tttking
Why are the layers mirrored? Is this right? I dont know but this is suspicious. You may have ask your PCB-maker.
Why are the layers mirrored? Is this right? I dont know but this is suspicious. You may have ask your PCB-maker.
Dear Pavel and Greg:
Thank you for your input. I found out the 274X CAM file came with the Eagle software does not generate .sol file properly. I have obtain other CAM files from the internet which worked.
Terry and Sheldon:
I would like to spend some more time double check the files before I am ready for the PCB maker.
Thank you for your input. I found out the 274X CAM file came with the Eagle software does not generate .sol file properly. I have obtain other CAM files from the internet which worked.
Terry and Sheldon:
I would like to spend some more time double check the files before I am ready for the PCB maker.
Hi Guys,
I got the new 5_3 boards working. I forgot to change the 22R's for 47R's. What was it that that was supposed to do for the sound? I still don't have a poly cap for the input so I used a Bi-polar electro 10uf in there. It's too much hassle to change between the 5_3 and the 5_2 boards right now to see how much difference there is. maybe once I get them in cases. I was able to compare it to my Leach Low TIM. They are similar with the Sym having a tad more highs. This is the best match I've ever had for my JBL 4425 monitors. You don't notice the lack of extended highs with this amp.
Here are some pics.
I got the new 5_3 boards working. I forgot to change the 22R's for 47R's. What was it that that was supposed to do for the sound? I still don't have a poly cap for the input so I used a Bi-polar electro 10uf in there. It's too much hassle to change between the 5_3 and the 5_2 boards right now to see how much difference there is. maybe once I get them in cases. I was able to compare it to my Leach Low TIM. They are similar with the Sym having a tad more highs. This is the best match I've ever had for my JBL 4425 monitors. You don't notice the lack of extended highs with this amp.
Here are some pics.
still4given said:
Hi Terry !
Nice to hear that you got them running. What was causing the problem ?
These 47r instead of 22r slightly increase dynamics and bass punch.
Have you already heard the symasyms on other speakers ? What do you think about the musicality of symasym ? How does it compare to your Krell clone ?
Maybe someone start a thread "Symasym5 Amp - Listening impressions" ? 😀
Mike
This is a hell of an idea, Mike..., even though you don't have a
commercial version of this "explendid" amplifier.
If you had such a commercial version I would have to start
saying that the Symasym doesn't need esoteric components or
any kind of gimmicks, is a pure design that works well with all
kinds of components, with the same quality. I can atest
for that, I've used a lot of crappy components with all the three
versions I've built, always with almost the same results.
Only the latest one I went over board and I bought the
most sofisticated components my purse could afford.
So, if this is a start for the listening impressions, I didn't write
one, I only want to write about the sofistication of the design
that works rather well with even parts that I have used and
used again before.
commercial version of this "explendid" amplifier.
If you had such a commercial version I would have to start
saying that the Symasym doesn't need esoteric components or
any kind of gimmicks, is a pure design that works well with all
kinds of components, with the same quality. I can atest
for that, I've used a lot of crappy components with all the three
versions I've built, always with almost the same results.
Only the latest one I went over board and I bought the
most sofisticated components my purse could afford.
So, if this is a start for the listening impressions, I didn't write
one, I only want to write about the sofistication of the design
that works rather well with even parts that I have used and
used again before.
MikeB said:
Hi Mike,
Since you probably know the math, what size resistor will work in parallel with the 22R to give me 47R I may have those on hand?
I have three sets of speakers in my studio. JBL 4425, JBL 4411 and Event 20/20 nearfields. The Symasym sounds nice through all of them but makes the most difference with the 4425. The amp is very bright sounding. Even more-so than the Leach Low TIM. Of course if you look in the pics you can see that I have everything hooked up with very small wires, even the speakers. I am sure some improvement will be achieved with proper cables. I don't remember the 5_2 boards sounding quite this bright. Maybe they were and I just don't remember. I plan to mount both sets in proper cases and with proper PSU's and then I will be able to better compare them.
I did switch between the Krell, the Low TIM and the 5_3. It is difficult to compare using one preamp because the Symasym has so much more gain. By the time you adjust the volume you have lost the memory of the previous amp. Once I get the Symasym mounted in a good box I will use separate pre's and do a better comparison test.
I must say, my wife was very impressed with the sound. Usually she will say she can't hear a difference but she really liked the way this sounded.
Maybe someone start a thread "Symasym5 Amp - Listening impressions" ? 😀
Yeah, I wonder how many folks we could get to review it without ever having heard it. 😀
Blessings, Terry
Edit: I forgot to answer about the problem. I never could get the other two boards working so I etched two new ones. I needed to use some of the parts from the bad boards and when removing the output emitter resistors I discovered that I have a bad solder joint on one of them, just as you had suggested. I did try to reflow the solder but Iguess it was still bad. I never could figure out the other one. It had almost rail voltage on the outputs. The good thing is that both of the new boards worked first try.
