| JinMTVT |
I already own a very very nice Rakk Dac
( that was recommend to me by you guys here! )
with passive output and their quality PS kit.
I use this one in my personal room
combined with my stereo system ( powered by a Bryston 4BST ) or my diy Headphone amplifier
( from our friend member Sjostrom in Sverige )
I am currently buying stuff and designing my new HT room, and i will need alot of electronics to do so.
Right now i am looking for DAC kits that would give the best bang for the bucks, something of similar quality to the Original RAKK kit or better ...
The thing is that i will probably need 6 to 8 of them,
so the price needs to be right.
What other choices to we have (other than the original RAKK or the new RAKK Dac ..wich runs for some 500$/each with an output stage and PSU )
is there any kit available from a member here ?
i do not like hold-back stuff like non OS kits, or minimilazing kit ... the RAKK got all of the digital stuff on it and it just kicks *** ... ( never heard any non-os DAC sound as good neway .. )
thanks for your time :) |
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| analog_sa |
No match for Rakk Dac. As the web site proudly proclaims:
"Very simple design for begging DIYer" |
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| ezkcdude |
| quote: | Originally posted by JinMTVT
I already own a very very nice Rakk Dac
( that was recommend to me by you guys here! )
with passive output and their quality PS kit.
I use this one in my personal room
combined with my stereo system ( powered by a Bryston 4BST ) or my diy Headphone amplifier
( from our friend member Sjostrom in Sverige )
I am currently buying stuff and designing my new HT room, and i will need alot of electronics to do so.
Right now i am looking for DAC kits that would give the best bang for the bucks, something of similar quality to the Original RAKK kit or better ...
The thing is that i will probably need 6 to 8 of them,
so the price needs to be right.
What other choices to we have (other than the original RAKK or the new RAKK Dac ..wich runs for some 500$/each with an output stage and PSU )
is there any kit available from a member here ?
i do not like hold-back stuff like non OS kits, or minimilazing kit ... the RAKK got all of the digital stuff on it and it just kicks *** ... ( never heard any non-os DAC sound as good neway .. )
thanks for your time :) |
You can try my ezdac pcb. I have one board left at the moment. :) |
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| Extreme_Boky |
Thanks paba!! |
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| Ruach |
| You can try Pedja's TDA1541A PCB. |
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| JinMTVT |
sorry but i don't see why i/we would consider anything other than the pcm1794 or CS4398 as they both are
"flagship dacs" as stated on cirrus page
it's not like it costs 200$ for the chip itself
( usually less expensive than older rare NOS stuff nah?)
the point of getting a diy or kit dac is to get the best possible results with less $$$ than buying a 5000$
gold plated front plate commercial box
that beeing said,
from the very very nice list of "granodemostasa" over at headhifi, it really goes back to KandK audio for cost
VS quality .... gee
i thought that some people would have released something similar to the RAKK DAC, but in self assembled and less expensive ...
If i'd be to use RAKK DACs again,
would there be a way to make less expensive high quality output stage ?
and maybe a common power supply for all the dac boards? ( or is that a bad idea due to some crosstalk or whatever i do not know here.. )
i personally got the passive output with lundall tranfos,
i can say that it sounds just like it wasn't there
( hole point )
thanks all for ur time again :) |
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| David Davenport |
| quote: | Originally posted by JinMTVT
If i'd be to use RAKK DACs again,
would there be a way to make less expensive high quality output stage ?
and maybe a common power supply for all the dac boards? ( or is that a bad idea due to some crosstalk or whatever i do not know here.. )
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You trade off cost for quality in the output stage. It would be possible to make an output stage similar to the RAKK dac Passive Output using less expensive transformers, however the quality would suffer.
It would be possible to create a common power supply for all of the boards. The biggest saving would be in the single versus multiple power transformers. I can’t say for sure but I speculate that the total capacitance would be the same in both cases so there would be no savings there. The individual rectifiers and regulators are not a big deal so you could use multiple of those to insure no crosstalk. So the design would be individual supplies sharing a single power transformer.
Dave |
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| JinMTVT |
| quote: | Originally posted by David Davenport
You trade off cost for quality in the output stage. It would be possible to make an output stage similar to the RAKK dac Passive Output using less expensive transformers, however the quality would suffer.
It would be possible to create a common power supply for all of the boards. The biggest saving would be in the single versus multiple power transformers. I can’t say for sure but I speculate that the total capacitance would be the same in both cases so there would be no savings there. The individual rectifiers and regulators are not a big deal so you could use multiple of those to insure no crosstalk. So the design would be individual supplies sharing a single power transformer.
