SYMEF amplifier

Hi Alvin P,

Thank you for your feedback. Your feedback is consistent with many members comments. Thank you again for your contributions to audio by building and reviewing this amplifier. Keep us posted. If you do find an amp that can really beat the SYMEF let us know. Its our pleasure to make your listening moments worthwhile.

kind regards,

Harrison.

Hi Harrison,

The sound is very transparent. It brings out the best of recordings specially of female vocals. I compared it to my AV receiver and I am impressed with the sound. It seems more natural and the music is more alive. With no input signal, there is no hum or hiss with my ears directly on the tweeters!

I used a 500w SMPS with additional 20kuF capacitors and I am very happy with it. The amp is completely silent.
 
Harrison, I had a friend build 2 channels of your Symef amp. Listening tests showed that voices were too forward and deep bass 'detached' from the rest of the music.

Your thoughts?

Hi Samuel,

Thank you for the second hand review. Your feedback is consistent with a few others below. The exciting part will be to extract the factors that differentiate the feedback :D

I currently have the amplifier Symef of Pinnocchio.

I agree with jkuetemann, about the sound of Symef.

The bass were a little too powerful, and the lack of high fluidity.

The great qualities of Symef are excellent definition in the register of medium-low. Also the soundstage is very good. As high a little more present and fluid, it would balance the tonal balance.

I do not think he lacks a lot to be perfectly musical.

denbret

hi harrisson,

These are speakers that I designed, Tubasson Mark 2, 3 channels with low hp (2) and medium SBAcoustic tweeter and Scan-speak Revelator 6620. I took two years to fine tune.

As I wrote above, the high frequencies are a little dry and would be more musical, if it was a little fluid.

I listen to different styles of music, Symef has a very detailed sound in the medium, at this level, it is a reference.

With a little less extreme low current and more fluidity in the high, the amplifier is in my favorites.

denbret

The SYMEF is a decent sounding amplifier, but for my tastes it is too forward in the midrange. The treble is smooth and the bass well controlled but for some reason it makes me feel the vocalist is in my lap.

I like the 1DIFFQC better to be honest and I have yet to build the 2DIFFET.

On the assumption that the SYMEF is a high definition amplifier :cool:, several things could account for these reviews
1. Perception in relation to expected or ordinary
2. Recordings
3. Speakers
on the account that SYMEF is not high definition amplifier :(
4. SYMEF

Your feedback is highly valuable. All the reviews are being factored in the research and your feedback is much appreciated. :)

In relation to 2 above, note that in the studio depending on how its done, we do our best to marry the bass, vocals and instruments. A non high definition amplifier will add a mask that seals the marriage :D

In relation to 3 above many speaker systems are designed to compensate for bass starved amplifiers

Disclaimer: A more thorough analysis is needed to get to the bottom of discrepancies

kind regards

Harrison.
 
In celebrating SYMEFs fifth birthday am taking the time to confirm her performance with songstresses. Many have claimed that she reanimates the songstress right into the room, others have claimed that she places the songstress right into your lap for a more personalised performance. There are many flavours one could try out from the reknowned Adele [https://www.youtube.com/watch?v=YQHsXMglC9A] to the more exotic Dela [https://www.youtube.com/watch?v=To-Wi2u9vvE]. SYMEF might well be the amplifier of choice for virtual reality environments.

When I started designing these amplifiers , I wanted to create a standard just like the ISO does. The SYMEF and 1DIFFQC et al were supposed to be suns* that other amplifiers could orbit around. Sure I havent designed amplifiers lately , other designs have come up and now its your job to tell us where they are parked in orbit.

*although many a designer may have mistaken an asteroid belt for the sun, passion might make it harder to separate fantasy from fact

Enjoy
 
Thanks Pinnocchio, glad you had fun. I guess the whole idea of the circlotron is to keep things simple. You see after many years of design Pass moved from amplifiers with many parts to just one transistor (plus a transformer or not). Sometimes many designs produced are concept blocks for bigger applications.

I haven't been thinking amplifiers much lately, toyed with the idea of a four-way speaker, as you know some diyers have speakers the equivalent of Ferrarris or Koniseggs when it comes to cars while others own speakers equivalent to hardy Toyota s. You see after you get your signal right, you need a speaker that will just play right

You know what they say about art, sometimes the artist has to step away from the art and take a siesta, on his return if he doesn't find himself with the urge to add or remove a brush stroke, then it is truly art

Not much has changed, Andrew T is still the top poster

Hi Joe
 
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After a seven plus year run these PCBs are due for an upgrade to improve serviceability, technology hasnt changed much so this amplifier might still be unbeatable, am not saying there isn’t a amplifier out there that could dance circles around SYMEF, its just that as a defacto standard and with existing technology, its just hard to beat. Banana plugs also have necessitated the need for a protection circuit to keep both speakers and amplifier safe, builders of this amplifier have showcased different protection circuits boards on their builds, kindly feel free to share these for review
 
A beautiful amplifier and amazing treat to your ears and soul

Here is my SYMEF in a case. It is such a beautiful sounding amplifier if you have this one your music comes to life. I'm not a good reviewer, but here are my observations.

This amplifier immerse you in music, and it puts an emphasis on the singer and brings him/her in front of you. One thing I have observe is this amplifier makes the speakers sound the way it wants to. I can tell this for sure, when I switch between different amps, this amp immediately brings its character to the sound. Other amps can't influence the sound that much, more or like dictated by the speakers, but this amp is special.

Thank you Mr. Harrison for the gift. It is kind of life time gift and stays with me forever.

One question Mr. Harrison, I would like to build version 2 PCB but want to operate at +/-50Vdc. Is it possible to run SYMEF at +/-50Vdc? If so what are the changes needed to the schematic? I will have adequate heatsinks for increased dissipation.

Thank you,
Routhun
 

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Thanks Routhan , good to know she still holds up and that your using at-least bare minimum protection for the most natural experience that being fuses.

She can easily do 50v but now designer starts getting worried about SOA, starts wanting to add beefier output to go with bigger sinks.

Truly humbled by your appreciation that met your need, thanks again for sampling

kind regards

Harrison.
Here is my SYMEF in a case. It is such a beautiful sounding amplifier if you have this one your music comes to life. I'm not a good reviewer, but here are my observations.

This amplifier immerse you in music, and it puts an emphasis on the singer and brings him/her in front of you. One thing I have observe is this amplifier makes the speakers sound the way it wants to. I can tell this for sure, when I switch between different amps, this amp immediately brings its character to the sound. Other amps can't influence the sound that much, more or like dictated by the speakers, but this amp is special.

Thank you Mr. Harrison for the gift. It is kind of life time gift and stays with me forever.

One question Mr. Harrison, I would like to build version 2 PCB but want to operate at +/-50Vdc. Is it possible to run SYMEF at +/-50Vdc? If so what are the changes needed to the schematic? I will have adequate heatsinks for increased dissipation.

Thank you,
Routhun