Please..read carefuly!
I only was agreeing in a tecnical way with the previous post...see
If i agree with this...you want that i keep my mouth shut!
Jorge
Resuming: you think that the KSA100 can't be improved!
I only was agreeing in a tecnical way with the previous post...see
If i agree with this...you want that i keep my mouth shut!
Jorge
Resuming: you think that the KSA100 can't be improved!
ROE = Roederstein
Those caps are Roederstein/Germany.
For ordinary (does not mean bad) industrial replacement caps take a look here:
http://www.buerklin.com
For more "audiophile" parts check:
http://www.schuro.de/
They have fine Elna Cerafine caps or Panasonic FC which should be very good as replacement.
I can`t see relays. On the picture there are capacitors again.
If there are relays as You`re at it replacing parts, IMO it is not a bad idea to consider replacing the speaker relays too.
I had quite some older amps (less than 10 years operating time!) where those relays gone bad. Even when there is nothing yet obviously wrong with them the time will come (probably soon)when You`ve to replace them (and according Murphy`s Law this will happen when You just closed the amps housing and finished the caps replacement job
).
Now we are three😉
Those caps are Roederstein/Germany.
For ordinary (does not mean bad) industrial replacement caps take a look here:
http://www.buerklin.com
For more "audiophile" parts check:
http://www.schuro.de/
They have fine Elna Cerafine caps or Panasonic FC which should be very good as replacement.
Servus Alex:
I can`t see relays. On the picture there are capacitors again.
If there are relays as You`re at it replacing parts, IMO it is not a bad idea to consider replacing the speaker relays too.
I had quite some older amps (less than 10 years operating time!) where those relays gone bad. Even when there is nothing yet obviously wrong with them the time will come (probably soon)when You`ve to replace them (and according Murphy`s Law this will happen when You just closed the amps housing and finished the caps replacement job
).
The Panasonic (Matsushita) FC series caps are an excellent choice for replacing old dried out electrolytics. Rated to very high temperatures, low ESR, smaller per-unit capacitance, long life, and excellent sound. I have even used them in the signal path to no ill effect. And a hellova lot cheaper than Black Gate.
Recommended.
Recommended.
I have to read carefully ?!!?
Please re-read your own comment. You provoke with such a remark and then you think I want you to shut up. Why would I want that ? 😀
Somebody asks for replacement parts and wants an answer, not a comment that changing components is .... ah well, you should understand by now.
Where did I say that ? First you tell me that I told you to shut up and now you tell me I think the Krell KSA100 can't be improved ?
Please re-read your own comment. You provoke with such a remark and then you think I want you to shut up. Why would I want that ? 😀
Somebody asks for replacement parts and wants an answer, not a comment that changing components is .... ah well, you should understand by now.
Where did I say that ? First you tell me that I told you to shut up and now you tell me I think the Krell KSA100 can't be improved ?
The sacred KSA 100!
At my age i know when a conversation goes anywhere!!!....
So i think that i am in a wrong forum where is suposed to talk of tecnical issues...
So lets continue talking about brands of capacitors...and resistors...and boxes...and cones...etc
PS By the way a have bougth a KST 100 in mint condition 1.000 Euros...and is know laiyng desassenbled in my workshop for a major lifting!
Cheers
Jorge
At my age i know when a conversation goes anywhere!!!....
So i think that i am in a wrong forum where is suposed to talk of tecnical issues...
So lets continue talking about brands of capacitors...and resistors...and boxes...and cones...etc
PS By the way a have bougth a KST 100 in mint condition 1.000 Euros...and is know laiyng desassenbled in my workshop for a major lifting!
Cheers
Jorge
Now there are 3...
Read this, as a post of a disapointed member...
I thougt that there are 2 groups,but....
Group 1---The typical audiophile that talk about brand marks...the most expensives and more in fashion the best (the month flavor)
Group 2-- The diyers that i belong...that think that topologies...interactions...interfaces...good design maters...As Baxandal, Black,Crowhurst...and others
But now i find that now we are 3
Group 3--A new one...similar to group one...that talk about brand marks...but of components!!!