Hi Terry, by putting resistors in paralell they always get smaller, so no chance by adding resistors. The formula: Rnew = 1/(1/R1 + 1/R2)
Symasym should not sound bright, only very clear and transparent... Okay might be choice of words. 😀 And yes, 5.3 sounds clearer than 5.2. It does sound "bright" in a soft way...
Mike
Symasym should not sound bright, only very clear and transparent... Okay might be choice of words. 😀 And yes, 5.3 sounds clearer than 5.2. It does sound "bright" in a soft way...
Mike
Thanks for the equation. I will keep that for future reference. I will stop at the store and get the proper size and swap them out.
I didn't mean bright as a negative term. It's just that the highs are very strong in this amp. Cymbals sound natural though.
I tried a few different types of recordings and my jazz albums are very nice through this amp. I have some choral stuff that sounds a bit edgy though. Probably the way it was recorded, but the Symasym doesn't help disguise it very well. I think the Krell wins in that category. It will take a bit of listening to get the hang of this amp. The dynamics are very good but it shows off bad recording for what they are. I'll bet this amp will be great for mixing since it is so true. I'm just not sure yet if it will be my everyday listening amp. Time will tell. It has a lot of "Wow" factor. When you first fire it up it is quite impressive.
I like that the parts are easy to get. Well, except for that 10uf input cap for some reason. I still would like to try it with a couple of TO-3's for outputs. I may do that before I'm done.
Blessings, Terry
I didn't mean bright as a negative term. It's just that the highs are very strong in this amp. Cymbals sound natural though.
I tried a few different types of recordings and my jazz albums are very nice through this amp. I have some choral stuff that sounds a bit edgy though. Probably the way it was recorded, but the Symasym doesn't help disguise it very well. I think the Krell wins in that category. It will take a bit of listening to get the hang of this amp. The dynamics are very good but it shows off bad recording for what they are. I'll bet this amp will be great for mixing since it is so true. I'm just not sure yet if it will be my everyday listening amp. Time will tell. It has a lot of "Wow" factor. When you first fire it up it is quite impressive.
I like that the parts are easy to get. Well, except for that 10uf input cap for some reason. I still would like to try it with a couple of TO-3's for outputs. I may do that before I'm done.
Blessings, Terry
Hi Terry, you might try the Toshibas as outputs (sc5200/sa1943), they make the sound a bit softer, more "natural", the MJLs sound a bit grainy compared to them. Or if you have some left, MJL21195/4...
Symasym starts to play one league above when fed with SACD...
Of course i don't know the sonic influence of the elyt inputcap.
Mike
Symasym starts to play one league above when fed with SACD...
Of course i don't know the sonic influence of the elyt inputcap.
Mike
Hi Mike,
I do have some MJL21195/6's. I could try swapping them in and see what difference it makes. As far as the input cap goes, I tried jumping it and heard no real difference. I will get the proper caps when I can find them. Maybe I'll try swapping out the outouts on one channel only and then listen to the difference. I should also move the stuff to another room and listen. The acoustics are not the best in my studio and the Symasym may be revealing that. Like I said, It is the best match I've found for the 4425's. They only go to 16khz and tend to have a bit of a loose low end. This amp makes them sound lovely. You should hear a tenor sax through this combination. Amazing! I would Love to hear a SACD through it.
Blessings, Terry
I do have some MJL21195/6's. I could try swapping them in and see what difference it makes. As far as the input cap goes, I tried jumping it and heard no real difference. I will get the proper caps when I can find them. Maybe I'll try swapping out the outouts on one channel only and then listen to the difference. I should also move the stuff to another room and listen. The acoustics are not the best in my studio and the Symasym may be revealing that. Like I said, It is the best match I've found for the 4425's. They only go to 16khz and tend to have a bit of a loose low end. This amp makes them sound lovely. You should hear a tenor sax through this combination. Amazing! I would Love to hear a SACD through it.
Blessings, Terry
Yes, you could try the MJL21195/6. Be careful, the MJL21196 is the NPN ! (No idea why Motorola reversed the numbering for these)
Shorting the inputcap is risky, you might get large dc-offset. (30mv... 😀)
Yes, instruments like sax sound impressive on symasym. Try guitars ! (acoustic)
Mike
Shorting the inputcap is risky, you might get large dc-offset. (30mv... 😀)
Yes, instruments like sax sound impressive on symasym. Try guitars ! (acoustic)
Mike
Hi Mike,
Yes, I did listen to some acoustic guitar as well. Fiddle is really something as well. Seems anything that benefits from crystal clear highs will sound great on this amp. A Steinway is especially nice.
