Just wanna share our experience and wanna know what you think of the result.
During the past two weeks, 8 of music lovers (3 are DIYers, 3 are classic musicians, 1 drumer) got together and did some comparision. Below are equipments we 've used.
Amplifier:
A) classic 25W/ch LM3875
(BG 4.7UF input, FC cap 1000UF, 22.1K/681 RN60D dale res). Fedde's Chillamp alike PCB.
B) 50W /ch LM3875 with snubberized PS (rev 2), same componenys quality as bove.
C) ESP's Project101 30Wrms Mosfet Amp (high power circuit, one 25-0-25/250VA tranf and 40,000UF total)
Speakers:
----------
A). PSB Alpha B
b). DIY's fulll range Fostex 127E with external super tweeters
Setup
--------
- All config based on NAD 521BEE CD player, directly connect to the amp
- Listening room is 4 x 6 m.
- All comment/voting are done via blind tests except the last one (#8)
Results (summary)
-----------------
1. Musicians tend to like the classic 25W GC due to it's close to LIVE music. particularly for the drumer and percussion lovers.
2. Tube lover perfer the sound of classic CG + Fostex 127
3. Most of young pop/rock lover ( <30 year old) perfer Alpha B (either with snubberized CG or ESP101 amp).
4. Difficult to differentiate the Snubberized GC and ESP101 amp in general except with lounder level
5. They can diffirentiate the sound of classic GC and snuberrized one
6. Zen v4 came at the later stage. It sounds much like the Classic CG but slighly more LIVELY
7. Normalized highest scores for amps by type of music:
For vocal music --> Classic CG 25W
For percussion music --> Classic CG 25W
For classic rock/complicated music --> the ESP101 amp
For pop/rock music --> snubberized GC and ESP101 amp
8. Question: If one need to choose one amp back home for their "everyday uses" regardless of speakers, room and type of music. One vote per person:
Rank #1 - ESP101's 30W amp ( 5 out of 8) - "why- as suiatble for most of speakers, ...and most kind of music... most practical for everyday uses"
Rank #2 - Snubberized GC ( 3 out of 8) - "why - I like the bass and its details of mid"
Rank #3 - Classic GC ( 0 out of 8) - "why - Good sounding and close to LIVE MUSIC however it might be for the one who have a special good listening room and good acessaries..... too picky to work with speakers, room and type of music")
And you?
During the past two weeks, 8 of music lovers (3 are DIYers, 3 are classic musicians, 1 drumer) got together and did some comparision. Below are equipments we 've used.
Amplifier:
A) classic 25W/ch LM3875
(BG 4.7UF input, FC cap 1000UF, 22.1K/681 RN60D dale res). Fedde's Chillamp alike PCB.
B) 50W /ch LM3875 with snubberized PS (rev 2), same componenys quality as bove.
C) ESP's Project101 30Wrms Mosfet Amp (high power circuit, one 25-0-25/250VA tranf and 40,000UF total)
Speakers:
----------
A). PSB Alpha B
b). DIY's fulll range Fostex 127E with external super tweeters
Setup
--------
- All config based on NAD 521BEE CD player, directly connect to the amp
- Listening room is 4 x 6 m.
- All comment/voting are done via blind tests except the last one (#8)
Results (summary)
-----------------
1. Musicians tend to like the classic 25W GC due to it's close to LIVE music. particularly for the drumer and percussion lovers.
2. Tube lover perfer the sound of classic CG + Fostex 127
3. Most of young pop/rock lover ( <30 year old) perfer Alpha B (either with snubberized CG or ESP101 amp).
4. Difficult to differentiate the Snubberized GC and ESP101 amp in general except with lounder level
5. They can diffirentiate the sound of classic GC and snuberrized one
6. Zen v4 came at the later stage. It sounds much like the Classic CG but slighly more LIVELY
7. Normalized highest scores for amps by type of music:
For vocal music --> Classic CG 25W
For percussion music --> Classic CG 25W
For classic rock/complicated music --> the ESP101 amp
For pop/rock music --> snubberized GC and ESP101 amp
8. Question: If one need to choose one amp back home for their "everyday uses" regardless of speakers, room and type of music. One vote per person:
Rank #1 - ESP101's 30W amp ( 5 out of 8) - "why- as suiatble for most of speakers, ...and most kind of music... most practical for everyday uses"
Rank #2 - Snubberized GC ( 3 out of 8) - "why - I like the bass and its details of mid"
Rank #3 - Classic GC ( 0 out of 8) - "why - Good sounding and close to LIVE MUSIC however it might be for the one who have a special good listening room and good acessaries..... too picky to work with speakers, room and type of music")
And you?
I've built both the classic LM3875 amp (based on BrianGTs premium kit) and the ESP101. I would have to say that I enjoy the ESP101 more than the LM3875, although I am running my ESP (link) a bit higher than yours. I think the mids and highs are more defined on the ESP101 and the bass is quite tight. Both are good amps, but I would give the edge to the ESP101 for sure.
loong said:Just wanna share our experience and wanna know what you think of the result.
