• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

advice on changing bridge rectifier

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DF96 I am new to the building & tweaking of tube gear .I purchased the amp off ebay from j sound lab over 12 months ago and have caught the bug and have been slowly upgrading caps resistors opt as my level of understanding tube amps grows the more i want to learn.
Having had very good results in the changes made to the amp and pleased with the results the bug has bitten. I have a long way to go understanding circuits and terms used in electronics but am willing to learn hence the user name WTL.I am sorry but i still have training wheels and at a basic level.I Am finding it hard to sift through the hype and mumbo jumbo on the net about tube gear. Thank you for the reply. Steve.
 
I have a SE tube amp with generic bridge rectifiers in ps kbl407 4a 1000v Is it worth the effort to change these for soft recovery type .And if so what type.
Any Ideas. Steve.

DF96 is right, the use of soft recovery diodes is less important if important at all vs ensuring caps are in good condition and low levels of inductive coupling,

Having a schematic of the SE tube amp, a good multimeter and scope are recommended.
also be aware of high voltages,:eek: within tube amps, requiring that you power down, including removal of power cord from power socket, before undoing any casework. and be aware that caps can remain for hours charged. A good practice is place bleed resistors to reduce charge, which SE may and probably have already attended to. if any of this sounds unfamiliar then please allow SE themselves or a electronics technician to perform this work..... DiY is encouraged of course, but also advised with suitable cautions, particularly with tube gear.

You can be fairly sure SE have designed your amp well.:)

Cheers / chris
 
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Thank you for the advice Chris,I take care when working on the amp, bleed resistors are installed .I have replaced all the wiring with solid silver teflon jacket,Magnequest DS025 opt"s,V Cap teflon coupling caps,ASC 386S in ps and caddock& shinkoh resistors signal.
Tubes EML 300B,EML 5U4G Mesh Rectifier, Russian 1578 driver .The amp sounds pretty good in my humble opinion but there's always room for improvement, as i said i have got the bug... My Krell KSA 50 sits collecting dust. Regards, Steve.
 
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Thank you for the advice Chris,I take care when working on the amp, bleed resistors are installed .I have replaced all the wiring with solid silver teflon jacket,Magnequest DS025 opt"s,V Cap teflon coupling caps,ASC 386S in ps and caddock& shinkoh resistors signal.
Tubes EML 300B,EML 5U4G Mesh Rectifier, Russian 1578 driver .The amp sounds pretty good in my humble opinion but there's always room for improvement, as i said i have got the bug... My Krell KSA 50 sits collecting dust. Regards, Steve.

If you have changed components to this degree,

The type of diode may make a difference. If snubbers are used then less so.
UF soft recovery have a different "sound" call it what you will. Hexfred are probably the best all round, only my opinion. The UF can sound bright, soft recovery warmer. Hex in the middle of the two. Schottky are supposed to be better (Im not a fan). The voltage must be high enough and current for any inrush. You will get to a point where the music starts to sound strange and disjointed if you just keep upgrading. Then you will find that you can't get it to "sound right". Then you can't live with it by going back..this is the problem with a constant upgrade path. Any weak sources will show.
Then again its DIY so have fun and be carefull. No further comment. :)

Regards
M. Gregg
 
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Last comment..LOL

A list of "Annoying" components..LOL

OK

Hexdiode Example

HFA15TB..at low current no heat sink is required however they need to be isolated from chassis.

http://www.irf.com/product-info/datasheets/data/hfa15tb60.pdf

BYV96E.

http://www.datasheetcatalog.org/datasheet/philips/BYV96_1.pdf


Compared to a 1n4007 the 96E is closer to a valve rectifier without the sag.
I don't have an example of schottky I guess someone will add an example. :)
I promise not to add any more..Again correct ratings are important.


Regards
M. Gregg
 
Sorry if i have offended you DF96,I purchased this amp to learn about the workings of a tube amp,and over time have changed many different components of varying quality and price.I had thought about buying a kit amp but did not have the knowledge or confidence to do so .Slowly i am beginning to understand about circuits,and to read schematics,I did not mean to sound like some ****** with to much money,I just asked a simple question about something i was not sure about .Again sorry if i have offended anyone.
Regards, Steve.
 
No apology needed. I was not offended, merely amused. Lots of people seem to be drawn down this boutique route, as they are encouraged by others who have gone before. I just find it amusing when I see (mainly on other sites rather then here) people debating the merits of this brand versus that brand of resistor/capacitor when it is clear that they don't actually understand how the circuit works and how to choose the most important thing: the component value.

Component quality does matter. Capacitors should have the appropriate dielectric. Circuit design is far more important, and you can't assume that commercial equipment has got that right.

Audiophiles buying components can be a bit like women buying perfume: paying £100 for £2 of industrial chemicals in a fancy bottle with a nice story attached. If exactly the same product was available in a plain bottle with no story for £10 few would buy it, even if they knew this was the case. They are not buying some chemicals, they are buying a story, a dream, a lifestyle choice.
 
No truer words could be spoken. Well said, DF96.

Such strange pathological science, like numerology for circuit components and wires. If we don't know how it works, it is magic.



No apology needed. I was not offended, merely amused. Lots of people seem to be drawn down this boutique route, as they are encouraged by others who have gone before. I just find it amusing when I see (mainly on other sites rather then here) people debating the merits of this brand versus that brand of resistor/capacitor when it is clear that they don't actually understand how the circuit works and how to choose the most important thing: the component value.

Component quality does matter. Capacitors should have the appropriate dielectric. Circuit design is far more important, and you can't assume that commercial equipment has got that right.

Audiophiles buying components can be a bit like women buying perfume: paying £100 for £2 of industrial chemicals in a fancy bottle with a nice story attached. If exactly the same product was available in a plain bottle with no story for £10 few would buy it, even if they knew this was the case. They are not buying some chemicals, they are buying a story, a dream, a lifestyle choice.
 
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