AB power limit of the same two sets of amps ? Is there not a trade of Class AB power limit vs Class A power limit ? Most important - which one has the best sounding "first watt ?"
The F5X is designed to peak output at 24V 4A (i.e. to 6 ohm), which works out to 48W sine.
I never intend to run my circuits at Class AB so I have not thought about Class AB power.
That is not to say it does not work in Class AB (for say a 2R load). Just that I have no numbers.
The rest are subjective questions which I shall pass.
And if you insist then I shall always say Nelson's solution is the best.
It is his forum afterall.
Best regards,
Patrick
I never intend to run my circuits at Class AB so I have not thought about Class AB power.
That is not to say it does not work in Class AB (for say a 2R load). Just that I have no numbers.
The rest are subjective questions which I shall pass.
And if you insist then I shall always say Nelson's solution is the best.
It is his forum afterall.
Best regards,
Patrick
Perhaps an update since it's turned quiet.
1. I have checked the latest F5X PCB and there are a couple of small things need updating. Waiting for bksabath to respond but have not herad from him for quite a few days. Hope all is well.
2. The two other guys are working hard on the control / protection / auxiliary PSU boards and the regulator / capacitor boards. I have checked through the schematics for one of them and discussed the component layout, so we are perhaps two weeks from first draft.
3. Drawings sent for cost estimations and hope to be able to give a number to Variac within a week.
Thanks to all working very hard behind the scene,
Patrick
1. I have checked the latest F5X PCB and there are a couple of small things need updating. Waiting for bksabath to respond but have not herad from him for quite a few days. Hope all is well.
2. The two other guys are working hard on the control / protection / auxiliary PSU boards and the regulator / capacitor boards. I have checked through the schematics for one of them and discussed the component layout, so we are perhaps two weeks from first draft.
3. Drawings sent for cost estimations and hope to be able to give a number to Variac within a week.
Thanks to all working very hard behind the scene,
Patrick
My left hand diodes have been Hacking a lot
Well as a normal human been should guess one get tired off put downs sarcasm and patronising.
Here on this tread and others as well as on Emails.
Was not going to reply but I feel that it is right for the other members to know.
I am not allowed to write my standard response in Queen English so the American translation will have to do…
Have a Nice Day
Ps don’t bother to report this post I already did (may even get same points)
Al
Well as a normal human been should guess one get tired off put downs sarcasm and patronising.
Here on this tread and others as well as on Emails.
Was not going to reply but I feel that it is right for the other members to know.
I am not allowed to write my standard response in Queen English so the American translation will have to do…
Have a Nice Day
Ps don’t bother to report this post I already did (may even get same points)
Al
It is obvious that even though thanh and I have tried our best to accommodate any cultural differences and have taken care and time to explain reasons behind our recommendation for changes as well as any phrases we have used which had a different meaning to you than to us, we have failed to do this to your satisfaction, and I am truely sorry that we did not succeed.
I shall send the current Gerber files to Variac to let him decide whether he wish to use them as they are, and in the meantime to contact the other PCB helpers and see if one of them would take over in case Variac thinks it is necessary to do so. More I cannot offer.
Best regards,
Patrick
I shall send the current Gerber files to Variac to let him decide whether he wish to use them as they are, and in the meantime to contact the other PCB helpers and see if one of them would take over in case Variac thinks it is necessary to do so. More I cannot offer.
Best regards,
Patrick
the Conrad 151's look pretty wimpy. You CANNOT have too much heat sink area for a Pass amp.
What is the Class AB power limit of the same two sets of amps ?
Agree with you 100% on the first one that’s the reason of me asking about cooper spreader plates.
And also the reason I was looking for larger heat sinks see my “Huge heat sink post”
In regard to 2 to keep this simple and exposing myself to the usual…
(sorry if it is basic you probably know more than me but I dont know what you know but I know that I dont know... Or someting like that)
The Supply Voltage and the Bias current on the given load limit the class A power. (X2 on the balanced version)
By given load take in to account the Impedance of your speakers this is normally 8 or 4 ohms nominal.