Bye
Jorge
Read this, as a post of a disapointed member...
I thougt that there are 2 groups,but....
Group 1---The typical audiophile that talk about brand marks...the most expensives and more in fashion the best (the month flavor)
Group 2-- The diyers that i belong...that think that topologies...interactions...interfaces...good design maters...As Baxandal, Black,Crowhurst...and others
But now i find that now we are 3
Group 3--A new one...similar to group one...that talk about brand marks...but of components!!!
Bye
Jorge
Wow. I simply suggested the improvements in the event he didn't know. It might have spawned some interest.
Tube_dude
we all read Doug Self book. The world is full of CCSs, Cmirrors, high slew rate and low PSRR amp that sound like crap. A tube dude like yourself should know.
Why mess with something like the Krell anyway? If you don't like it just sell it and buy something else, or build something else.
we all read Doug Self book. The world is full of CCSs, Cmirrors, high slew rate and low PSRR amp that sound like crap. A tube dude like yourself should know.
Why mess with something like the Krell anyway? If you don't like it just sell it and buy something else, or build something else.
The danger of sugestions...
Hi RobPhill33...
Well we have learn a lesson...when someone ask for capacitors...we must not sugest anything else...
regards
Jorge
Hi RobPhill33...
Well we have learn a lesson...when someone ask for capacitors...we must not sugest anything else...
regards
Jorge
Ok...i give Up!!
I Buy it because for 1000 Euros i can't buy here the heathinks...many MJ 1524 /25...computer grade capacitors...a big toroid...and the other stuf...
My plans...put a Alps motorized ...put a remote...and make a classe A from scratch....
There is anything wrong in it???
Its diyer at its best...
Jorge
I Buy it because for 1000 Euros i can't buy here the heathinks...many MJ 1524 /25...computer grade capacitors...a big toroid...and the other stuf...
My plans...put a Alps motorized ...put a remote...and make a classe A from scratch....
There is anything wrong in it???
Its diyer at its best...
Jorge
When I order apples I don't want pears but when I have the apples in my bag a suggestion to buy pears too can work out.
Capacitor Problem
Hi Alex,
I agree with Jean-Paul that capacitors dry out with time. I experienced this in my Ampzilla too. 220µF went to 0µF!. The rubber seal becomes hard and brittle and tears. These Roedersteins are epoxy sealed, I think, but the old age and the high temperature in this class A Krell makes replacement a good move. You jumped to the small red ones but I would first replace the large blue main filter capacitors.
I have been using a speaker relay in my amplifier but eventually it was a cause if distorted sound! Look for burned contacts and carbon deposit on the plastic housing of the relay. Relays can give you much trouble.😎
Are the fans still working?😎
Hi Alex,
I agree with Jean-Paul that capacitors dry out with time. I experienced this in my Ampzilla too. 220µF went to 0µF!. The rubber seal becomes hard and brittle and tears. These Roedersteins are epoxy sealed, I think, but the old age and the high temperature in this class A Krell makes replacement a good move. You jumped to the small red ones but I would first replace the large blue main filter capacitors.
I have been using a speaker relay in my amplifier but eventually it was a cause if distorted sound! Look for burned contacts and carbon deposit on the plastic housing of the relay. Relays can give you much trouble.😎
Are the fans still working?😎
capacitor Krell KSA 100
Thank Elso
The fans are very good, not noises.
I have to change the blue capacitors.
Much better with a new capacitors.
Question:
I reading at RDE not ROE.
Perhaps I can not good read on the capacitor.
his you cocksure , that the capacitor a RDE is?
Many thank
best regards Alex
Thank Elso
The fans are very good, not noises.
I have to change the blue capacitors.
Much better with a new capacitors.
Question:
I reading at RDE not ROE.
