Thanks!
Do you you mean german "lärmen"? Maybe tomorrow evening a first power on seems to be possible......
Eight in a row - let 'm row.
2 more pictures answering the question: "Does it fit?"
BR, Toni
Attachments
SystemD LiteAmp running bridged:
Listening tests successfully completed.
A comment of an audiophile listener: very analytic
IMHO: Very clear and exact sound reproduction.
I have used my own designed gain amplifier. Attached the simple circuit to get the liteAmp running in bridged mode. The bridged amplifiers have an output zobel 47nF/4.7R connected between the speaker outputs to short circuit/reduce HF from outside.
Setup for bridging mode to get best SNR was:
THX Markus aka Chocoholic for this good sounding amplifier.
BR, Toni
Listening tests successfully completed.
A comment of an audiophile listener: very analytic
IMHO: Very clear and exact sound reproduction.
I have used my own designed gain amplifier. Attached the simple circuit to get the liteAmp running in bridged mode. The bridged amplifiers have an output zobel 47nF/4.7R connected between the speaker outputs to short circuit/reduce HF from outside.
Setup for bridging mode to get best SNR was:
- short circuit inputs to signal ground at gain amplifier
- remove extra output zobel 47nF/4.7R between speaker outputs
- pre-tune all amplifier modules to a switching frequency of about 380kHz.
- add extra output zobel 47nF/4.7R between speaker outputs and add 8R dummy load
- retune one amplifier in small steps to get lowest SNR.
- re-check switching frequency to be around 380kHz
THX Markus aka Chocoholic for this good sounding amplifier.
BR, Toni
Attachments
Hi Toni,
that's an impressive build! My congratulations !
Also I am glad that you are enjoying the sound.
... the audiophile listener - this wasn't you, right?
Are you not an audiophile listener?
Personally I heard the description analytic already for amps
which liked very much:
Giving you the perception of nothing messed, but vital presentation of details.
On the other hand I also heard the description analytic for amps which I disliked:
Cold and dead. Like something had sucked out all the live from the music.
Hope the audiophile listener's impression of the LiteAmp was more of the first type.
Markus
that's an impressive build! My congratulations !
Also I am glad that you are enjoying the sound.
... the audiophile listener - this wasn't you, right?
Are you not an audiophile listener?
Personally I heard the description analytic already for amps
which liked very much:
Giving you the perception of nothing messed, but vital presentation of details.
On the other hand I also heard the description analytic for amps which I disliked:
Cold and dead. Like something had sucked out all the live from the music.
Hope the audiophile listener's impression of the LiteAmp was more of the first type.
Markus
Thanks!
Thanks too!
Hopefully I am an audiophile listener too. But it is always better to have an opinion from "outside"....
Are you not an audiophile listener?
Of course first type!
BR, Toni
Guys,
I'm really struggling obtaining WIMA Polypropylene capacitors locally and having issues even getting them into the country because "I don't meet the minimum order quantity", the other disappointing issue is, suppliers like RS Components only stock a limited range of WIMA FKP, MKP and MKP2 values and they cannot even get me on special order MKP2 250VDC C23,C26 330nF and 220nF as they are "catalogue based" bah!
Can I use another brand of polystyrene capacitor? If so which would you recommend.
This is my local supplier. (Please note they list WIMA but they unable to get the values I requested need)
Products
Can anyone comment what the issues are if I don't use the WIMA brand.
I'm really struggling obtaining WIMA Polypropylene capacitors locally and having issues even getting them into the country because "I don't meet the minimum order quantity", the other disappointing issue is, suppliers like RS Components only stock a limited range of WIMA FKP, MKP and MKP2 values and they cannot even get me on special order MKP2 250VDC C23,C26 330nF and 220nF as they are "catalogue based" bah!
Can I use another brand of polystyrene capacitor? If so which would you recommend.
This is my local supplier. (Please note they list WIMA but they unable to get the values I requested need)
Products
Can anyone comment what the issues are if I don't use the WIMA brand.
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RS components: already, confirmed even sent an email with response advising me, they cant get it for me.
"We cannot match products suitable to your current request. The reason for this is that the product you are looking for is not part of the RS Components product range. We do not source as we are catalogue based."
Mouser: Shipping to SA, $60 (Not going to happen)
Farnell/Element14: Minimum Order between, 5 and 10. here is my local proxy supplier price. uhmmm these prices seem like a rip off to me.
WIMA FKP2D001001D00JSSD CAP, FILM, PP, 100PF, 100V, RAD @ R5.05, $0,43 ea excl 5-7 days moq 10
WIMA FKP2C014701D00JSSD CAP, FILM, PP, 4.7NF, 63V, RAD @ R6.77, $0,58 ea excl 5-7 days moq 10
WIMA FKP2D011001D00HSSD CAP, FILM, PP, 1NF, 100V, RAD @ R5.83, $0,50 ea excl 5-7 days moq 10
WIMA FKP2O100471D00JSSD CAP, FILM, PP, 47PF, 63V, RAD @ R7.63, $0,65 ea excl 5-7 days moq 10
WIMA MKP2F033301M00KSSD CAP, FILM, PP, 330NF, 250V, RAD @ R16.06, $1,37 ea excl 5-7 days moq 10
WIMA MKP1F032204D00JSSD CAP, FILM, PP, 220NF, 250V, RAD @ R12.70, $1,08 ea excl due end april moq 10
Digikey.. don't seem to find anything on there website.
