Fasteddy,
Aftyer having read some of the forums over at SLIMP3, the general consensus seemed to be that the best bang for the buck in terms of mods was upgrading the power supply. I did not chnage any of the caps on the main board or even the caps on the elpac board. I only replaced the standard walwart with a higher grade Elpac 5v. The housed the elpac SMPS inside thye case alongside the gainclone toroids. All feed of the same AC socket. The sound over the stock is a little more improved, better control a little more base, nothing crazy though. I will post photos' if you want. I seem to remebber buying it from Mouser:
http://www.mouser.com/search/Produc...-1&Mpc=Elpac+External+Power+Supply&Mpcn=68001
Danon,
Thanks for the compliment and remebering the DIY paradise unit i built earlier in the year. To be quie honest i am not entirely thrilled with the sound quality of teh LM3875 yet. The sound of the gainclone NOSDAc combination is definitly cleaner with less coloration than the Charlize / Bel canto that i was running before (some may call that sound analytical i call it honest). However I am having issues with volume (doesn't play that load- not enough gain) and the sound still strikes me as being very closed in.
I think the closed in issue probably can just be put down to break in time. I am going to build a buffer (again from Peter) in the hope that it will help. What perturbs me more, and perhaps you or someone else can shed more light on this is the issue of volume... there aint much of it. All the voltages check out; 35 on the rails and a balanced 12mV across the speaker posts. I suspect it has something to do with the output of the DAC something i hope the buffer will help with. After the buffer is in i will be in more of a position to draw a comparison between the LM3875 and the T-amp.
I will definitley post my results
Aftyer having read some of the forums over at SLIMP3, the general consensus seemed to be that the best bang for the buck in terms of mods was upgrading the power supply. I did not chnage any of the caps on the main board or even the caps on the elpac board. I only replaced the standard walwart with a higher grade Elpac 5v. The housed the elpac SMPS inside thye case alongside the gainclone toroids. All feed of the same AC socket. The sound over the stock is a little more improved, better control a little more base, nothing crazy though. I will post photos' if you want. I seem to remebber buying it from Mouser:
http://www.mouser.com/search/Produc...-1&Mpc=Elpac+External+Power+Supply&Mpcn=68001
Danon,
Thanks for the compliment and remebering the DIY paradise unit i built earlier in the year. To be quie honest i am not entirely thrilled with the sound quality of teh LM3875 yet. The sound of the gainclone NOSDAc combination is definitly cleaner with less coloration than the Charlize / Bel canto that i was running before (some may call that sound analytical i call it honest). However I am having issues with volume (doesn't play that load- not enough gain) and the sound still strikes me as being very closed in.
I think the closed in issue probably can just be put down to break in time. I am going to build a buffer (again from Peter) in the hope that it will help. What perturbs me more, and perhaps you or someone else can shed more light on this is the issue of volume... there aint much of it. All the voltages check out; 35 on the rails and a balanced 12mV across the speaker posts. I suspect it has something to do with the output of the DAC something i hope the buffer will help with. After the buffer is in i will be in more of a position to draw a comparison between the LM3875 and the T-amp.
I will definitley post my results
n_k - thanks for continuing the discussion in a separate thread and your frank remarks.
A propos volume level: I can only report the anecdotal evidence I've come across. If memory serves, the current host of popular non-os dacs such as the nixon dackit, diyparadise's monica, audiosector's dac all have passive output stages. Many, besides yourself, have observed that their output may be insufficient to optimally drive an amp directly. So much for anecdotal corroboration.
I suppose the thing to do is to seek out some intermediary line stage, buffer, preamp etc, to provide gain. I haven't investigated here. Offhand maybe the kookaburra preamp from twisted pear audio, rolled with AD8620 opamps ...?
Alternative possibility: a dac with an active output stage. Perhaps something along the lines of the dac-ah: I believe its output stage is sufficient even to drive headphones.
Aside - before your gainclone clone is superceded (usurped?) by anything else, might I suggest - if not yet done - rolling its input caps? In the longish "Charlize, my thoughts" thread I reported my cursory observations with a handful of different caps. In short, after marvelling at your work with the gcc, I thought it would be a pity not to explore some simple but (very) effective optimization of the diyparadise amp. Even more so should a comparison to the gc be upstream.
A propos volume level: I can only report the anecdotal evidence I've come across. If memory serves, the current host of popular non-os dacs such as the nixon dackit, diyparadise's monica, audiosector's dac all have passive output stages. Many, besides yourself, have observed that their output may be insufficient to optimally drive an amp directly. So much for anecdotal corroboration.
I suppose the thing to do is to seek out some intermediary line stage, buffer, preamp etc, to provide gain. I haven't investigated here. Offhand maybe the kookaburra preamp from twisted pear audio, rolled with AD8620 opamps ...?
Alternative possibility: a dac with an active output stage. Perhaps something along the lines of the dac-ah: I believe its output stage is sufficient even to drive headphones.