During the past two weeks, 8 of music lovers (3 are DIYers, 3 are classic musicians, 1 drumer) got together and did some comparision. Below are equipments we 've used.
Amplifier:
A) classic 25W/ch LM3875
(BG 4.7UF input, FC cap 1000UF, 22.1K/681 RN60D dale res). Fedde's Chillamp alike PCB.
B) 50W /ch LM3875 with snubberized PS (rev 2), same componenys quality as bove.
C) ESP's Project101 30Wrms Mosfet Amp (high power circuit, one 25-0-25/250VA tranf and 40,000UF total)
Speakers:
----------
A). PSB Alpha B
b). DIY's fulll range Fostex 127E with external super tweeters
Setup
--------
- All config based on NAD 521BEE CD player, directly connect to the amp
- Listening room is 4 x 6 m.
- All comment/voting are done via blind tests except the last one (#8)
Results (summary)
-----------------
1. Musicians tend to like the classic 25W GC due to it's close to LIVE music. particularly for the drumer and percussion lovers.
2. Tube lover perfer the sound of classic CG + Fostex 127
3. Most of young pop/rock lover ( <30 year old) perfer Alpha B (either with snubberized CG or ESP101 amp).
4. Difficult to differentiate the Snubberized GC and ESP101 amp in general except with lounder level
5. They can diffirentiate the sound of classic GC and snuberrized one
6. Zen v4 came at the later stage. It sounds much like the Classic CG but slighly more LIVELY
7. Normalized highest scores for amps by type of music:
For vocal music --> Classic CG 25W
For percussion music --> Classic CG 25W
For classic rock/complicated music --> the ESP101 amp
For pop/rock music --> snubberized GC and ESP101 amp
8. Question: If one need to choose one amp back home for their "everyday uses" regardless of speakers, room and type of music. One vote per person:
Rank #1 - ESP101's 30W amp ( 5 out of 8) - "why- as suiatble for most of speakers, ...and most kind of music... most practical for everyday uses"
Rank #2 - Snubberized GC ( 3 out of 8) - "why - I like the bass and its details of mid"
Rank #3 - Classic GC ( 0 out of 8) - "why - Good sounding and close to LIVE MUSIC however it might be for the one who have a special good listening room and good acessaries..... too picky to work with speakers, room and type of music")
And you?
What was the rail capacitance per channel of the snubberized GC?
Thanks
Greg
Those results correspond with mine.
The snubberised PSU enables the GC to keep control with difficult/more demanding passages of music such as rock. For overall listening, I am using the snubberised LM3886.
But the 'classical' 1000 uF/rail LM3875 (inverted in my case) has a bit more 'magic' and comes out better with acoustic type music. That 'magic' is lost in the snubberised version (I have tried both LM3875 and LM3886 snubberised).
All versions that I am talking about above were auditioned buffered.
The snubberised PSU enables the GC to keep control with difficult/more demanding passages of music such as rock. For overall listening, I am using the snubberised LM3886.
But the 'classical' 1000 uF/rail LM3875 (inverted in my case) has a bit more 'magic' and comes out better with acoustic type music. That 'magic' is lost in the snubberised version (I have tried both LM3875 and LM3886 snubberised).
All versions that I am talking about above were auditioned buffered.
Nuuk said:
Nuuk - I've learnt lots of things from your informative site. Thanks.
Some of us joke that they might plan to have a couple of amp when listening to different type of music. Snubberized 50W GC for everyday uses (mostly pop/rock music). While the classical 25W GC is for more seriously listening of vocal/acoustic or even light classical music. Nothing is ideal and suit for all.
BTW, if I have to pick ONE and the only one for my "living" room, I would go for Fedde's Chillamp-alike 25W classic GC (22K/680 all carbon film res) as it's LIVELY like the music is being played there!
I don't cares what hi-fi/good measured spec is as long as I enjoy its sound of music.
Nuuk - I've learnt lots of things from your informative site. Thanks.
And khapkoon to you for the wonderful time that I have spent in your lovely country. I'm glad that I could give something back.
I very nearly said the same thing! In fact, as the GC circuits are relatively compact, it wouldn't be too difficult to house two in the same case! But I'm not sure if there is a convenient way to switch speakers between them.
During new year holidays, many of my friends's friends had done some experiment over the DIY amp, seriously. Half of them are working as prefessional reviewwe for local audio magazines. The following amp had been tested:
1). LM3875 Premium kit (running with 22-0-22V)
2). LM3875 Premium kit with snubberized PS
3). Fedde's chillamp's alike (25W, carbon film, 4.7UF BG cap at input, single trans and normal bridge)
4). Halfer DH220 clone (rebuilt with newer MOSFETs from Hitachi) with the same passive pre
5). ESP's Project 101 with the same passive pre
Same speaker & cables, same room. Weighted type of music: pop/rock(weight 40%), acoustic (weight 30%), vocal(10%), classic vocal(10%) -- weight by frequncy of listening.
