Just added a Bulgin 6A mains filter in an IEC socket to replace the standard mains inlet socket. Sounds better still - will be adding more shielding soon, will add pics and comment on sound quality in due course.......
The low mids still sound a bit "fuzzy" to me though.... (Although they are better than before.)
This is it now:
The low mids still sound a bit "fuzzy" to me though.... (Although they are better than before.)
This is it now:
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Hi everyone,
Since there has been lots of reference to Connexelectronics in this thread, I thought people might be interested to read a new review of Connexelectronics modules posted eariler today in the below thread:
http://www.diyaudio.com/forums/connexelectronic/178293-photo-gallery.html
I mention this here because the above new review is in a Photo Gallery thread where it may otherwise not be found by people looking for reviews (it includes a couple of photos also).
Since there has been lots of reference to Connexelectronics in this thread, I thought people might be interested to read a new review of Connexelectronics modules posted eariler today in the below thread:
http://www.diyaudio.com/forums/connexelectronic/178293-photo-gallery.html
I mention this here because the above new review is in a Photo Gallery thread where it may otherwise not be found by people looking for reviews (it includes a couple of photos also).
sorry v-bro, probably it's my mistake.. but to me this makes no difference.. if the second amplifier sounds better than the first.. as long as I don't hear the hiss from my seat.. I buy the second..
Until the day you buy some horn loaded speakers...trust me, you'll be sorry!
Well, there are some interesting new technologies, like the AD199x series amplifier chips, they sure do feature good specs...
Oh and since everyone is so interested in proof, here's two comparable resistors:
Low noise thin film:
PANASONIC|ERA6ARW102P|RESISTOR, 1K, 0.05%, 0805, 0.125W | Farnell Nederland
And it's noisy thick film cousin:
PANASONIC|ERJT06J102V|RESISTOR, ANTI PULSE, 0805, 1K | Farnell Nederland
Now look at the resemblance and the price difference!
$20 of parts, don't make me laugh!!
well, if you expect high quality sound, build high quality amps
might not be so hard
man, if I was to complain about every crappy amp I have built in my life, it would probably make my life miserable
I clearly remember one certain amp blowing
and it was a big and rather expencive build
acttually it went dead twice
and I blamed the designer/supplier
well, thinking about it numerous times, through the years, and learning a bit more
I now know it was probably my own fault
first time I think it may have blown because of a loose supply cap screw
I never forget that spark
really scary
I guess that could have hurt something related to stability
when replacing outputs, I forgot to inspect zobel on output
I suspect a non functioning zobel took it out the second time
a simple stupid mistake
what can i say, it took me more than 5 years to figure that out
remember LYNX amp ?
seems it got a bad reputation, and 'forgotten'
well, what was the problem
what really happened ?
I suspect fake components had been used by a few people
and that was the end of that
might not be so hard
man, if I was to complain about every crappy amp I have built in my life, it would probably make my life miserable
I clearly remember one certain amp blowing
and it was a big and rather expencive build
acttually it went dead twice
and I blamed the designer/supplier
well, thinking about it numerous times, through the years, and learning a bit more
I now know it was probably my own fault
first time I think it may have blown because of a loose supply cap screw
I never forget that spark
really scary
I guess that could have hurt something related to stability
when replacing outputs, I forgot to inspect zobel on output
I suspect a non functioning zobel took it out the second time
a simple stupid mistake
what can i say, it took me more than 5 years to figure that out
remember LYNX amp ?
seems it got a bad reputation, and 'forgotten'
well, what was the problem
what really happened ?
I suspect fake components had been used by a few people
and that was the end of that
Thanks von.ah - they are M3 bolts; the outer 4 mounting holes on the amp are not connected to GND (only the central mounting hole is connected to GND; which I'm not using.) I checked for continuity and it's ok.
I'm using Nylon spacers for the standoffs for the softstart and the PSU boards.
It can be 20k , or 47k....
I still hesitate between TA3020, TDA7293 BTL, and LME49810 with BJT
I didn't have bought yet, but I intend to use with a passive filter (~200hz LP ) with a woofer, so I need something with medium (~47k ) input impedance.