Dave |
Nice advices , thanks for quick answer :)
What other options do we have for output stage?
active is probably alot more expensive ?
the Rakk Dac passive output consists of only 2 transformers ..i know that they are of top quality
but ain't 275$ a bit overkill for 2 small power transfos, 2 resistors and matchi pcb ?
it's the same cost as the DAC itself ..
i figure that 90% of the price of the passive output is the cost of the transfos
are lundahl transfos the best there is ?
any other high performance option on tranfos?
i mean ..this is really low power stuff nah ?
shouldn't it cost less than high power transforms? |
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| JinMTVT |
just on a side ...
can we say that the Rakk Dac Mark 2 wich is supposed to be better than their first version,
constitutes the best performing DAC available for under 1000$ ??
i seems so judging from quality and components,
and from the list of available DACs... |
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| David Davenport |
| quote: | Originally posted by JinMTVT
What other options do we have for output stage?
active is probably alot more expensive ?
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Yes, the Active Output is substantially more expensive (and better sounding.) It uses the same transformers on the output as does the Passive Output, then there is a whole lot of additional stuff.
| quote: |
the Rakk Dac passive output consists of only 2 transformers ..i know that they are of top quality
but ain't 275$ a bit overkill for 2 small power transfos, 2 resistors and matchi pcb ?
it's the same cost as the DAC itself ..
i figure that 90% of the price of the passive output is the cost of the transfos
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You are right; the amorphous core transformers (and thus the output stages that use them) are expensive; a lot more than those that use the regular core material. And the amorphous core line level transformers are much less expensive than the amorphous core power output transformers.
Dave |
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| SamL |
| quote: | Originally posted by JinMTVT
I am currently buying stuff and designing my new HT room, and i will need alot of electronics to do so.
Right now i am looking for DAC kits that would give the best bang for the bucks, something of similar quality to the Original RAKK kit or better ...
The thing is that i will probably need 6 to 8 of them,
so the price needs to be right.
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Hi Jin,
I am interested to find out how you plan to use 6 to 8 DAC in HT? Do you have Dolby Digital/AC3 decoder with 6 digital output? |
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| JinMTVT |
Ok, if i understand correctly, the amorphous core is what gives it's price VS regular transfo
( an amorphous core doesn't use the same material as regular core? like silicone metal hybrid and stuff like
that ?? )
So we don't really have much choices when it comes down to quality then ..
So explain to me then, how all other DACs kits that doesn't seem to use such high quality Transfos as output, get out with good quality sound?
they all sound worse?
Most of the cheapest DACs and some more expensive on the liste we have here, don't look like they are using anything exotic for output stage ... i don't really understand now
SamL: Everything will be computer driven ..
i will never use any receiver whatsoever ..i don't understand the use of receivers nowadays when a computer that both plays HD video and audio and all music + librairy + games that will have the same sound quality and more upgrade options can be bought for rouhly the same money ... ( only my opinion .. )
Neway i'll probably try and find a controller that can accept multiple channnels from a digital source and split them up without introducins too much jitter and all
not there yet, but i know it can be done
i've also seen some pro cards with multiple digital output
that one can assign to each channel ( stereo digital outputs that can be used with dacs then ... )
of course if i use stereo Dacs it can reduce the total number required
not too sure about the setup yet
and i have not decided if digital crossovers will be used or not ....i have to see what is possible
( both software and sound card wise ) |
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| limono |
Hi
I own a Rakk Dac I, and I was using it with Erno Borbely J-fet output stage . I got and old Mcintosh MD7007 with Tda 1541 S1 silver crown .I updated this machine (clock ,filter , caps etc .) and switched the J-fet output stage to McIntosh .Well I think
the sound is comparable (maybe a tad smoother ) to Rakk Dac . I think that RakkDac is a great value but I like heaving just one box solution better. All dacs benefit from very good digital cables and great transport and those don't come cheap .Regards |
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| ezkcdude |
| The Rakk DAC is way overpriced. However, there are not too many DIY kits utilizing PCM1794, so maybe they take advantage. My ezdac board (see the website) is a very simple design using CS8416 (S/PDIF receiver)->AD1896 or SRC4192 (for asynchronous resampling/reclocking to 96 kHz)->PCM1794/8 (DAC)->passive resistor I/V->simple balanced-to-single-ended op amp buffer stage. All the regulation is done with simple LM317/337. AFAIK, it's the simplest DAC board out there that has PCM1794 and AD1896 (which is what I wanted). Needless to say it's a lot cheaper to build my ezdac than the RAKK (which I had looked into before). |
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| JinMTVT |
hi ezkcdude!!
i think i had overlooked your kit!
i hadn't notice that you'r using the 1794 chip!