Aside - before your gainclone clone is superceded (usurped?) by anything else, might I suggest - if not yet done - rolling its input caps? In the longish "Charlize, my thoughts" thread I reported my cursory observations with a handful of different caps. In short, after marvelling at your work with the gcc, I thought it would be a pity not to explore some simple but (very) effective optimization of the diyparadise amp. Even more so should a comparison to the gc be upstream.
Adding a Burson Audio buffer to either my DacKit or Charlize made one of the biggest improvements to the system that I have experienced!
As stated, the outputs of these NOSDacs are passive so I would always recommend an active stage between them and the power amp, preferably with some gain.
Of course, a lot depends on the speakers used but I find even with efficient speakers, a NOS DAC, no gain stage, typical power amp, does not have enough oomph.
Danon, thanks for the great response
1. Well i can certainly add to the anecdotal experience... NOSDAC + LM3875 = not enough oomph, gain what ever. I will build the buffer in the next few weeks and report back. I am hopeful. Funny i was just reading the lengthy Russ White "twisted pair" posts las tnight
2. I recall your feedback re inpout caps and charlize. Thanks fro reminding me. I am definitley going to pursue that. To avoid having to read the 10,000+ posts under Charlize my thoughts would you mind recapping your observations. Either post here or ping me directly. Thanks for the encouragment and kind words.
Nuuk,
Would you mind telling more about the Burston audio buffer and Charlize
1. Well i can certainly add to the anecdotal experience... NOSDAC + LM3875 = not enough oomph, gain what ever. I will build the buffer in the next few weeks and report back. I am hopeful. Funny i was just reading the lengthy Russ White "twisted pair" posts las tnight
2. I recall your feedback re inpout caps and charlize. Thanks fro reminding me. I am definitley going to pursue that. To avoid having to read the 10,000+ posts under Charlize my thoughts would you mind recapping your observations. Either post here or ping me directly. Thanks for the encouragment and kind words.
Nuuk,
Would you mind telling more about the Burston audio buffer and Charlize
Neil,
What speakers are you using?
Regarding the buffer, indeed, when I was using it with Placette RVC that was placed directly at amp's input (buffer at DAC's output) I also experienced improvement in every aspect of DAC's performance. The buffer is based on a circuit used in Levinson ML30.6, ML360S processors, schematic attached (output imp 6ohm).
When using DAC with ML diamond buffer, it may be a good idea to replace 4.7uF BG N DAC coupling caps with smaller value film caps (as the buffer impedance is very high, coupling caps values as low as 0.1uF are fine).
People reported very good results with Hovlands 0.22uF, SCR 0.1uF. I was using teflon V-Caps 0.1uF.
What speakers are you using?
Regarding the buffer, indeed, when I was using it with Placette RVC that was placed directly at amp's input (buffer at DAC's output) I also experienced improvement in every aspect of DAC's performance. The buffer is based on a circuit used in Levinson ML30.6, ML360S processors, schematic attached (output imp 6ohm).
When using DAC with ML diamond buffer, it may be a good idea to replace 4.7uF BG N DAC coupling caps with smaller value film caps (as the buffer impedance is very high, coupling caps values as low as 0.1uF are fine).
People reported very good results with Hovlands 0.22uF, SCR 0.1uF. I was using teflon V-Caps 0.1uF.
Neil_Kaye, great concept, fine execution.
SqueezeBox as pre-amp:
? I suppose your completed device is entirely under WiFi wireless remote computer control (absence of knobs, no EtherNet port, etc.) ?
? My personal SqueexeBox is hard wire connected via EtherNet cable and RCA/analog connected to an older integrated amp, controlled by LAN/computer. Your experience regarding WiFi wireless verses EtherNet direct connect would be of interest. ?
? Your experience and listening impressions regarding SqBx analog verses optical / coaxial digital to amp would be of great interest. ?
? The SqBx DAC is 24 bit through analog ports, but the DDC is "LossLess" through SPDIF ports ... Any noticable differences, problems, questions ?
? Are you going to add this one to your other interesting projects at your web site ?
? It appears that the entire case is plastic of some sort, yes ?
? Do the heat sinks physically connect to the case ... no ventilation (?), any problems there ?
SqueezeBox as pre-amp:
? I suppose your completed device is entirely under WiFi wireless remote computer control (absence of knobs, no EtherNet port, etc.) ?
? My personal SqueexeBox is hard wire connected via EtherNet cable and RCA/analog connected to an older integrated amp, controlled by LAN/computer. Your experience regarding WiFi wireless verses EtherNet direct connect would be of interest. ?
? Your experience and listening impressions regarding SqBx analog verses optical / coaxial digital to amp would be of great interest. ?
? The SqBx DAC is 24 bit through analog ports, but the DDC is "LossLess" through SPDIF ports ... Any noticable differences, problems, questions ?
? Are you going to add this one to your other interesting projects at your web site ?
? It appears that the entire case is plastic of some sort, yes ?
? Do the heat sinks physically connect to the case ... no ventilation (?), any problems there ?
