...listening compare PM Marantz PM6006
I compared the last view days a new (now its burned/run in) -Marantz PM6006 its an integrated amp with, remote motor potentiometer, DAC inside, Spekersa A+B , source direct, Phono MM/MC - its excellent made and this about 340 euro.
so no on and off pop- like the LM1875
technical data:
45Watt at 8R - 60W at 4R , with total 0,08% THD
inside are 100000µF /63V nichicon caps - so supply will be about 50V or so
class AB configuration with C1883A/A1859A transistors + power transistors C4467/A1694
Sound:
an integrated amp about 340 euro with all luxury what you need at home:
sound very tonal, deeper controlled bass, voices clear but s,Z are notable, high hats are not nice
after burn in phase of 3x20 hours with 4 hours pause the sound gets better now
deepness ok. PM6006 through the vocals/ instruments more from back to the front - like the amp wants to "just throw it out"
the complete stage move 1-2m to the listener - this feels like some music comes more out of the speakers and not behind the speakers to give me a good 3D sound stage
it is a really nice amp - its very closed but the soundstage , high and instruments are not like my taste. he is more powerful and has a bit better bass not so super controlled but very good.
its closed but - my taste
2:1 for the LM1875
I compared the last view days a new (now its burned/run in) -Marantz PM6006 its an integrated amp with, remote motor potentiometer, DAC inside, Spekersa A+B , source direct, Phono MM/MC - its excellent made and this about 340 euro.
so no on and off pop- like the LM1875
technical data:
45Watt at 8R - 60W at 4R , with total 0,08% THD
inside are 100000µF /63V nichicon caps - so supply will be about 50V or so
class AB configuration with C1883A/A1859A transistors + power transistors C4467/A1694
Sound:
an integrated amp about 340 euro with all luxury what you need at home:
sound very tonal, deeper controlled bass, voices clear but s,Z are notable, high hats are not nice
after burn in phase of 3x20 hours with 4 hours pause the sound gets better now
deepness ok. PM6006 through the vocals/ instruments more from back to the front - like the amp wants to "just throw it out"
the complete stage move 1-2m to the listener - this feels like some music comes more out of the speakers and not behind the speakers to give me a good 3D sound stage
it is a really nice amp - its very closed but the soundstage , high and instruments are not like my taste. he is more powerful and has a bit better bass not so super controlled but very good.
its closed but - my taste
2:1 for the LM1875
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Hey Rabbitz,
I have that NAD (316BEE V2) right now. What did you dislike about it? Maybe its a speaker match thing, but I've liked what that little thing can do, though I will admit it lacks some bass.
-Joey
Amazing what you can get for 340eu, DIY amps are not cheap when you factor in all the bells and whistles.
Thanks for your feedback Chermann.
Im still waiting on the mailman to bring me my 1875s
if you try to get the "older" model PM6005 you pay 225 Euro !!!
According to some post i found the difference is just a secon optical input and a other design + other foot for the amp
chris
My mistake as I checked my records. It was a NAD C315BEE from 2008 and it had an edge to it which made things sound harsh. I had a few other NADs in the past.... 7220PE, 7020E, C730, C162... they were OK IIRC.
It wasn't a speaker thing as my expertise is in loudspeaker design and build where as DIY amps are a sideshow I fiddle with.
Peter
DIY amps are not cheap when you add up all the bits. I have only done it recently (after a long break) out of curiosity but have now built my last one.
The only issue is once you built a good sounding DIY amp, it's a long search to find a commercial amp that then satisfies.
i agree.. if we add all cost together (with housing) we will have costs about 140 euro with the LM 1875 kit/amp
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..parallel this kit to a 2xLM1875 ...
Hi
if you want to have a better current capability for 4 ohm load with this kit then read here my results.
https://www.diyaudio.com/forums/chi...ration-composite-amplifier-9.html#post6013653
chris
Hi
if you want to have a better current capability for 4 ohm load with this kit then read here my results.
https://www.diyaudio.com/forums/chi...ration-composite-amplifier-9.html#post6013653
chris
first experience with kit
Today i tested a first Ebay LM1875 kit.
So let me give my first (premature) impressions.