But “nominal” does not really means much as capacitance came in to play and as current and Voltage are out of phase you get same more out of it.
Class AB is limited by the supply voltage & by how close the circuit can go to it (Is very difficult to swing a circuit to the supply rail) over your load.
The crunch question is how much power do you really need?
To keep this simple and exposing myself to the usual…
Play one of your favourite tracks on what you got at your laud volume setting.
(I set mine to the She is gone out shopping position)
Ad a bit more (now dB comes in to play is a pain to measure but again To keep this simple and exposing myself to the usual…3 dB is normally felt as 2 times as laud)
Measure the voltage at the speaker’s terminals.(give you same head room)
I vas quite surprise to see only 8.29 volts peak when I did this.
So maybe sound quality is more important than Watt.
Can it swing this whitout cliping is the question.
Papa said, “They sound better with more current”
Which bring as back to point 1 more current more heath.
I must admit that running 2 Amps is better than 1.3 probably that’s why in this case the supply is down to 16 V
Personally as on point 1 and because is difficult to Judge the performance of the heat sink If you need more power (and you don’t like to ear the class AB cross over distortion) crank up the voltage then reduce it if the heat sink cant cope.
I am going to start with 27 V rails but the mossfet will be further apart and not one the same vertical line and there are going to be 3 on each quadrant.
But this is only my opinion and it aint worth much.
Besides if the copper does no do the trick and I feel that I don’t want to compromise with the current maybe gold heath spreaders will have to come in to play.
Fans and water-cooling are also possible.
I just wish I were in Australia where water-cooling came for free (just a couple of T and same cooper pipe connected to the Air con).
This is DIY and I like it this way…
Al
What is the Class AB power limit of the same two sets of amps ?
Agree with you 100% on the first one that’s the reason of me asking about cooper spreader plates.
And also the reason I was looking for larger heat sinks see my “Huge heat sink post”
In regard to 2 to keep this simple and exposing myself to the usual…
(sorry if it is basic you probably know more than me but I dont know what you know but I know that I dont know... Or someting like that)
The Supply Voltage and the Bias current on the given load limit the class A power. (X2 on the balanced version)
By given load take in to account the Impedance of your speakers this is normally 8 or 4 ohms nominal.
But “nominal” does not really means much as capacitance came in to play and as current and Voltage are out of phase you get same more out of it.
Class AB is limited by the supply voltage & by how close the circuit can go to it (Is very difficult to swing a circuit to the supply rail) over your load.
The crunch question is how much power do you really need?
To keep this simple and exposing myself to the usual…
Play one of your favourite tracks on what you got at your laud volume setting.
(I set mine to the She is gone out shopping position)
Ad a bit more (now dB comes in to play is a pain to measure but again To keep this simple and exposing myself to the usual…3 dB is normally felt as 2 times as laud)
Measure the voltage at the speaker’s terminals.(give you same head room)
I vas quite surprise to see only 8.29 volts peak when I did this.
So maybe sound quality is more important than Watt.
Can it swing this whitout cliping is the question.
Papa said, “They sound better with more current”
Which bring as back to point 1 more current more heath.
I must admit that running 2 Amps is better than 1.3 probably that’s why in this case the supply is down to 16 V
Personally as on point 1 and because is difficult to Judge the performance of the heat sink If you need more power (and you don’t like to ear the class AB cross over distortion) crank up the voltage then reduce it if the heat sink cant cope.
I am going to start with 27 V rails but the mossfet will be further apart and not one the same vertical line and there are going to be 3 on each quadrant.
But this is only my opinion and it aint worth much.
Besides if the copper does no do the trick and I feel that I don’t want to compromise with the current maybe gold heath spreaders will have to come in to play.
Fans and water-cooling are also possible.
I just wish I were in Australia where water-cooling came for free (just a couple of T and same cooper pipe connected to the Air con).
This is DIY and I like it this way…
Al
Supose my PCB work came in to question as I am shure it will so premature and out of topic so sorry to you all.