Peter,
I am driving a Jordan 92's in a transmission line enclosure. The db rating is arounf 88 and the speakers are 4-5 ohms.
http://web.mac.com/noteldov/iWeb/DI...cts/B6A9F293-40AA-4D01-A250-5427951E0B11.html
Where is a good site to purchase the coupling caps... and which are the coupling caps?
Are the repalcements caps also orientation sensitive like the BG's?
Fast Eddy i will get back to you onthe SB3, as i have a lot to say
I am driving a Jordan 92's in a transmission line enclosure. The db rating is arounf 88 and the speakers are 4-5 ohms.
http://web.mac.com/noteldov/iWeb/DI...cts/B6A9F293-40AA-4D01-A250-5427951E0B11.html
Where is a good site to purchase the coupling caps... and which are the coupling caps?
Are the repalcements caps also orientation sensitive like the BG's?
Fast Eddy i will get back to you onthe SB3, as i have a lot to say
The coupling caps are C13 and C14 on DAC board. Supplied are 4,7uF BG N and they work fine when DAC is on its own. With buffer present, some people reported that smaller film caps may be better.
Since I'm shipping your package today, I can include some caps for you to try (Hovlands, Axon, MIT, ERO, RIFA). If you choose something, you may pay for that later and send back the rest.
Two places to buy caps are percyaudio.com and partsconnexion.com
All caps are usually sensitive to orientation because of inner/outer foil arrangement.
Since I'm shipping your package today, I can include some caps for you to try (Hovlands, Axon, MIT, ERO, RIFA). If you choose something, you may pay for that later and send back the rest.
Two places to buy caps are percyaudio.com and partsconnexion.com
All caps are usually sensitive to orientation because of inner/outer foil arrangement.
n_k, my "final ruminations" in charlize context are here.
To recap: Caps. Not to favor any manufacturers I didn't make any univocal recommendations for coupling caps. If reading between the lines however, my preference while understated, is clear. Other - besides upgrading caps it appears good sense also to solder the amp's spkr outputs to account for phase inversion. Such minor changes seemed rather disproportionate to the resultant improvement.
To recap: Caps. Not to favor any manufacturers I didn't make any univocal recommendations for coupling caps. If reading between the lines however, my preference while understated, is clear. Other - besides upgrading caps it appears good sense also to solder the amp's spkr outputs to account for phase inversion. Such minor changes seemed rather disproportionate to the resultant improvement.
Fast Eddy,
1. The device is completely wireless controled either from a remote or my Mac. My entire music collection is housed on the Mac (with appropriate backups of course). All music was encoded as either Flac or apple lossless
2. There is absolutley no difference in sound qulaity between ethernet and wireless. I do run the wireless in "g" which permits up to 56Mbs transfer rate, more than enough for audio data. I have yet to have a dropped connection.
3. The SB3 i feel, falls quite short in regards to its analog outs. Bolder cables offers a Mod to improve the analog outs but i personally feel you are better off choosing your own DAC and using the SPDIF out on the SB3. I have been extremely happy using an outboard DAC; first a modded Bel Canto and now Peter's NOSDAC. I would definitly encourage you to experiment in this arena. The sound really does improve. I think even upgrading the power supply on the SB3 would help the analog outs.
4.Next week i am off for some sun, but when i get back i should have some more time to update my website. I was also going to wait until i have completed the buffer section and given the caps a chance to burn in.
5. The case is aluminum, bead blasted and black anodized
6. I tapped the heat sink to bolt directly to the chassis. The top and bottom of the chassis are vented. I ran the amp for several hours at 90% and although warm, i imagine the chips were doing fine. The heatsink are 1" thick aluminum, i find it takes awhile for the LM3875 in a vented case to heat these up
1. The device is completely wireless controled either from a remote or my Mac. My entire music collection is housed on the Mac (with appropriate backups of course). All music was encoded as either Flac or apple lossless
2. There is absolutley no difference in sound qulaity between ethernet and wireless. I do run the wireless in "g" which permits up to 56Mbs transfer rate, more than enough for audio data. I have yet to have a dropped connection.
3. The SB3 i feel, falls quite short in regards to its analog outs. Bolder cables offers a Mod to improve the analog outs but i personally feel you are better off choosing your own DAC and using the SPDIF out on the SB3. I have been extremely happy using an outboard DAC; first a modded Bel Canto and now Peter's NOSDAC. I would definitly encourage you to experiment in this arena. The sound really does improve. I think even upgrading the power supply on the SB3 would help the analog outs.
4.Next week i am off for some sun, but when i get back i should have some more time to update my website. I was also going to wait until i have completed the buffer section and given the caps a chance to burn in.
5. The case is aluminum, bead blasted and black anodized
6. I tapped the heat sink to bolt directly to the chassis. The top and bottom of the chassis are vented. I ran the amp for several hours at 90% and although warm, i imagine the chips were doing fine. The heatsink are 1" thick aluminum, i find it takes awhile for the LM3875 in a vented case to heat these up
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.