Hooked on the board to my SMPS , initially at +/- 24V and later also quickly tested till approx +/-29V.
I used -what i thought- was a "genuine(?)" LM1875T.
But to my surprise the board already clipped at about 7V RMS (sinus 1kHz)
Checked the board, but nothing found, all ok.
Output power resistor was 8 Ohm. Up till 7 Volt RMS no strange effects could be noticed, sinus looks clean before clipping.
Offset around 1mV (shorted input) and no visible oscillations on my Rigol scope. Square wave also looked ok. (Only tested however on pure resistive load).
But obviously 7V RMS out is approx 6 W and way out of specification.
Decided to replace the "LM1875t" by the one supplied with the kit (the version with the two side notches, which is also considered fake in earlier posts).
BUT this chip version performed much better, clipping just under 14V RMS, delivering about 24W.
By the way, i could not replicate the "top sinus" oscillations or noise reported by o.a. Chris.
Did not perform the "ultimate" short circuit test and kept the voltage generally under +/-25V for the kit chip.
Nevertheless a quick test: When inserting a square wave and voltages over 25 V - i noticed oscillations, which -however- disappeared at once under 25V.
Distortions under sinus test Fourier/FFT looked ok (before clipping).
Clearly I am having difficulties finding genuine LM1875T's in the Netherlands...
The first defective/fake LM1875t was bought locally, but the original kit-chip is probably also fake but at least produces almost 25W of clean power.
Will continue doing (more precise) measurements and tests in coming few days.
Fred
Today i tested a first Ebay LM1875 kit.
So let me give my first (premature) impressions.
Hooked on the board to my SMPS , initially at +/- 24V and later also quickly tested till approx +/-29V.
I used -what i thought- was a "genuine(?)" LM1875T.
But to my surprise the board already clipped at about 7V RMS (sinus 1kHz)
Checked the board, but nothing found, all ok.
Output power resistor was 8 Ohm. Up till 7 Volt RMS no strange effects could be noticed, sinus looks clean before clipping.
Offset around 1mV (shorted input) and no visible oscillations on my Rigol scope. Square wave also looked ok. (Only tested however on pure resistive load).
But obviously 7V RMS out is approx 6 W and way out of specification.
Decided to replace the "LM1875t" by the one supplied with the kit (the version with the two side notches, which is also considered fake in earlier posts).
BUT this chip version performed much better, clipping just under 14V RMS, delivering about 24W.
By the way, i could not replicate the "top sinus" oscillations or noise reported by o.a. Chris.
Did not perform the "ultimate" short circuit test and kept the voltage generally under +/-25V for the kit chip.
Nevertheless a quick test: When inserting a square wave and voltages over 25 V - i noticed oscillations, which -however- disappeared at once under 25V.
Distortions under sinus test Fourier/FFT looked ok (before clipping).
Clearly I am having difficulties finding genuine LM1875T's in the Netherlands...
The first defective/fake LM1875t was bought locally, but the original kit-chip is probably also fake but at least produces almost 25W of clean power.
Will continue doing (more precise) measurements and tests in coming few days.
Fred
Hi
according to the other "advanced" thread i want to ask here for the mono board if somebody had tried to change just pin1 +2 (inverted and inverting input leads)
the idea is tho solder 2 pin instead of the legs 1+2 and change the legs to the new position
here are the positive feedback of this test: #64 and #66 by FF
https://www.diyaudio.com/forums/chi...ration-composite-amplifier-7.html#post6011535
can we expect some changes in SQ? stability seams much better.
chris
according to the other "advanced" thread i want to ask here for the mono board if somebody had tried to change just pin1 +2 (inverted and inverting input leads)
the idea is tho solder 2 pin instead of the legs 1+2 and change the legs to the new position
here are the positive feedback of this test: #64 and #66 by FF
https://www.diyaudio.com/forums/chi...ration-composite-amplifier-7.html#post6011535
can we expect some changes in SQ? stability seams much better.