I'm going to let this all burn in for a while before I swap the outputs. I want to see what it will do like this first. I checked the DC offset after jumping the cap before I hooked up the speakers. This amp only has about 6mV offset.
Blessings, Terry
Yes, I did listen to some acoustic guitar as well. Fiddle is really something as well. Seems anything that benefits from crystal clear highs will sound great on this amp. A Steinway is especially nice.
I'm going to let this all burn in for a while before I swap the outputs. I want to see what it will do like this first. I checked the DC offset after jumping the cap before I hooked up the speakers. This amp only has about 6mV offset.
Blessings, Terry
Guys, I have one basic question : by which format are you testing and comparing these amps ? CD, DVD-A or SACD ?
Hi Upupa, i test most time with CD, but the difference between SACD and CD is frightening. While CD tends to sound bright/harsh (minor), with SACD the sound is simply "perfect"... Somehow just like it should be ! I have only one DVD-A...
Mike
Mike
Upupa Epops said:
Why, MP3 of course. 😀
Just kidding. Mostly CD for me. I don't own SACD yet or DVD-A.
Blessings, Terry
MP3, at first I tought your'e serious...But that's ok, as long you don't judge an amplifier(especially this Symasym) with MP3 recordings. Ah, Ah, good joke!
Another thing is your JBL 4425, they are a little harsh on the
treble, no wonder you had that experience.
I never understood why people are so devoted to JBL, I never
found them very sofisticated, they exibit a treble very improper
to consumption. I still remember the recording studio I worked
for that had to switch to Tannoys gold just because of that.
At the time the JBL's were the monitor/reference speakers and
everything was high, high, higher, too high and irritating to evaluate what was coming out of the lathe making an LP. Even
the mid range was awful and that had to be taking in account
when making a record (At the time was a record, an LP).
Personally, I thank God not to have to deal with them at the
home level.
On another note I used MJL21193/94 in my latest Sym. What's
the difference between these and the 95/96?
Another thing is your JBL 4425, they are a little harsh on the
treble, no wonder you had that experience.
I never understood why people are so devoted to JBL, I never
found them very sofisticated, they exibit a treble very improper
to consumption. I still remember the recording studio I worked
for that had to switch to Tannoys gold just because of that.
At the time the JBL's were the monitor/reference speakers and
everything was high, high, higher, too high and irritating to evaluate what was coming out of the lathe making an LP. Even
the mid range was awful and that had to be taking in account
when making a record (At the time was a record, an LP).
Personally, I thank God not to have to deal with them at the
home level.
On another note I used MJL21193/94 in my latest Sym. What's
the difference between these and the 95/96?
still$given-
Maybe someone start a thread "Symasym5 Amp - Listening impressions" ?
Yeah, I wonder how many folks we could get to review it without ever having heard it
------------------------------------------------------
subjective comparisons to ska,aksa,symasym abc lets see how they sound
or is it just pseudo hype they talk about, a good amp is a star performer a
real artist it plays music and pleases the audience
listen reviewing from scHematic is out of question there needs to be abcd...etc
comparison, symasym is time to face the underdogs ska and aksa on the
sound stage
good luck to all competitors
cheers
Maybe someone start a thread "Symasym5 Amp - Listening impressions" ?
Yeah, I wonder how many folks we could get to review it without ever having heard it
------------------------------------------------------
subjective comparisons to ska,aksa,symasym abc lets see how they sound
or is it just pseudo hype they talk about, a good amp is a star performer a
real artist it plays music and pleases the audience
listen reviewing from scHematic is out of question there needs to be abcd...etc
comparison, symasym is time to face the underdogs ska and aksa on the
sound stage
good luck to all competitors
cheers
jmateus said:
Hi friend,
I listed my JBLs, not because I am devoted to them but because that is what I have. I got them for free except for the repairs I had to do to get them up and playing again. I am thankful for them. They are much better than I can afford.
I listed them to qualify my listening impression. I have never found the highs on the 4425's to be harsh. Nor did I call the highs of the Symasym harsh. They have always seemed weak to me due to the 16K limit. That is why I liked the Symasym with them. It seems strong enough in the highs to ballance that out.
I'm listening to them right now and I like what I hear. I guess everyone has their favorites.
Blessings, Terry
While waiting for my parts, I was playing with the case to see how to fit everything inside. And then came the grounding question. I will have a preamp and an amp in the case, each using its own transformer and supply. I suppose the best is to have every grounds related to the amp going to the middle point of the last caps of the amp power supply and every grounds related to the preamp going to the preamp power supply ? And then I would join the two star points ?
Like this ?
Like this ?
