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Pliers and screwdrivers, and an hour or two of your spare time. That is all you need.
What you get: The Poweramp 5, one of the best sounding power amplifiers* you can get, no matter what you pay.
You will hear no distortion of any kind. Only the music, pure and clean, thanks to very careful design using only discrete components. It took us two years (!) and over 30 prototypes to get the amplifier perfected.
*) Sensitivity 910 mV for 2 x 50 W power output. This means most CD- and DVD players, DACīs, Bluetooth adapters and desktop computers can be connected directly without any preamplifier if you wish to do so.
(When you see stars (*, ** et.c.) in the text below, you find the explanation at the bottom of this page.)
There are a lot of "good enough"* amplifiers on the market, but we wanted to make something much better. An amplifer that would satisfy even the most choosy music lovers, audiophiles and recording studios.
So we set up this goal:
An amplifier that does not change the sound at all, just amplifies the input signal in as perfect detail as possible. Because that is how a real Hi-Fi power amplifier should work:
No reshaping of the signal, just amplification.
We and our customers should be able to fully enjoy our music for hours without getting irritated over anything, and not getting any listening fatigue**.
The Poweramp 5 uses the fifth (and probably the last) generation of our amplifier modules.***
Everything, down to the smallest detail is reproduced with high precision. Every breath a singer takes, every sound when a guitar player touches the strings, faint room acoustics... If it is in the recording media you will hear it. Neither too strong or too weak, but just as it is meant to be.
This means that the amplifier is suitable for all kinds of music. Soft jazz will sound soft, rough rock music will sound rough. Just as it is recorded.
Have a look at the assembly instructions here. There you can also see what parts are included in the kits.
Notice that there is no soldering. You only use simple pliers to secure the sockets and potentiometers. And two screwdrivers, one for slotted screws (most of the electrical connections) and one for crosshead screws (PZ1, for securing the wood parts and some other components).
We have sold these amplifier kits in Sweden for some years now. Carpenters, floor dressers, engineers, café owners and garbage men are among our customers, most of them with no previous experience from building electronics. And they have all succeded in assembling the amplifier in just an hour or two.
Depending on your mains voltage, you have two kits to choose from.
Both kits contain two amplifier modules with heatsinks, power switch, AC socket with fuse holder, gold plated loudspeaker sockets (for wires, fork contacts or banana plugs), RCA sockets, volume controls with knobs, ready-built PSU board with self-resetting fuses, all wires et.c. and all the wood parts and screws for the box (as in the picture above). The kits donīt include the power cable, as wall sockets vary from country to country. But it is the cable normally used for desktop computers, so you can get it at most department stores and computer dealers. See picture below.
VERY IMPORTANT: Limited production rate, only three kits per week!
Valutronic is a family business, run by only two persons. We do all soldering by hand for maximum reliability.
Building and testing the amplifier modules and PSU board, cutting cables, keeping everything in stock, putting the kit together, do all paperwork et.c. takes about one full workday for each kit.
As we also have to take care of the shop, ship packages to customers and do all computer work (like this website) the production capacity is very limited.
Therefore, do not try to send us any payment without first consulting us via e-mail. We will reply and tell you when your kit will be ready for shipment, and send you a PayPal Money Request. If the payment has arrived in time, the shipping will be carried out on the agreed date.
PA5L. Everything except the power cable, including the transformer. This kit is only for countries where the mains voltage is 220 or 230 VAC. If your mains voltage is higher or lower, choose the PA5X kit instead.
All you need to buy separately (if you donīt have them already) are the tools (pliers and two screwdrivers) and the power cable.
All prices are the total sum you pay to us, including shipment.