Have you measured your DAC's performance?
compared with others?
how do you think it compares to Rakk unit?
( measurable things...i don't care about how sweet it sounds on a sunny afternoon :p )
What is the cost of your pcb board,
and tota cost for the best version ( 131$ is for all parts except the pcb ?? )
what exactly is used for output stage here, only direct active ops?
nice kit neway, i like how simple it looks!
and i always like to buy stuff from member of this community when possible :) |
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| David Davenport |
| quote: | Originally posted by JinMTVT
Ok, if i understand correctly, the amorphous core is what gives it's price VS regular transfo
( an amorphous core doesn't use the same material as regular core? like silicone metal hybrid and stuff like
that ?? ) |
Lundahl buys their cores from a supplier and the amorphous cores are a lot more expensive than the regular cores. They pass the cost difference through their distributors and in turn to the user. Several of the Lundahl transformers are available with a regular core or an amorphous core. They are the same except for the core. For example, the LL1660 and LL1660AM. The cost shown on the K&K Audio website for the LL1660 is $98 while the cost for the LL1660AM is $240. The LL1674, which is used on the RAKK dac Passive Output, is available only with an amorphous core.
| quote: | | So we don't really have much choices when it comes down to quality then .. |
Of course, there are lots of choices but there is no free lunch that I know of. There are other excellent transformers and they too are expensive. It is possible to build an excellent output stage without transformers – I have done it. However when the dust settled, the cost was about the same. I believe, and this is only a belief, but formed from years of experience, that it costs about the same to provide the same function and quality no matter how it is implemented. You get what you pay for.
Dave |
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| JinMTVT |
David : you seem very knowledgable about output stages ...
what is the benefit of a completly passive output stage then ? ( like the one offered for the RAKK DAC )
what is the benefit of an active with transfos ?
when i bought the Rakk Dac some years ago,
i actually thought that using passive output was giving us less power to work with but with higher quality
( untouched ) signal |
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| limono |
Sorry, but every product compared to strictly DIY will appear "way overpriced ".I consider Rakk Dac - cheap for what it does (even though myself can't afford Lundahl trans right now; ;0). The cheapest Erno Borbely's J-fet stage (board +Psu board) would be ~$500 and ultimate way over $1000. No tubes ,no transformers .The finished phono stage based on K&k design (also available as a DIY) run over $4K retail
and some still consider it a great value. You may have a look at ANUK transformer prices and still AN Kit 1 amp was called what "a bargain of the centaury"??? You know ,DIY is fine and great when you exactly know what you're doing and have some Electronic lab with test equipment at home or at least exposure to the best out there .So many times(almost always) DIY stuff sounds just pathetic ,but the owner/designer is so proud and happy that there is nothing to say. |
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| David Davenport |
Trade-offs in an active versus passive output?
It really has a lot to do with the whole system. Your observation of “…using passive output was giving us less power to work with but with higher quality ( untouched ) signal” is a good one. There will always be electronics down stream from the DAC and depending on the drive capability of the DAC and what the down stream electronics is and how it handles the signal will determine if you need an active output or can use a passive output. You can think of the active output as effective and appropriate electronics for the DAC to drive. The electronics can be designed to have greater drive capability than is available from the DAC chip. If the electronics is well done and coordinated with the DAC then it won’t hurt the sound and can enhance it.
So the benefit of the passive solution is fewer parts and lower cost. A passive output can be an excellent solution if it works well in your system.
The benefit of the active solution is potentially better sound. The active output is generally less system dependant.
With the RAKK dac Passive Output versus RAKK dac Active Output, the Active Output provides a little better life and sparkle to the music as will as a better presentation of the sound stage in every dimension.
The question of transformers is a separate issue. If you were to look at many of my designs, you might not believe it but I tend to be a minimalist – less is better. I will only add something if it provides a benefit. I have found (many times) that a transformer on the input or output of a circuit will help rather than hinder the performance of the circuit. I suspect that galvanic isolation is more important than we realize.
I don’t want to get into a religious war on which circuit topology is best and I’ll just say that I have had good results with transformer outputs.