In principle: you can use any PP type as long as it will fit on the pcb and have the voltage/ripple current spec like the WIMA types...
There are many other vendors which have polypropylene capacitors in their portfolio like AVX, Cornell Dublier, Kemet, EPCOS, Panasonic, TDK, Vishay.
Maybe you can use also some other NP0/C0G types for 47pF, 100pF ...
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Hi Reactance,
in case you really cannot get the missing parts or reasonable substitutes, we have to double check how I could support you in this case of emergency. Please contact me for this by e-mail.
It would definitely be a shame to see your project getting killed by unavailibilty of components....
in case you really cannot get the missing parts or reasonable substitutes, we have to double check how I could support you in this case of emergency. Please contact me for this by e-mail.
It would definitely be a shame to see your project getting killed by unavailibilty of components....
Hi Reactance,
seems like you have good luck.
On the pages of your local supplier I found suitable parts:
100pF:
FKP2D001001D00KSSD - CAP POLYPROP 100pF 100V 5
1nF:
FKP2D011001D00KSSD - CAP POLYPROP 1nF 100V 5
4.7nF:
MEB0.0047UF250V-J-P5 - CAP POLYESTER 4.7nF 250V 5
47pF:
47PHU - CAP POLY AXL 47pF 630V (placed vertically, long wire towards IRS2092)
or
12061A470J-MR - CAP CER SMD 1206 NPO 47pF100 (placed from bottom side)
330nF:
MKT1813433255 - CAP POLY AXL 330nF 250VDC (placed vertically)
220nF you can change to 330nF and readjust L1 to 12uH
MKT1813433255 - CAP POLY AXL 330nF 250VDC (placed vertically)
For C26, C25, C24 place the long wires facing towards connectors for +V,-V,GND.
Put sleeving over long wires of C25 & C26
Adjustment of L1:
Put only 30 turns instead of 33 on the T106-2.
seems like you have good luck.
On the pages of your local supplier I found suitable parts:
100pF:
FKP2D001001D00KSSD - CAP POLYPROP 100pF 100V 5
1nF:
FKP2D011001D00KSSD - CAP POLYPROP 1nF 100V 5
4.7nF:
MEB0.0047UF250V-J-P5 - CAP POLYESTER 4.7nF 250V 5
47pF:
47PHU - CAP POLY AXL 47pF 630V (placed vertically, long wire towards IRS2092)
or
12061A470J-MR - CAP CER SMD 1206 NPO 47pF100 (placed from bottom side)
330nF:
MKT1813433255 - CAP POLY AXL 330nF 250VDC (placed vertically)
220nF you can change to 330nF and readjust L1 to 12uH
MKT1813433255 - CAP POLY AXL 330nF 250VDC (placed vertically)
For C26, C25, C24 place the long wires facing towards connectors for +V,-V,GND.
Put sleeving over long wires of C25 & C26
Adjustment of L1:
Put only 30 turns instead of 33 on the T106-2.
The instructions make sense.
what is the new filter characteristics with the x2 330nF with L at 30 turns ?
Many thanks for the help.
Originally the LC was 0.77uF and 15uH, giving a double pole at 46.8kHz.
Now it is 0.99uF and 12uH, giving a dual pole at 46.2kHz.
==> Dual pole remains almost identical. The zero in the feedback network will work fine as it is.
The slightly lower impedances of the new filter would cause a slightly stronger peaking of the filter in a prefilter feedback, but are no issue in this postfilter design. Filter peaking is catched by the feedback and the change will be visible only in the bode plot as a minor increase of loop gain at 46kHz...47kHz and is easily in the trouble free zone.
See datasheet: 9.4 A RMS (continuous!) will rise the temperature 40 degrees above ambient. Audio has a crest factor of about 10% compared to a sine wave. So don't think this inductor will "melt down".
BR, Toni
Attachments
Hi Steve,
you will need the gain stage and main board.
Full data set of the gain board including limiter fully given in posting #160.
In case you do not want to have the limiter, you can simplify the
gain board a lot. Simply do not place the NSL-32 and also not the TL074 and everything in the circuit block around the TL074 (approx. the 1/3 of the entire page on right hand side of the schematic from posting #160)
For the mainboard there is the BOM and some PCB views in posting #161.
Schematic of the main amp is published in posting #224.
you will need the gain stage and main board.
Full data set of the gain board including limiter fully given in posting #160.
In case you do not want to have the limiter, you can simplify the
gain board a lot. Simply do not place the NSL-32 and also not the TL074 and everything in the circuit block around the TL074 (approx. the 1/3 of the entire page on right hand side of the schematic from posting #160)
For the mainboard there is the BOM and some PCB views in posting #161.
Schematic of the main amp is published in posting #224.