(Prices in parenthesis are calculated using the exchange rates from 7 november 2019)
EU countries, VAT included: 4835 SEK (approx. 454 Euro / 392 GBP / 3405 DKK)
Norway, Iceland, Faroe Islands, Greenland, Åland: 3989 SEK
Europe 1, see list below: 3993 SEK
Europe 2, see list below: 4012 SEK
USA, Canada: 4253 SEK (approx. 442 USD / 582 CAD)
Rest of the world where PayPal works, like Australia, New Zealand, countries in Central and South America and most African and Asian countries: 4294 SEK (approx. 646 AUD / 702 NZD)
PA5X. The same kit but without the mains transformer and its mounting kit (rubber washers, metal washer, bolt and nuts).
This kit is for countries where the mains voltage is not 220 - 230 V (or if you already have a suitable transformer or prefer to buy the transformer locally).
All prices are the total cost you pay to us, including shipment.
(Prices in parenthesis are calculated using the exchange rates from 7 november 2019)
EU countries, VAT included: 4476 SEK (approx. 420 Euro / 362 GBP / 3152 DKK)
Norway, Iceland, Faroe Islands, Greenland, Åland: 3686 SEK
Europe 1, see list below: 3690 SEK
Europe 2, see list below: 3707 SEK
USA, Canada: 3844 SEK (approx. 399 USD / 526 CAD)
Rest of the world where PayPal works, like Australia, New Zealand, countries in Central and South America and most African and Asian countries: 3881 SEK (approx. 584 AUD / 634 NZD)
Mains transformer: Preferably a toroidal transformer like the one you see in our assembly instructions. Other types may produce a stronger stray magnetic field that can cause a low humming sound.
Power capacity: 160 - 220 VA. The closer to 160 VA the better, as more power capacity only makes it bigger and heavier, and more idle power makes it warmer.
Primary voltage must be the voltage you have in your wall sockets.
Secondary voltage should be between 2 x 22 and 2 x 24 V AC for full output power (2 x 50 W). If you live in a country where voltage is unstable, choose a few volts lower secondary voltage. 2 x 18 V will result in an output power of about 30 W per channel, which is a little more than 2 dB lower than normal, hardly noticable but much safer if you mains voltage is unstable.
In the PA5C kit a 160 VA transformer is used. Diameter 105 mm, height 45 mm. However, there is room in the amplifier box for a tranformer with a diameter of up to 125 mm and height 65 mm.
Donīt forget the mounting kit when ordering a transformer, if this is not automatically included. (Two rubber and one metal washer.) And the bolt + nut for screwing the tranformer in the box. See the assembly instructions.
*) The "good enough syndrome". It is very common these days. Mass produced products that are just about "good enough" for people with low demands. Clothes that wear down of loose colour quickly, but "good enough" because they go out of fashion anyhow. Laptops that only last for a few years. Sound equipment is no exception:
Most people are used to the mediocre sound from earphones connected to smartphones. They have low expectations and settle for "good enough".
That is why most modern amplifiers use cheap integrated circuits instead of separate discrete components. It is cheaper, it is quicker, and still "good enough" for the multitude of people who have low expectations.
But that does not mean that they can not hear the difference, because most people can if they get the chance to compare. We see this all the time. Persons who enter our shop, listen for a while, and then say something like "I did not know music could sound this good". Or they tell us that the music, when played through our Poweramp 5 plus our SQ-50H speakers has so much more detail than they are used to.
**) A typical "ordinary amplifier" problem you might recognise: After listening to music for half an hour or even less, you then feel like turning down the volume or shut it off completely. Even if it is music you love you still get tired rather quickly. It is called listening fatigue, and av very common reason is TIM (Transient Intermodulation Distortion). To avoid it the amplifier must react quickly to input signal transients. For that reason, we use very fast components, all the way from input to power output to eliminate this problem.
You will find that with the Poweramp 5 you can listen for hours without having to "rest your ears".
***) The evolution of our CM-50 amplifier modules is a long story.
The first amplifier module, from 2009, was a rather straight-forward, simple design: A balanced input stage, two 1-transistor current sources for the input- and drive stages with a common LED as voltage source, a resistor + 1-transistor driver stage, temperature sensing transistor, quiscient current adjusted with a potentiometer, and finally the power transistors. Early in the design phase we abandoned bipolar power transistors and went for the more expensive, but much quicker HEXFET power transistors we have used since then. It made the cuiscient current circuit a bit more complicated, but the sound was so much better. This amplifier was very sensitive to short circuiting (just milliseconds of short circuiting the loudspeaker terminals could ruin the amplifier) but we warned about it and there were no problems.