Dave
P.S. I’m leaving for a long weekend at the beach so this will be my last post till Monday or maybe late Sunday. |
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| DougL |
I built a RAKK DAC Mark1 Right after the Mark 2 was announced.
I am currently running:
The RAKK DAC,
The RAKK DAC PS,
EDCOR 10k:600 interstage transformers.
As it sits, it is the best DAC I have ever heard. I had never heard a passive output, and wanted to try it without spending a lot of money. $25 seemed to be a lot less risky for something that seemed a bit different.
I will upgrade the transformers to the RAKK DAC passive output.
I'm just not in a hurry. I am really curious to hear the difference.
I will also upgrade to the Mark2 at some point. Kevin and Dave are excellent engineers and make a quality product.
Just My two cents.
Doug |
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| ezkcdude |
| quote: | Originally posted by JinMTVT
hi ezkcdude!!
i think i had overlooked your kit!
i hadn't notice that you'r using the 1794 chip!
Have you measured your DAC's performance?
compared with others?
how do you think it compares to Rakk unit?
( measurable things...i don't care about how sweet it sounds on a sunny afternoon :p )
What is the cost of your pcb board,
and tota cost for the best version ( 131$ is for all parts except the pcb ?? )
what exactly is used for output stage here, only direct active ops?
nice kit neway, i like how simple it looks!
and i always like to buy stuff from member of this community when possible :) |
I just looked at the K&K website again. I didn't realize there was a new version of the Rakk DAC with ASRC. Now they use the exact same chipset that I do. Interestingly, they don't mention anything about AD1896, but it is pin-compatible with SRC4192, so you could use either. It's still more expensive than my board (by quite a bit), but I can't argue with the design anymore, since it's pretty much exactly like mine. I do have a pet peeve though, in that it's not really much of a "kit". They pre-mount all the smt components. DIY should involve some major pain, right? :D
As for measurements, some others have done some measurements on my dac:
http://www2.kumc.edu/students/ezami.../haowu/1794.htm
http://www2.kumc.edu/students/ezami...07-04-06-1.html
I bought a sound card (EMU-1212M) to do the same, but I haven't quite figured out how to do it yet.
As for the Rakk DAC, I've never seen any measurements, but I sure would like to compare! |
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| JinMTVT |
| EZ : how much do you sell your pcb for? |
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| ezkcdude |
| quote: | Originally posted by JinMTVT
EZ : how much do you sell your pcb for? |
I'm not sure if I'm allowed to talk about that on here. If you send me an e-mail, I can tell you.
Edit: I read your first post again, and saw that you want to buy 6 boards! If that is the case, I can definitely do a special order. Just let me know. |
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| JinMTVT |
EZ: no prob i'll email you latter..
i'd start by 1 unit to compare it to my current RAKK dac just for fun of it ..
but thinking of it, i'll probably need more than 10 units
( building new house and i'll have to supply alot of sound to alot of different places in the house so;
but only the home theather won't be stereo ..everything else should be stereo thus requiring only 1 unit each)
Could you elaborate on your output stage ?
why have you choose this particular design
( minimum with op ?? )
have you tried with different options ? why no transfos? |
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| ezkcdude |
| quote: |
Could you elaborate on your output stage ?
why have you choose this particular design
( minimum with op ?? )
have you tried with different options ? why no transfos? [/B] |
You hit the nail on the head. It's the minimum that needed to be done for my "ez" design. I needed something with single-ended output, and the simple balanced-to-single-ended op amp converter is the simplest active design out there. Remember the I/V is actually done passively with the resistor, so the op amp is not doing I/V - just gain. Anyway, there is at least one person who has taken my board and simply populated the chips - and then used a different output stage. I certainly have no problem with that, and am not offended in the least. The way I see it - my board does a few things and does them well - and not too expensively. If you want to use different power regulation or output - those things are possible to.
As for using transformers - I have no plans to. They are a little too "boutique" for my taste. I can only compare my design to other DAC's I have had (Derek Shek, Theta Pro Prime IIa, and the SqueezeBox analog output) - I like mine.
The only thing I will warn you about is that if you are inexperienced with soldering (as I was when I started the project) - this dac can be tough to build. It really helps if you've had plenty of experience with smt debugging. |
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| JinMTVT |
i have confidence, and some experience with smd stuff..no problem for soldering ( well equipped with Hakko 936 and a myriad of small tools and tips :p )
What would you suggest could be improved without investing another 100$ on your output stage?
i'll send you an email for price and stuff..
thanks :) |
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