I did transfer an ACAD drawings in to A PCB format.
That was esactley as the ACAD drawing I got to the point that I had to work on 1/48
grid (some may know this in Tau to give you the Idea) becase ACAD does not know the component size.
When I coreted the fact that the original silk screen was larger than the board.
I used the PCB components and automatically the program placed Q1 and such numbers on the silk screen and got a telling off.
This and other comments made me react and then to decide to Ingnore any further contact whit Patrick.
If I am back is only because of his "I hope he is Well" remark.
Now what you don't see his the Email whit a list of mistakes that need to be corected those where on the Original design that I don't have any longher as agreed once terminated my funcion it was deleted.
PS. strange how he can see a 5 tau Q1 text but it takes 3 weeks later to spot a fet wrong way around and a list of other bubus not to mention a silk screen larger than the board
If any help is needed I am still here so dont esitate to ask.
If you need to take over "my Function"again just ask if you need my files I may be able to recover them now you know what the score is. so good luck.
In regard to "My cultural differencies" tanks to the ones that fell the same as me and sent PM in support.
To keep this in topic I will not use that PCB as it is currently there are same serius issues with it but did not dare mention this before.
AL
I did transfer an ACAD drawings in to A PCB format.
That was esactley as the ACAD drawing I got to the point that I had to work on 1/48
grid (some may know this in Tau to give you the Idea) becase ACAD does not know the component size.
When I coreted the fact that the original silk screen was larger than the board.
I used the PCB components and automatically the program placed Q1 and such numbers on the silk screen and got a telling off.
This and other comments made me react and then to decide to Ingnore any further contact whit Patrick.
If I am back is only because of his "I hope he is Well" remark.
Now what you don't see his the Email whit a list of mistakes that need to be corected those where on the Original design that I don't have any longher as agreed once terminated my funcion it was deleted.
PS. strange how he can see a 5 tau Q1 text but it takes 3 weeks later to spot a fet wrong way around and a list of other bubus not to mention a silk screen larger than the board
If any help is needed I am still here so dont esitate to ask.
If you need to take over "my Function"again just ask if you need my files I may be able to recover them now you know what the score is. so good luck.
In regard to "My cultural differencies" tanks to the ones that fell the same as me and sent PM in support.
To keep this in topic I will not use that PCB as it is currently there are same serius issues with it but did not dare mention this before.
AL
The layout I have in ACAD is for my personal use and not suited for automatic transfer to some Gerber format. My apologies that I did not make it clear up front.
This layout have been built 4 times, and they are in working order. This is also the only thing that I promised, that I make my layout available to DIYA. How perfect it is of whether it is suitable for public use is for Variac to decide.
I shall try my best to make sure that what I send to Variac is functional and error free. Whether he would like to do a proto test or not is entirely his decision.
I made a promise and I shall keep to it until my task is completed.
Best regards,
Patrick
This layout have been built 4 times, and they are in working order. This is also the only thing that I promised, that I make my layout available to DIYA. How perfect it is of whether it is suitable for public use is for Variac to decide.
I shall try my best to make sure that what I send to Variac is functional and error free. Whether he would like to do a proto test or not is entirely his decision.
I made a promise and I shall keep to it until my task is completed.
Best regards,
Patrick
Decision, decisions, decisions
Bksabath, I think you are getting to my point.....the one thing you know you probably don't want to do is allow the thing to clip every five seconds for your load....my dilemma is deciding whether pure Class A that clips (a little) on uncompressed digital audio (SACD, Blu-Ray, etc.) is better or worse than a "rich AB" amp that doesn't clip at the same perceived loudness level.
I don't know the answer to this, but I do know that big heat sinks dissipate more power and keep the junction temperatures further from the MOSFET design limits, and that bias current is a LOT easier to change than rail voltage. I also know if I rectify to 24V rails, I can get to 16V rails with a little more complexity, but it is damn near impossible to go the other way around.