Well, whadda'ya know?! A cheap cable has gone a long way to sorting out the problems with this amp! I bought a cheap *** Cambridge Audio interconnect, here:
Cambridge Audio 1m Interconnect on eBay (end time 09-Apr-11 09:16:56 BST)
It seems to have almost sorted-out the "muddiness" in the lower mid ranges! And the interconnect I was using cost at least 6 x what I paid for this one!
There are of course, side effects - the upper mid range now is a bit emphasised, but I'd rather that than how it was!
Any suggestions for new speaker cable (biwire) greatfully recieved - I'm getting there slowly!
Cambridge Audio 1m Interconnect on eBay (end time 09-Apr-11 09:16:56 BST)
It seems to have almost sorted-out the "muddiness" in the lower mid ranges! And the interconnect I was using cost at least 6 x what I paid for this one!
There are of course, side effects - the upper mid range now is a bit emphasised, but I'd rather that than how it was!
Any suggestions for new speaker cable (biwire) greatfully recieved - I'm getting there slowly!
If cables make a difference your source output is the problem. Really, sound differences should not occur unless the output impedance is so high the LRC parasitic components of the cable and connectors become a filter in the relevant part of the audio band. Usually these filtering effects occur in the megaherz + band, not in the audio band.
An example is a passive guitar, where hundreds of meters of copper wire of the pick up form a very high output impedance. Here a few nanofarad capacitance for instance can form a lowpass filter and the high frequencies can start to sound dull and lifeless.
With active equipment ANY decently made cable should sound EXACTLY the same....
An example is a passive guitar, where hundreds of meters of copper wire of the pick up form a very high output impedance. Here a few nanofarad capacitance for instance can form a lowpass filter and the high frequencies can start to sound dull and lifeless.
With active equipment ANY decently made cable should sound EXACTLY the same....
Are u sure? And I thought this is a diy forum.
Changing the input cap is the most basic and easiest tweak to improve the sound.
Sorry, I prefer to encourage rather than discourage the diy community.
ChuckT:
For Class D/T sometimes additional care needs to be taken.
Class D/T amps produce a lot of EMI as an inherent part of their operation, primarily associated with the output stage switching.
Depending upon the size, inductance, position, orientation, and lead length of your replacement input AC coupling capacitor, you may inadvertently pick up output stage switching noise and introduce this back into the input of your amp - where it can be amplified further and lead to unwanted oscillations. This can lead to anything ranging from subtle sound quality degradation, through to substantial oscillations that may make the amp run hot or even damage amp components.
Hence, with Class D/T amps you need to take into account the above, in addition to the normal audio considerations associated with input capacitor sonic qualities.
Experimenting can be a lot of fun, and sometimes costly. Either way, knowing a little more about the possible implications of a change, before you make it, can be helpful - particularly when the implications may be costly and inconvenient for you (and the supplier of the amp).
'' I know for a FACT that Tripath amps are only linear when the load matches the configuration of the output filter well.''
this is true. *tripath data sheet says
This is especially important for applications where the end customer may attach
any speaker to the amplifier (as opposed to a system where speakers are shipped with the amplifier),
since speakers are not purely resistive loads and the impedance they present changes over
frequency and from speaker model to speaker model. An RC network, or “Zobel” (RZ, CZ) should be
placed at the filter output to control the impedance “seen” by the TP2050 when not attached to a speaker load. The TK2050 works well with a 2nd order, 80kHz LC filter with LO = 10uH and CO =
0.47uF and RZ = 10 Ohm/1W and CZ = 0.47uF.
NOTE: Output inductor selection is a critical design step. The core material and geometry of the
output filter inductor affects the TK2050 distortion levels, efficiency, power dissipation and EMI output.
this is true. *tripath data sheet says
This is especially important for applications where the end customer may attach
any speaker to the amplifier (as opposed to a system where speakers are shipped with the amplifier),
since speakers are not purely resistive loads and the impedance they present changes over
frequency and from speaker model to speaker model. An RC network, or “Zobel” (RZ, CZ) should be
placed at the filter output to control the impedance “seen” by the TP2050 when not attached to a speaker load. The TK2050 works well with a 2nd order, 80kHz LC filter with LO = 10uH and CO =
0.47uF and RZ = 10 Ohm/1W and CZ = 0.47uF.
NOTE: Output inductor selection is a critical design step. The core material and geometry of the
output filter inductor affects the TK2050 distortion levels, efficiency, power dissipation and EMI output.
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