since you asked the same question ( yesterday ) :
http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1268523977
http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1268523977
suggestions for warm cd player
since you asked the same question ( yesterday ) : http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1268523977 |
I know what your problem is with the glare ... what causes it ... how to remedy it ... and can recommend SS CD players that this is not a problem with The problem is very real and a bit complex ... but I'm sure I can explain it to you and offer alternatives On loud passages you get a brief but distinct glare that is very short and annoying in duration ... on low level or medium level passages your player sounds wonderful and the glare is not present The glare is being caused by oscillation in the negative feed back loop of the analog output section of the CD player ... because the op amps can not deliver the required current to drive the capacitance of the interconnects on peak demands for current and keep the input signal balanced with the output signal in the negative feedback loop ... The lack of current on the peak demand causes an imbalance between the input and output signal in the negative feedback loop and results in a momentary or brief oscillation in the negative feedback circuit which causes a ringing for a very brief moment and produces a glare in the presentation When the peak demand for max current subsides, during low and medium passages ... and there is enough current being delivered by the op amps to the negative feedback loop to keep the input and output signal in balance ... the oscillation in the negative feedback loop and the ringing it generates subsides and the glare is gone Basically on loud passages that demand more current the small op amp chips can't generate enough current to maintain linearity and the by product is oscillation, ringing, and glare This is a very common problem that can be fixed a number of ways ... because most op amps are IC (integrated chips) with woefully inadequate on board power supplies ... you can find a modder who can up grade the IC op amp to a discrete op amp with much better power supplies ... Burson Audio comes to mind for this upgraded chip You can purchase a SS out board buffer which is a 1 to 1 no gain current divider that can handle this problem but will require an addition interconnect and power cord ... the B1 by Nelson Pass is an example of this Both these approaches may not be the most practical and a bit pricey for your situation Or you can look for a CD player that does not use IC type op amps and negative feedback in the analog out section but instead uses a Class A no negative feedback JFET transistor based analog out section The JFET's are very robust and can deliver the current needed to control the Interconnect's capacitance and because there is no negative feedback loop .. there is no chance of oscillation ... ringing ... and glare on peaks The Resolution Audio Opus 21 and the Ayre D1ex I use are two examples of JFET class A no negative feedback loop players ... I'm sure if you look you may find others and all this fits your requirement of NO TUBES ... which I agree with After hamming around with a few well panned mid price CD players I picked up a Denon 5000 in 2001 ... this player was much better than what I had been toying with but still had that annoying glare on the loud passages I attributed the glare to echo slap and comb filtering in my room and felt it was a room treatment issue I had to deal with On a lark I picked up a BV Audio SR10 outboard SS buffer to try just to improve the sound of my system not even think it would correct the glare issue ... which I still thought was room related ... and as soon as I installed the SR10 the Glare disappeared I did not equate that the BV piece would fix the glare ... but was just looking for further improvement in my system I definitely back into fixing the glare or you might says I stepped in $__t ... then my due diligent's enlighten me to what happened I have two BV SR10s that are sitting Idle now because my Ayre D1ex has the Class A no Negative feedback circuit and I'm off the CD merry go round I think the most practical thing for you to do is look for a player with one of these JFET type no feedback analog output section ... a used Opus 21 CD only or Ayre D1ex DVD player will run you about 2k and both these players have external outboard power supplies to boot |