Let me know how long those little suckers last with 2A bias and 24V rails....my guess is not as long as Beethoven's 9th Symphony.
Bksabath, I think you are getting to my point.....the one thing you know you probably don't want to do is allow the thing to clip every five seconds for your load....my dilemma is deciding whether pure Class A that clips (a little) on uncompressed digital audio (SACD, Blu-Ray, etc.) is better or worse than a "rich AB" amp that doesn't clip at the same perceived loudness level.
I don't know the answer to this, but I do know that big heat sinks dissipate more power and keep the junction temperatures further from the MOSFET design limits, and that bias current is a LOT easier to change than rail voltage. I also know if I rectify to 24V rails, I can get to 16V rails with a little more complexity, but it is damn near impossible to go the other way around.
Let me know how long those little suckers last with 2A bias and 24V rails....my guess is not as long as Beethoven's 9th Symphony.
DCbingaman
Agree on the basic principles.
The point at which it will clip is down to how laud you can get.
I started posting on those forums asking exactly the same questions
Once I got down to measuring the levels I was quite surprised to see that 8.5 volts where enough to keep me happy. (Or maybe my ears where giving up and found the noise coming out of the Kandy to much to bear)
I don’t think you should have any problems unless your room is really big or your speakers are low efficiency.
I have a pair of Polk LSi 15 and they are rated at 87 dB and a pain to drive
I tried the Sugden 25 W and I did like the sound of it but it did not really made the grade on the She is gone out shopping volume setting.
I have also tried the 250W integrated Krell and did not like the sound of it.
My plan was to start with the F5 end then to work my way up to the A75
Burning amp 1 and 2 are on the pipeline.
I think that the balanced F5 will be plenty but as Papa said same where you don’t want to do 55 with the pedal to the floor. (Sorry if I misquote writing on the Fly)
I understand that you may have doubts on what Papa babies can do jus consider that he is one of the most respected masters of the trade I found the articles on the First Watt site inspiring if still not convinced is worth a 250 miles trip to go and listen to one of his products I did just that.
Maybe a dealer is just around the corner from you…
In regard to the heat sinks you probably have seen the nice pictures with the lovely colours on it take same time and have a look at the scale on the right hand side
One goes up to 63 C the other to 61 the other I cant remember
What’s red on one should really be yellow there is load of it going on and you are not the first one that is wondering.
Just see the slagin off I got for the push buttons and how the tone changed after someone else interceded
I got 2 300 X 400 X 83 heat sinks coming in next week see my post huge heat sinks
I will also use cooper heat spreaders and 12 Mossfet. And fans if I have to.
My trafos are custom jobs 1000VA 24 V with a tap at 20 V I have not tried any of it so far but be assured that once I do it will al be in the open and also be assured that WE don’t have any intention to sell any of it or to dole out the information WE have only if WE got to
Copy of the quote from the heat sink manufacturer is posted for all to see.
As you say is easy enough to go from 24V to 16 and if it sound better it will also is easy enough to drop the Bias but Papa said that they sound better at higher Bias.
I don’t think I will use that PCB on one of Papa design and this is pretty sure thing
I don’t really know what would be best, my opinion don’t count for much as I am New here and I don’t have any Alphabet behind my name.
Al I can do is going to build one and carry on making it better and better
This is DIY and I love it I got 100 each of the Fairchild dudas and someone else is taking care of the protection circuit if it blows it blows hopefuly while she is out.
Al
PS Love the 9Th but is all down to who and where and whit?
You talk about this kind of music must also say whos and where.
PSS We Take upon ourselves the right not to brag about what kind of qualification we have. (Loads of svet and Blood in the trade since 1976 )
Don’t you Just love the way the WE form is used?
Agree on the basic principles.
The point at which it will clip is down to how laud you can get.
I started posting on those forums asking exactly the same questions
Once I got down to measuring the levels I was quite surprised to see that 8.5 volts where enough to keep me happy. (Or maybe my ears where giving up and found the noise coming out of the Kandy to much to bear)
I don’t think you should have any problems unless your room is really big or your speakers are low efficiency.