Perhaps I can not good read on the capacitor.
his you cocksure , that the capacitor a RDE is?
Many thank
best regards Alex
Attachments
ROE is Roederstein, now part of Vishay. They were used frequently in Quad devices too.
Replacing them will pay off because they are sonically not that good too. They are sealed with epoxy but as Elso stated they are 15 years old and electrolytic cap-technology has changed by the years.
Replacing them will pay off because they are sonically not that good too. They are sealed with epoxy but as Elso stated they are 15 years old and electrolytic cap-technology has changed by the years.
Maybe a schematic will help making decisions. I would change the caps between Q1/Q2 and Q3/Q4 and in the feedback section for the best you can get.
While changing caps there are some other options if you want to know:
Change the input filter cap and all other small C's for Styroflex ( or Silver-Mica if they fit as Elso advises below ) if they aren't already. Change the 0.1 uF cap in the bias section for a pretty MKP if you like.
While changing caps there are some other options if you want to know:
Change the input filter cap and all other small C's for Styroflex ( or Silver-Mica if they fit as Elso advises below ) if they aren't already. Change the 0.1 uF cap in the bias section for a pretty MKP if you like.
Attachments
Updates and Upgrades
Hi Alex,
Ahaaa, the schematic!
I concur with Jean-Paul.
Also match to 1% on Beta all four inputtransistors Q1, Q2, Q3 & Q 4. Choose the highest Beta.
Bypass 470µf, 6V in he feedback loop with Polyprop.
Replace outputtransistors by MJL21193 and MJL21194.😎
Also match Q5 with Q6.
Replace all small ceramic caps by dipped silvermica (20 & 36pF)
http://db.audioasylum.com/cgi/m.pl?forum=tweaks&n=74451&highlight=curl+mica&r=&session=
If not already done make all small resistors 1%, 1/4 W metal film.😎
Hi Alex,
Ahaaa, the schematic!
I concur with Jean-Paul.
Also match to 1% on Beta all four inputtransistors Q1, Q2, Q3 & Q 4. Choose the highest Beta.
Bypass 470µf, 6V in he feedback loop with Polyprop.
Replace outputtransistors by MJL21193 and MJL21194.😎
Also match Q5 with Q6.
Replace all small ceramic caps by dipped silvermica (20 & 36pF)
http://db.audioasylum.com/cgi/m.pl?forum=tweaks&n=74451&highlight=curl+mica&r=&session=
If not already done make all small resistors 1%, 1/4 W metal film.😎
Hi Elso, that will be 16 new power transistors ! Isn't there a risk of instability when using other power transistors ?
Regarding bypassing electrolytics with MKP/Polypropylene:
I used to do this as good practice after listening tests in the past but the use of newer sophisticated electrolytics changed my opinion. Bypassing them sometimes gives negative results. Paralleling BG's always ends up with worse results than BG alone.
It was difficult for me to accept as I learnt in practice that bypassing them was better. Nevertheless I had to change opinion when I got to know the newer types. You know how difficult it is to change something that is hammered in your head. Well, it was for me anyhow. But facts are facts.
When leaving the original caps in place bypassing will be beneficial. But replacing them with high quality electrolytics is the same amount of work and the costs are minimal.
Regarding speaker protection relays:
Through the years I have seen too many defects with relays. Some investigation learned that some brands use gold plated contact-relays. Wrong because gold contacts are perfect for signal switching but not for current switching. They burn in because gold is too soft. When replaced with high quality sealed ( very important ! ) silver contact-relays the problems don't return. Sony amps ( Ta-af590/690 ) are famous for these defects as are some Nakamichi's.
As Cocolino pointed out, they fail mostly after you finished closing the case of the amp 😀
I am glad to see I am not the only one that edits his own posts several times !!!! 😉
Regarding bypassing electrolytics with MKP/Polypropylene:
I used to do this as good practice after listening tests in the past but the use of newer sophisticated electrolytics changed my opinion. Bypassing them sometimes gives negative results. Paralleling BG's always ends up with worse results than BG alone.
