anabella

'Ana, where do you see a DAC leading to an analog amp? There should be an A/D converter at the FRONT end, perhaps an op amp in the headphone section, but no D/A until just before the speaker terminals, and no analog amp'... im sorry, i did hugely oversimplify...and did also to some degree misspeak... if you open the unit...youll see a largish semi-enclosed section which holds a row of seven large blue capacitors, seven coils which are reminiscent of grub worms [im not kidding], and on the back of this enclosure, seven mofets numbered IRFI4024...this is the PWM... now, while PWM's are commonly called digital amps...in fact, their action is 100% analog...as is that of the mosfets...which lead directly to speaker output... this design, for audio purposes, first surfaced in the seventies...it as developed, i believe, in the sixties for other purposes... the mosfets switch output signals, using duration of switched impulses plus amplification to control the speakers....by themselves, mosfet switched amps are known for having a harsh sound...this harshness is commonly smoothed out through the use of filters...these filters act essentially as delays, and help fill in the gaps in sound created by the on/off aspect of the switches [mosfets]... ok...on to the dirty little secret.... while its said that PWM's convert digital signals directly into analog...this is not exactly true...PWM's react to to small voltage changes created by microprocessors [in this case TI digital 'amps'] as a result of receiving digital input...and in turn create 'speaker useful' amplitude based on their reading of these tiny voltage changes... DAC or no...a conversion from digital information to analog electical impulse does take place...as the two are obviously not the same, and analog is required to drive speakers as we know them.... it really doesnt matter if you include the microprosessors as part of the PWM or not...[physically, they are 'separate' on the panasonic, ie... not on the same circuit board]....a PWM is an analog amplifier, it handles analog signals...thats just a fact... im sorry if i caused this thread to veer off subject...but there did seem to be some question as to how digital amps work.... in my opinion, what we are seeing is the intrusion of the computer into what we call an amp...even as the old analog aspects remain central... i think i should mention the word...marketing....again... how does the amp sound?...ive only had it on for a few hours....but at this point, id say a little 'brittle'....although, im thinking it will mellow a bit with time... im not real happy with the bass, although i think i could get used to it....and to my ears, theres a bit of top end distortion...[i keep turning down the tone]... ive several sets of old slow speakers around, which i need to try it with....[the set im using are very high efficiency and are undoubtably accentuating everything]... id say...for the bucks, its pretty good.....not exactly musical, but very clear....definitely not something i would hook to a set of near-field studio monitors.......[or maybe i should?...ill have to think about that].... honestly, i think its the mosfet output i hear more than anything...those familiar with that type of amp may know what i mean... ana...

'In the meantime, what light does it shine on how the Panny gets output to speakers without a DAC?' i looked at the diagram...[which is very sketchy, and in some ways is utterly useless]... but basically the panny is collection of processors...leading to a DAC....leading to an analog amplifier... there is no mystery really...... what i find interesting is that the basic conception of the analog amplifier continues to rule by virtue of its undeniable utility ....the darned thing has revolutionized life-as-we-know-it over the last 100 years, and thats just a fact... truthfully, i dont think were that far removed from edison......'digital' simply being a matter of fine tuning basic electrical theory... as long as 'output' continues to be a matter of electrical modulation [in a very broad sense]....we are dealing with the samo samo.... aint nothing revolutionary here... which is not to say that i dont dream of a schematic i cant understand in terms of electrical theory... now that would be revolutionary.... ana...

bows to the experts... but i think you guys went a little technically overboard in answering the question... isnt it simply that USB protocol [in some ways, what is allowed to stream]...is NOT AT ALL the same thing as any given audio format...that format and protocol are as different as apples and ...uhmmm...horses? USB will stream any audio format supported by your software, at a rate dependent on that same software, and or equipment.. strictly speaking, electrical impulses flow through a USB connection...[thats me being a smart-ass, *bats eyelashes*]... ana...

RHA.... all of the programs mentioned have their pros and cons...sorry, but it really does come down to what sounds good and works best for you...[i definitely approve of having the ability to de-click by hand erasing the offending spike...but then the ability of the program to draw a detailed waveform would become important to me] while i love little apps that do one thing well, on the whole this sort of thing doesnt meet my needs...im used to having more options..... personally, i use a now out-dated, discontinued, two channel recording/mastering program [spark xl] exclusively for ripping...[this is not at all what the program was designed for]... i use it even though i know i can get better specs by running input through Logic pro or Pro tools [spark has a 96htz limitation, as does audacity].... i do this largely because i know the program very well, and ive always just flat-out liked the sound i get out of it... its the program i learned to master on...[big points for a certain nostalgia factor]... spark xl is my version of a 'little, easy to use, app'.... sorry im not more helpful...but i will say one shouldnt necessarily discount deejay programs....i used to use one for its 'on the fly' capability... ana..

interesting...i couldnt get the link to work...but i did look at a few other cement enclosures online... ive designed floating concrete shells meant to isolate studio monitors recessed into possibly resonant walls, but ive never seen anything like this... i guess i always assumed that a certain amount of cabinet resonance could be a 'mellowing' influence on a speaker, above and beyond any dampening material inside...in fact, im sure it is, or can be....i often design specific studio walls to be more resonant than others in order to absorb certain frequencies...[and i mean structurally resonant, with built in flex]... and of course concrete does resonate to some degree...but at a higher frequency than mdf... id think a concrete enclosure might create odd high frequency resonate tones if not completely dampened, which is probably impossible... sorry, just thinking as i type... that said, i have to say a little biased....my favorite speakers use a hand made 'tuned' cabinet for bass attenuation...theyre an old folded horn design, driven by single 6in full range ultra efficient drivers...i used to run them on 3W max class A tube monoblocs... theyre finicky things, have to be placed 'just so'....but acoustic bass in particular sounds like its being bowed or plucked right in front of you...utterly gorgeous at times... i guess i dont see the point of pretending one can completely do away with resonance...personally, i find it more interesting to attempt to use it....musically... but i am going to think about this... as i said before....interesting... ana...