I have a pair of Polk LSi 15 and they are rated at 87 dB and a pain to drive
I tried the Sugden 25 W and I did like the sound of it but it did not really made the grade on the She is gone out shopping volume setting.
I have also tried the 250W integrated Krell and did not like the sound of it.
My plan was to start with the F5 end then to work my way up to the A75
Burning amp 1 and 2 are on the pipeline.
I think that the balanced F5 will be plenty but as Papa said same where you don’t want to do 55 with the pedal to the floor. (Sorry if I misquote writing on the Fly)
I understand that you may have doubts on what Papa babies can do jus consider that he is one of the most respected masters of the trade I found the articles on the First Watt site inspiring if still not convinced is worth a 250 miles trip to go and listen to one of his products I did just that.
Maybe a dealer is just around the corner from you…
In regard to the heat sinks you probably have seen the nice pictures with the lovely colours on it take same time and have a look at the scale on the right hand side
One goes up to 63 C the other to 61 the other I cant remember
What’s red on one should really be yellow there is load of it going on and you are not the first one that is wondering.
Just see the slagin off I got for the push buttons and how the tone changed after someone else interceded
I got 2 300 X 400 X 83 heat sinks coming in next week see my post huge heat sinks
I will also use cooper heat spreaders and 12 Mossfet. And fans if I have to.
My trafos are custom jobs 1000VA 24 V with a tap at 20 V I have not tried any of it so far but be assured that once I do it will al be in the open and also be assured that WE don’t have any intention to sell any of it or to dole out the information WE have only if WE got to
Copy of the quote from the heat sink manufacturer is posted for all to see.
As you say is easy enough to go from 24V to 16 and if it sound better it will also is easy enough to drop the Bias but Papa said that they sound better at higher Bias.
I don’t think I will use that PCB on one of Papa design and this is pretty sure thing
I don’t really know what would be best, my opinion don’t count for much as I am New here and I don’t have any Alphabet behind my name.
Al I can do is going to build one and carry on making it better and better
This is DIY and I love it I got 100 each of the Fairchild dudas and someone else is taking care of the protection circuit if it blows it blows hopefuly while she is out.
Al
PS Love the 9Th but is all down to who and where and whit?
You talk about this kind of music must also say whos and where.
PSS We Take upon ourselves the right not to brag about what kind of qualification we have. (Loads of svet and Blood in the trade since 1976 )
Don’t you Just love the way the WE form is used?
> Let me know how long those little suckers last with 2A bias and 24V rails
What happens if one would do that ?
The total dissipation is then 24x2 = 48W at steady state. Assuming you have the ideal heat sink at a sink temperature of 50°C. And you are using a good insulator like the Kerafol 86/82. The insulator will have about 5°C across it at 48W., so the MOSFET case temperature is 55°C.
The Toshiba MOSFET internal case to junction (silicon chip) Rth is about 0.83°C/W. So at 48W, this corresponds to 40°C. That means the junction temperature is 95°C, which is low enough if you believe in the Toshiba Reliability Handbook. Even if your heat sink is locally at 65°C, the junction temperature is still 105°C which is not yer outrageous.
http://www.diyaudio.com/forums/pass-labs/172770-balanced-f5-question-7.html#post2344426
But your total dissipation per channel is now close to 200W, instead of 128W for 16V rails. So you definitely need a larger heat sink than the Conrad, or you can use a slow running fan for forced cooling. The fan works wonders; easily brings you 10°C lower sink temperature, from my own experience.
Patrick
What happens if one would do that ?
The total dissipation is then 24x2 = 48W at steady state. Assuming you have the ideal heat sink at a sink temperature of 50°C. And you are using a good insulator like the Kerafol 86/82. The insulator will have about 5°C across it at 48W., so the MOSFET case temperature is 55°C.