It was difficult for me to accept as I learnt in practice that bypassing them was better. Nevertheless I had to change opinion when I got to know the newer types. You know how difficult it is to change something that is hammered in your head. Well, it was for me anyhow. But facts are facts.
When leaving the original caps in place bypassing will be beneficial. But replacing them with high quality electrolytics is the same amount of work and the costs are minimal.
Regarding speaker protection relays:
Through the years I have seen too many defects with relays. Some investigation learned that some brands use gold plated contact-relays. Wrong because gold contacts are perfect for signal switching but not for current switching. They burn in because gold is too soft. When replaced with high quality sealed ( very important ! ) silver contact-relays the problems don't return. Sony amps ( Ta-af590/690 ) are famous for these defects as are some Nakamichi's.
As Cocolino pointed out, they fail mostly after you finished closing the case of the amp 😀
I am glad to see I am not the only one that edits his own posts several times !!!! 😉
Upgrades and Updates
Hi Jean-Paul
To avoid instability I recommended these not ultra high bandwith types and NOT 2SC3281 and sister/brother. These transistors were recommended by no one less than the famous audio designer James Bongiorno. He also uses these types in his already famous Ampzilla 2000.
www.ampzilla2000.com
James states these transistors are more linear than MJ15024 and MJ15025.
Again you are right, Jean-Paul the MJL21193 and MJL21194 have a slightly higher gain bandwith product than the MJ15003 and MJ15004 (4 to 2 MHz Min.) So be carefull.
I have absolutely no experience with Blackgates. 470µF bipolar is a rather large cap. Only place in my amp for 3.3µF polypropylene and 470µF bipolar from Intertechnik.
Again I concur if a bipolar Blackgate fits in use it if you have the funds and the patience to wait for the "burnin" process to complete......🙄
jean-paul said:
Hi Jean-Paul
To avoid instability I recommended these not ultra high bandwith types and NOT 2SC3281 and sister/brother. These transistors were recommended by no one less than the famous audio designer James Bongiorno. He also uses these types in his already famous Ampzilla 2000.
www.ampzilla2000.com
James states these transistors are more linear than MJ15024 and MJ15025.
Again you are right, Jean-Paul the MJL21193 and MJL21194 have a slightly higher gain bandwith product than the MJ15003 and MJ15004 (4 to 2 MHz Min.) So be carefull.
I have absolutely no experience with Blackgates. 470µF bipolar is a rather large cap. Only place in my amp for 3.3µF polypropylene and 470µF bipolar from Intertechnik.
Again I concur if a bipolar Blackgate fits in use it if you have the funds and the patience to wait for the "burnin" process to complete......🙄
2SC3281 and sister/brother are not available anymore ( the original Toshiba's that is ).
You are right about the 470 uF 6V being bipolar, didn't see that at first. But I would replace it anyway with a new one. And I would buy a 10 or 16 V version if it fits on the board.
The "burn in" time of BG is over-emphasised by those that just don't like them without ever having tried them. Please try them once, BG NX HiQ for decoupling supply lines in DAC's are the best I ever heard on that place.
I can assure you that the small amount of time weighs up to the tremendous soundquality you get in return. Just got my bipolar 4.7 uF N series and will try them for use in the signal path the next days. Something I certainly wouldn't have done in the past !
You are right about the 470 uF 6V being bipolar, didn't see that at first. But I would replace it anyway with a new one. And I would buy a 10 or 16 V version if it fits on the board.
The "burn in" time of BG is over-emphasised by those that just don't like them without ever having tried them. Please try them once, BG NX HiQ for decoupling supply lines in DAC's are the best I ever heard on that place.
I can assure you that the small amount of time weighs up to the tremendous soundquality you get in return. Just got my bipolar 4.7 uF N series and will try them for use in the signal path the next days. Something I certainly wouldn't have done in the past !
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