"Virtually all click removal products butcher the sound to one degree or another. It never ceases to amaze me when people post files on the internet of the "before" and "after" effects of these products. They enthuse that the clicks have been removed but so has at least half the music!" yep and amen.... click removal programs work several different ways, but the two most common are 'spike removal' and hard limiting... in spike removal, clicks/spikes are 'recognized' on the basis of a normative algorithm which then simply deletes the offending spikes leaving a gap [which is supposedly not noticed, uh huh]....but the truth is that depending on the music and the algorithm used, you may lose more than just the click... hard limiting simply 'flat tops' the entire waveform...destroying the dynamic of the recording, effectively decreasing its 'loudness', and creating distortion...this is really a problem with a lot of newer recordings, as a great many of them are already flat topped/overly compressed [the result of a seemingly growing trend towards less-than-intelligent recording practices]... yes, if you have the software there are other ways to deal with clicking.... but, i have to say, in my opinion, youre at best simply degrading the recording, and at worst effectively re-mastering it by running any blanket de-click program... my advice is essentially the same as JonP's...[plus a more generalized bias against anti-click programs]...try different software...they do sound different...and some are bloody awful... hopefully you wont need or want a de-click program after finding something which suits you... ana...

just my two cents.... i like apogee products in general... ive no experience with the duet [absolutely, it has a very high cute factor]...but i know several folks who swear by their apogee mini DAC's...[which arent so cute...lol]... i personally rely heavily on their ensemble...i find it easy to use, has great sound, and its connectivity is marvelous...but then its 36 channel capability is beyond what most need...so no point in recommending it... i should also say that im very happy with their clock....it solved a number of problems for me... ana...

tim...i hope you dont think i was trying to put down your amp with my remark about marketing [i really meant something more along the lines of 'mass marketing' to the general public, as in trying to elicit a..'gee whiz, if its digital, then it must be better'....type response.. in fact, im very intrigued by the amp....the specs are great for the price.....i think i may just do as you suggest and send off for one.....i love experimenting...thanks for the links.. .................................................................................................................................................... markr...i play and collect a variety of out-dated [sometimes permanently out of tune] keyboard instruments...strange altered pianos, pump organs, harmoniums, accordians...even childrens toys... i play in a local band whose music is hard to describe...and do some session work for a couple of producers largely when they want to add a slightly disturbing off- kilter touch.. im actually a very good pianist...but ive a knack of sorts...i can play everything utterly wrong and still make it sound right...i think it has to do with being able to transpose according to a variable sense of pitch rather than key.... its a speciality thing...as one producer said to me, 'very few musicians are good enough to play so badly'....i prefer to take that as a compliment...

ahhhh... the confusion is mine....my apologies.. yes, i think i see the problem....... even though USB has an audio 'class', that class is 'exclusive'.....it will not recognize an amp....unless the amp has a built in sound card...or a sound card is hooked inline... there are amps which have direct USB connections....they include an internal sound card...and thus have a DAC built in...[theyre analog controlled]... plug your server right in... seems rather silly that a manufacturer of a 'purely' digital amp [not analog controlled] wouldnt provide the same connectivity... and software designed to bypass the problem.. maybe some do?....truthfully, im just curious, im a pretty hard core analog person...but the notion of a digital amp intrigues me....to some degree, because the 'digital' aspect appears, on one level, to be all about marketing...as even purely digital amps have a 'switched' analog output... and it is, of course, the output which matters... thanks for the welcome...im rather used to being one of the few females interested in this sort of thing... i'm an architect by trade...i design recording studios and listening rooms... im a musician...i also do a bit of mastering on the side, so have access to some exotic equipment and software...some consider that ive an 'ear'... i often deal with sound in formats which would fry a home system....

i'm a little surprised at some of the confusion apparent in the replies on this topic... you're quite correct that no external DAC is needed when using a digital amplifier, nor is there an internal DAC, per se, inside a digital unit. i'm not a tech person by nature, being more involved in acoustics...so my understanding of digital amps is limited... but, from what i understand....digital input signals are 'carried' via an internally introduced high frequency modulation index wave which is then translated into voltage and controlled on the output end via transistors...driving the speakers.. in this way, digital amps do act as 'one big DAC'... as with most analog amps, a feedback loop [or loops] is used to reference output to input in the hope of achieving zero variation between the two....[it seems easier to fine tune this loop using a digital signal...which perhaps accounts for the 'clarity' ascribed to these amps?]... i believe that one of the problems encountered is that the carrier signal has to be filtered out...and this is possibly harder to do than it seems without creating a slight out of phase condition, at least at certain frequencies... i'd be interested to hear your impressions of the set-up...