chris
...just to give you a hint that maybe you didn´t know. i read this by a very good member (Markw4) in the DAC threads
pcb 30 pcs about 10 euros..nice jumpers included
- the terminals will be not nice i guess
ALLDREI 100Stk leiterplatte Kit - 30 PCB Universal Board + 30 Kopfleiste + 10 Screw Terminal + 30 Jumper Caps: Amazon.de: Gewerbe, Industrie & Wissenschaft
chris
pcb 30 pcs about 10 euros..nice jumpers included
- the terminals will be not nice i guess
ALLDREI 100Stk leiterplatte Kit - 30 PCB Universal Board + 30 Kopfleiste + 10 Screw Terminal + 30 Jumper Caps: Amazon.de: Gewerbe, Industrie & Wissenschaft
chris
not correct formulated: - i would get fast positive feedback of any DC offset + noise !!!
here is an idea to change it to and inverted LM1875 -
Another Inverting LM1875
chris
Tested a prototype dual channel version (with standard components, but input Cap replaced by 2.2uF MKs. The right channel is tested "stable", but the left channel starts to oscillate with a square wave and output at approx 9V RMS and supply voltage at 25V. To stop the oscillations the supply voltage needs to be reduced under 23V.
Non of these effects on the right channel, which also functions fine with 26.5V and then delivers 31W of clean power (8 Ohm) - just before clipping.
Will now built final three boards (one for surround effects) with -hopefully- genuine LM1875's and better capacitors.
However despite the above stability issue the SQ is simply excellent, (but.. my ears are no longer a good reference
Wagner sounds majestically, and that is quite a compliment considering the cost and simplicity..
Clearly my Marantz PM673 amplifier (3x40W) can not compete.
The (fake) LM1875 delivers sufficient power for my living room (approx 50m2).
I also tried the Haffler surround scheme and it functions very well, no stability issues. Will later on use another LM1875 amplifier board -configured as a substraction (left minus right) matrix amplifier to feed my two rear speakers.
However, despite the excellent SQ i am still worried about the stability issues, so work in progress....
Non of these effects on the right channel, which also functions fine with 26.5V and then delivers 31W of clean power (8 Ohm) - just before clipping.
Will now built final three boards (one for surround effects) with -hopefully- genuine LM1875's and better capacitors.
However despite the above stability issue the SQ is simply excellent, (but.. my ears are no longer a good reference
Wagner sounds majestically, and that is quite a compliment considering the cost and simplicity..
Clearly my Marantz PM673 amplifier (3x40W) can not compete.
The (fake) LM1875 delivers sufficient power for my living room (approx 50m2).
I also tried the Haffler surround scheme and it functions very well, no stability issues. Will later on use another LM1875 amplifier board -configured as a substraction (left minus right) matrix amplifier to feed my two rear speakers.
However, despite the excellent SQ i am still worried about the stability issues, so work in progress....
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..price compare to a commercial amp
Hi
compared to the Marantz PM6006 i try to list all components for a complete amp with single chip per channel to have a cost overview between DIY vs. commercial amp.
https://www.diyaudio.com/forums/chip-amps/341675-ebay-mono-lm1875-kit-43.html#post6009010
best parts amp:
https://www.diyaudio.com/forums/chip-amps/341675-ebay-mono-lm1875-kit-37.html#post5997205
cap bank version 2:
https://www.diyaudio.com/forums/chip-amps/341675-ebay-mono-lm1875-kit-39.html#post6002877
I found a lot of components in my work bench but i try to give you the price for each components.
attached the list --> 173 euros for a complete amp
chris
Merry Christmas and a happy new YEAR 2020 !!!
Hi
compared to the Marantz PM6006 i try to list all components for a complete amp with single chip per channel to have a cost overview between DIY vs. commercial amp.
https://www.diyaudio.com/forums/chip-amps/341675-ebay-mono-lm1875-kit-43.html#post6009010
best parts amp:
https://www.diyaudio.com/forums/chip-amps/341675-ebay-mono-lm1875-kit-37.html#post5997205
cap bank version 2:
https://www.diyaudio.com/forums/chip-amps/341675-ebay-mono-lm1875-kit-39.html#post6002877
I found a lot of components in my work bench but i try to give you the price for each components.
attached the list --> 173 euros for a complete amp
chris
Merry Christmas and a happy new YEAR 2020 !!!
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