The Toshiba MOSFET internal case to junction (silicon chip) Rth is about 0.83°C/W. So at 48W, this corresponds to 40°C. That means the junction temperature is 95°C, which is low enough if you believe in the Toshiba Reliability Handbook. Even if your heat sink is locally at 65°C, the junction temperature is still 105°C which is not yer outrageous.
http://www.diyaudio.com/forums/pass-labs/172770-balanced-f5-question-7.html#post2344426
But your total dissipation per channel is now close to 200W, instead of 128W for 16V rails. So you definitely need a larger heat sink than the Conrad, or you can use a slow running fan for forced cooling. The fan works wonders; easily brings you 10°C lower sink temperature, from my own experience.
Patrick
Last edited:
Favorite 9th
Bksabath,
Love your posts - you and I are on the same page. I am using a pair of Vandersteen Quatros right now - easy load, but not real efficient, (~84 dB per watt). My setup may be more sensitive to peak output voltage capability than yours is. And, no, I never questions Papa Pass 's judgements - he is almost always right. I guess I am just curious about how close I can get to a Pass XA160 with a couple wrinkles on the basic F5 circuit element.
As for the 9th, I love many versions, but Karajan with the Berlin Philharmonic is my favorite. (Bernstein with the NY is a close second).
I am getting more entranced with the English composers as I get older, (Williams, Britten, Buterworth, Elgar, and of course, Holst).
If they gave me one last piece to listen to as I prepare to meet my Creator, it would be Vaughan Williams "The Lark Ascending".
Bksabath,
Love your posts - you and I are on the same page. I am using a pair of Vandersteen Quatros right now - easy load, but not real efficient, (~84 dB per watt). My setup may be more sensitive to peak output voltage capability than yours is. And, no, I never questions Papa Pass 's judgements - he is almost always right. I guess I am just curious about how close I can get to a Pass XA160 with a couple wrinkles on the basic F5 circuit element.
As for the 9th, I love many versions, but Karajan with the Berlin Philharmonic is my favorite. (Bernstein with the NY is a close second).
I am getting more entranced with the English composers as I get older, (Williams, Britten, Buterworth, Elgar, and of course, Holst).
If they gave me one last piece to listen to as I prepare to meet my Creator, it would be Vaughan Williams "The Lark Ascending".
Tanks dcbingaman
My feeling is that to get close to what the XA 160 does you need to get close to what the XA 160 heat sink does (should say how efficient it is) and Papa runs TO3 at I believe about 25W (I need to look this up again)
As Patrick said with 24 V rails the mossfet will run at 48W this I feel is pushing a bit
So I feel that I will need to take the heath sinks and especially the thermal coupling to extremes that are not commercially viable options EG the Kerafol is certainly good and Beryllium oxide is even better (Beryllium oxide is not commercially viable as considered toxic) but then I am not going to sell those…
I was going to write a bit more about one Idea I have but better get ACAD out to make a picture for me.
Now Off topic
Karajan is fine (don’t get me wrong Maters of Taste are only for an Idiot to criticize)
Stolti and the Philly Philly do it for me as well.
About the Lark tank you so much Just got the Buzz (Goose Skin) just by reading it.
Forget ACAD going to listen to sometink right now…..
Al
My feeling is that to get close to what the XA 160 does you need to get close to what the XA 160 heat sink does (should say how efficient it is) and Papa runs TO3 at I believe about 25W (I need to look this up again)
As Patrick said with 24 V rails the mossfet will run at 48W this I feel is pushing a bit
So I feel that I will need to take the heath sinks and especially the thermal coupling to extremes that are not commercially viable options EG the Kerafol is certainly good and Beryllium oxide is even better (Beryllium oxide is not commercially viable as considered toxic) but then I am not going to sell those…
I was going to write a bit more about one Idea I have but better get ACAD out to make a picture for me.
Now Off topic
Karajan is fine (don’t get me wrong Maters of Taste are only for an Idiot to criticize)
Stolti and the Philly Philly do it for me as well.
About the Lark tank you so much Just got the Buzz (Goose Skin) just by reading it.
Forget ACAD going to listen to sometink right now…..
Al
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.