Don't need full power - I'll be using 4 of these amps to feed my 4-way speakers. They're 105dB/Watt so I only need a fraction of a Watt from each amp!
Thhe MiniDSP amps I use to run were lowest distortion at 18V. Might play around with the V200 and see what sounds best.
I was running my "little" OB's (Seas Fa22RCZ) H1597-08 FA22RCZ
from a V200 fed with 18V from a TPS7A4700 Evaluation Module - TPS7A4700EVM-094 - TI Tool Folder (1 amp). Worked well!
Cheers,
Mike
Thhe MiniDSP amps I use to run were lowest distortion at 18V. Might play around with the V200 and see what sounds best.
I was running my "little" OB's (Seas Fa22RCZ) H1597-08 FA22RCZ
from a V200 fed with 18V from a TPS7A4700 Evaluation Module - TPS7A4700EVM-094 - TI Tool Folder (1 amp). Worked well!
Cheers,
Mike
Last edited:
Hi Camelator, did you have success using the Rapsberry Pi2 I2S output ?
I tried to cable it to input a QLS-QA100, but the issue is that using volumio (or Moode Player), it do not allow to use I2S output without attached device ... btw, how to "activate" the I2S output on a Rapsberry ?!?
Thanks !
I use the raspberry with an I2S DAC not with an amplifier, but I think it is the same.
There is many points to check:
To input QLS A100, you need to be sure QLSA100 is in slave mode. raspberry pi only works in master clock.
Then, if you don't see any I2S DAC in the parameters of Volumio, maybe you need a linux dedicated driver.
I think you need to configure the boot files as well, maybe try to find documents on hifiberry web shop
Thanks Mike. I'm just trying to get my head around the "all digital" concept and hoping that you and others can provide feedback on my line of thought.
What you are doing was what I had in mind when I bought the extra D802's but then it occurred to me that the minidsp volume control is probably pcm and that the audio signal would be degraded when attenuating the signal (noticeable or not I don't know). So to my thinking the volume control needs to be applied to the amps. From what I have read in the application notes for the chip in the d802 the volume is controlled by volume registers so it may be possible to control all amps from the one controller.
Am I on the right track or well off the mark?
regards Peter
What you are doing was what I had in mind when I bought the extra D802's but then it occurred to me that the minidsp volume control is probably pcm and that the audio signal would be degraded when attenuating the signal (noticeable or not I don't know). So to my thinking the volume control needs to be applied to the amps. From what I have read in the application notes for the chip in the d802 the volume is controlled by volume registers so it may be possible to control all amps from the one controller.
Am I on the right track or well off the mark?
regards Peter
Oki, thanks, yes the QA-100 works in slave mode without requesting MasterClk.
Will do search on driver/config in order to work directly from I2S output.
I've just been playing around with power supplies on the I.AM.D V200 amplifier and so far, the best sound is with a Connexelectronic SMPS300R followed by a Lundahl LL1694 choke in "serial connection for improved common mode rejection".
http://www.lundahl.se/wp-content/uploads/datasheets/1694.pdf
Very happy. Biggest improvement is on acoustic instruments, removed the slightly artificial sound, now very natural. Love CLC supplies!
Also tried some WBT banana plugs, replacing the bare wire connections - thinking it would make it easier to change out the amp every time I "upgrade" it
However the sound is noticeably worse. I don't think that Class D amps like heavy speaker wires or connectors. So back to bare wire connections.
(I'm running Kimber TCSS twisted pair hookup wire as speaker cable, like it a lot, and the tight twisted pair minimises the RF pollution when running without output filters)
OK back to listening.
Might proto up a linear PSU later, transformer - LCLC supply; already modelled it up in the Duncan's Amp PSUD modelling software. 28V transformer/LL1694/8200uF/LL1694/8200uF gives 23V with 1mV ripple and great load characteristics.
PSUD2
Cheers,
Mike
http://www.lundahl.se/wp-content/uploads/datasheets/1694.pdf
Very happy. Biggest improvement is on acoustic instruments, removed the slightly artificial sound, now very natural. Love CLC supplies!
Also tried some WBT banana plugs, replacing the bare wire connections - thinking it would make it easier to change out the amp every time I "upgrade" it
However the sound is noticeably worse. I don't think that Class D amps like heavy speaker wires or connectors. So back to bare wire connections.
(I'm running Kimber TCSS twisted pair hookup wire as speaker cable, like it a lot, and the tight twisted pair minimises the RF pollution when running without output filters)
OK back to listening.
Might proto up a linear PSU later, transformer - LCLC supply; already modelled it up in the Duncan's Amp PSUD modelling software. 28V transformer/LL1694/8200uF/LL1694/8200uF gives 23V with 1mV ripple and great load characteristics.
PSUD2
Cheers,
Mike
Oh and before I forget, the LL1694 is too big to fit in the I.AM.D LPS200 case with the SMPS300R.
(So I'm running the LL1694 spliced into the DC power cable between the LPS200 case and the V200.)
However the smaller LL2751 would fit. This would be a great tidy setup for a low-power or tweeter amp.
(So I'm running the LL1694 spliced into the DC power cable between the LPS200 case and the V200.)
However the smaller LL2751 would fit. This would be a great tidy setup for a low-power or tweeter amp.
I've just been playing around with power supplies on the I.AM.D V200 amplifier and so far, the best sound is with a Connexelectronic SMPS300R followed by a Lundahl LL1694 choke in "serial connection for improved common mode rejection".
http://www.lundahl.se/wp-content/uploads/datasheets/1694.pdf
Very happy. Biggest improvement is on acoustic instruments, removed the slightly artificial sound, now very natural. Love CLC supplies!
Also tried some WBT banana plugs, replacing the bare wire connections - thinking it would make it easier to change out the amp every time I "upgrade" it
However the sound is noticeably worse. I don't think that Class D amps like heavy speaker wires or connectors. So back to bare wire connections.
(I'm running Kimber TCSS twisted pair hookup wire as speaker cable, like it a lot, and the tight twisted pair minimises the RF pollution when running without output filters)
OK back to listening.
Might proto up a linear PSU later, transformer - LCLC supply; already modelled it up in the Duncan's Amp PSUD modelling software. 28V transformer/LL1694/8200uF/LL1694/8200uF gives 23V with 1mV ripple and great load characteristics.
PSUD2
Cheers,
Mike
Hi Mike,
Thanks for the feedback.
Eventually, received a good quality tcxo from China and it makes a big difference between the low cost/low value crystal from Conrad.
Music seems to be clearly more involving
Will try a good PSU on the tcxo next week...and a LL1694 but that would be later.
Cheers
Olly
Last edited:
Hello Olly and all others,
I follow this subject here since the french audiophile's forum is closed.
I'm very interested about adding good quality tcxo.
Could you explain, with some pictures if possible, all the mods you've done on your v200 and give the reference of your new tcxo (and where to buy it)
Many thanks,
Etienne
Hi Olly
What frequency is the tcxo and did you just swap the xo? Please share the site where you got it from.
I've ordered my v200 and getting my linear psu and other parts ready while waiting for the amp to arrive.
cheers
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.