At startup there was a "bump" in the loudspeakers, not very loud, but anyhow. And if one forgot to put fuses in all places, loosing plus or minus from the PSU would destroy the power module within a second. So you had to be careful when building and connecting these early amplifier modules, but only one of all our customers ran into this problem. The simple design also resulted in a rather low damping factor. When driving loudspeakers with high return currents like the bass driver in our SQ-50 models the amplifier did not have a "steady grip" on the bass driver cone, making the deepest bass tones a little weak. Noone complained, however, maybe because this is a common weakness in many amplifiers, and ours had a better overall sound quality than most. And as most music does not contain frequencies below 40 Hz at high enough volume, noone had any complaints. Quite the opposite, our customers were extremely happy, some of them even sold their very expensive / exclusive amplifiers and bought our amplifier instead.
Then, step by step we perfected the amplifier modules.
A special circuit that took care of the missing supply voltage problem was introduced, now it could loose plus or minus from the Power supply board without any harm to the amplfier or the loudspeakers. And a current limiting circuit was also included to protect against temporary short circuiting the output. (This became CM-50 MK II)
After doing some tests with loudspeakers that had a high BxL factor and produced rather high reverse currents that de-stabilized the amplifier (only heard when playing a part of a trumpet concerto!) we separated the current sources, changing from a common voltage source driving two 1-transistor current sources to two separate 2-transistor current sources. This solved this (unusual, but nevertheless existing) problem. (This became CM-50 MK III)
The next development was a huge step forward. A total change of quiscient current stabilization technique.
Many years earlier we had worked on a current (not voltage) amplifier for Volvo cars in Gothenburg. A few years after that we were contacted by a company that needed an amplifier that had to be placed in a closed box outdoors. The ambient temperature could vary from -40 to +60 ºC. Normal thermal feedback was inadequate, so we had to re-think completely. Then we remembered the "Volvo" amplifier and got a brilliant idea based on a part of that design. A circuit that not only stabilized the cuiscient current, but also was almost independent of supply voltage changes, and needed neither thermal feedback nor manual adjustment. That amplifer worked perfectly, so we decided to use the same design in our power amplifier modules. The stable cuiscient current is essential for keeping the sound quality constant over a long period of time, and protecting the amplifier from overheating due to cuiscient current drift, the most common reason why old amplifiers suddenly break down. So, now we had an amplifier that would maintain the same top quality sound after many years as it did when it was brand new. And as there is no need for setting the quiscient current, the installation was simplified, too. (This became CM-50 MK IV)
Still we had not found a way to totally remove the limited deep bass response when using loudspeakers with high current feedback. So we searched for a way to increase both the damping factor and reverse current resistance, without affecting the sound quality, which is always our number 1 priority. We did some research and tests, and finally found the solution: A current mirror circuit instead of the two load resistors at the input transistor collectors. This both linearized the signal even further and increased the damping factor and made the amplifier counteract reverse current from the loudspeakers without loosing stability. CM-5018, the amplifier modules used in the Poweramp 5 was born.
The first time we listened to the new amplifier we were extremely satisfied. The overall sound quality was perfect, no audible distortion of any kind and excellent reproduction of even small details. And now with a verysolid, deep bass as well, no matter what loudspeakers and filter combinations we used. Since then (early 2018) a number of people have brought their own amplifiers to the shop for a comparison, but not one of them could manage complex music and deep bass as well as the Poweramp 5.
Even some "audiophile brands" have had no chance when doing a direct comparison.
This is why we feel totally confident that the CM-5018 power modules used in the Poweramp 5 will be the last generation of its kind, there is nothing left to improve. The sound quality is unbeatable, noise is extremely low, installing is simple, and aging is no problem at all.