Help with my PSU

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I am trying to build an amplifier that I think is the most musical amplifier I have heard for normal money:)

The only problem was that it did lack a lot in the base and did not have a great control of the speaker.

I am assuming that it had something to do with a underpowered PSU.
I am also unsure if the amplifier will clip under large passages of classic deeeep church orgel?
It was a 60W amplifier

I am thinking of upgrading the transformer to a 600VA and the caps.

How would you change the PSU voltage, amp and caps?
 

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If you are working towards a Densen B100 Clone as per your previous thread, the power supply shown with a 300VA transformer is already more than sufficient for a 60W stereo amplifier. In any case, increasing the PSU's continuous current capacity will make little or no difference when the amplifier doesn't demand it. It was also stated that weak bass is a characteristic of "no global feedback" designs and this can only be compensated for by some form of equalization (bass boost).

I think this advice has already been given but it's an inherent flaw in the amplifier design approach that is the problem - though many users would say it isn't really a problem at all when overall sound quality is the higher priority.
 
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The schematic drawing is copied, I think, from the B100 schematic so no problem and the values and ratings of the power amplifier components will probably be correct but the substituted semiconductors are not what I would use - I would try to obtain and use transistors that were closer, if not the same type as the originals in any clone.

If the Densen product is what you like, then stay with your plan. The only proviso is that if you stray off the original design and layout, you may have stability problems that are too difficult to solve and you may then need practical assistance and expensive instruments etc. to solve problems. Try to locate the origin of that clone board and ask how it performed.

Living with the weak bass is probably the best option but having the further option of adding modest bass boost from a good quality preamp isn't such a terrible thing if the music requires it. The recording process probably already has had multiple boost/cut adjustments throughout every track of the final mix anyway. Be cautious though, when some guys tell you that having tone controls is bad audio karma or some such nonsense. Certainly, cheap tone control circuits are a bad idea but professional quality preamps are another matter.
 
I found this text from a Polish forum, where the schematic are displayed, it is the builder that writes:

Almost 2 years ago, I cloned this Dansen almost 100% by sticking to the original.
Without the power supply because I made it fast. It played a bit, then I threw it down ... I do not hide that SMD was aesthetically poor.
and I had suspicions about the semiconductor's originality

In general, is it worth to clone B100?
I asked myself this question and I will answer that I think so, because
- The originals are still scaring the price
- they are not new. I once had ... a tragedy. Everything on the plate after scorched, kondy and potek to exchange. Selector for putty ...
- they have a nice sound. Those who have them see what's going on.

So I decided to hit the theme for the second time and do it again.
The B100 version was probably 7 and in each of them the manufacturer was able to change semiconductors quite freely, keeping the same layout topologies.
I did the same :)
Final tranches I gave a popular 2SC5200 / 2SA1943, controlling 2SC4783 / 2SA1837 in the input differential system BC556, the rest is 2N5551 and 2N5401.
I gave up the short-circuit system.
Decreased gain (2k cities 500)

The whole thing sounded really good.
Better than the original;)

Well, it was worth it to make a housing.
I threw it into the DT1 from the toroids.
Only the tip because I have a preamp in a separate package.

The Densen B100 is a pretty immersive amplifier. You can once again on your favorite collection.
 
Ian Finch did advice me to change the substituted semiconductors, any advice on why, to what and so fort?
The original sound should be a bit to the high tonebalance, that could be great to lower a bit, I mean more warmth.


Final tranches I gave a popular 2SC5200 / 2SA1943, controlling 2SC4783 / 2SA1837 in the input differential system BC556, the rest is 2N5551 and 2N5401.
I gave up the short-circuit system.
Decreased gain (2k cities 500)

The whole thing sounded really good.
Better than the original;)

The Densen B100 is a pretty immersive amplifier. You can once again on your favorite collection.


Can anyone try to translate the Polish-GoogleEnglish?
 
Selecting the right PSU electrolytic capacitors?

I found this great comparison (High End Audio - Electrolytic capacitors) between different electrolytic capacitors that many refers to as a great guide. And I quickly found exactly what I was looking for! :)
Or so I thought BUT the Elna Silmic II are only in wary low values and the almost as good Black Gate (Rubycon) is so old capacitors that, if you bye them now you almost have to be changed them tomorrow due to age.
Then I did try to investigate some of the other, like the Panasonic ECA but that resulted in confusing info, about there be newer on with a lot better sound and so on and on and on:)

I am looking for musical, warm but detailed sound.
I have 56V rail to rail 14A.

What I am trying to do are to build a capacitor "staircase" where I use 2 x (large 22000uF, 47000uF, 10000uF, 5000uF, 1000uF and 1uF) to get capacity from the bigger and faster reaction time from the smallest.

Can anyone please try to help me to select the right ones?
 
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Design it and build it however you like, the hobby is called do it YOURSELF after all. I myself would select capacitors with a rating of 63 volts WVDC, because I like to have a margin of safety, and 63V > 56V. I would also select capacitors whose lifetime was guaranteed at 105 degrees C (not 85C), again because I like a margin of safety.

Something like this capacitor (link) might be my choice for the biggest capacitor in the progression.
 
When the output stage draws a lot of current (high volume into low-impedance load), the voltage across the 22000 uF capacitors will have a considerable ripple on it. Using separate rectifiers and electrolytic capacitors for the earlier stages reduces the amount of ripple that they see on their supplies.
 
The first two rectifiers (closest to the transformers) generate voltages from each transformer and stack the voltages. These voltages are used for the output stage (high current/power).
The third rectifier rectifies the voltages from the two transformers together to be used for the low power (and low current) part of the amplifier.
The idea is to avoid supply line noise from high currents in the (power) output stage to be propagated to the sensitive low power circuits.

If you take for instance a TDA7293 amplifier chip, it has got both high power and low power supply terminals with the same purpose of avoiding noise on the low power part from the high power output circuit.
 
The most important thing about a reservoir cap is not its brand, but its capacitance. Then comes ESR and ripple current rating. Then price/size.

To work out capacitance, first decide how much ripple you can tolerate and max supply current. Then calculate how much voltage the cap will drop during 10/8.33ms. If you want to be cautious you can double this value.

Bypassing is of little value, and might do harm if you are unlucky. Better to put decoupling where it is needed.
 
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