I was told that we had enjoyed playing with these toys very much. One question was asked "if you can write down whatever you want for your readers, or prefer to have it setup in their living room without worrying about reviewing it. ")
And the result of majority votes, surprisingly: The most desirable (may be different from "best) result came from the 25W CHILLAMP-alike GC with a DIY active subwoffer
why ? It's said that due to the 'magic' of classic GC while better & more control bass.
Getting back to basis.
Probably, the saying
"only the simplest can accommodate the most complex"
is still & always true.
PS: Loong, I just relocated back to BKK as well. Please check yr email in case we can meet up here.
1). LM3875 Premium kit (running with 22-0-22V)
2). LM3875 Premium kit with snubberized PS
3). Fedde's chillamp's alike (25W, carbon film, 4.7UF BG cap at input, single trans and normal bridge)
4). Halfer DH220 clone (rebuilt with newer MOSFETs from Hitachi) with the same passive pre
5). ESP's Project 101 with the same passive pre
Same speaker & cables, same room. Weighted type of music: pop/rock(weight 40%), acoustic (weight 30%), vocal(10%), classic vocal(10%) -- weight by frequncy of listening.
I was told that we had enjoyed playing with these toys very much. One question was asked "if you can write down whatever you want for your readers, or prefer to have it setup in their living room without worrying about reviewing it. ")
And the result of majority votes, surprisingly: The most desirable (may be different from "best) result came from the 25W CHILLAMP-alike GC with a DIY active subwoffer
why ? It's said that due to the 'magic' of classic GC while better & more control bass.
Getting back to basis.
Probably, the saying
"only the simplest can accommodate the most complex"
is still & always true.
PS: Loong, I just relocated back to BKK as well. Please check yr email in case we can meet up here.
carlosfm said:
Regulated snubberized PSU blows away everything.
Carlos, All,
Sorry if this may upset you.
Two of my friends had chance to playaround with the orginal 47Lab's Gaincard in New York for months. After trying many version of kits here ( inc. 3875 Premium kit w/ and w/o regulated PS, Carlos's snubberized PS), they recently agreed that a CLASSIC LM3875 25W GC [actually, Chillamp's clone with all carbon res but one single PS+trans. No snubberized or regulated PS al all] sounds very very close to the orginal Gaincard.
Cheers,
nina said:
Is that good?
Do you have speakers and cables to match such a picky amp?
I've bee there, done that, and presently I can say I'm much more satisfied with the performance of the amp than the first ones I made with low capacitance.
It simply couldn't drive 99% of the speakers I tested it with.
From horrible sounding to quite good, it was just a question of changing cables or speakers.
If you can live with good mids and treble but flappy, untight bass in such a way that you end yourself picking the right music for the amp...
Nuuk said:Well without knowing the correct snubber values for the regulated PSU, we will just have to take your word for that!
Get your LM338 PSU out of your basement, turn on the soldering iron and full speed ahead.
http://www.diyaudio.com/forums/showthread.php?s=&threadid=56106
carlosfm said:
Get your LM338 PSU out of your basement, turn on the soldering iron and full speed ahead.
http://www.diyaudio.com/forums/showthread.php?s=&threadid=56106
Thanks carlos. I never read that thread before. It looks interesting. BTW, just a couple questions:
1). Can the T1 and T2 trans be physically separate trans?
2). Just wonder if the current from single LM338 is adequate for 56W version of LM3875?
3) Have you ever compared it with the battery PS?I guess they sound close, right?) ?
Thanks,
nina said:
Shoot.
nina said:
Yes, of course.
That's even better.
nina said:
You can feed two chips with no problems.
The LM338 has a peak current of 12A, at a voltage differential between input-output of around 10V (what I recommend).
Anyway, the results speak for theirseves, my speakers are difficult and I'm using this PSU for a stereo amp (2xLM3886).
I have never had such a tight, clean sound, top to bottom.
nina said:
No.
I have 4 SLA 12V/7A batteries and no time to test them yet.
They may need a snubber too.
What do you guys mean when an amp can't drive speakers. I'm using a simple 3875 IGC with 12 guage 10' homedepot cable driving 4 ohm GR research AV2s. No problems at all. I also have driven some adire HE10.1s without any problems. No buzzes, hisses or anything, but the heatsinks do get warm from time to time.
Do I have to push the amp really hard to see if it can't drive speakers?
Thanks
Alex Kunec
Do I have to push the amp really hard to see if it can't drive speakers?
Thanks
Alex Kunec
akunec said:
It has nothing to do with noise.
You will one day find out, when you listen to a really TIGH bass, fast, clean sound, top to bottom.
When the amp is not properly driving the speakers it will show up as untight bass, even at low volumes.
The problem may be subtle and not so easy to detect, or it can be very obvious.
A 4 ohm rated speaker doesn't mean by itself that it's hard to drive.
There are 8 ohm speakers that have impedance dips (mainly in the bass) to well below 4 ohms. And these need a good amp.
You may not notice anything wrong if you listen to some types of music, or if your speakers are easy to drive.
But to test an amp, I always use music with strong bass, like Ben Harper, Counting Crows (first album), etc.
With these CDs I use for a real test, sometimes I put some expensive systems sounding like junk.
And then they say it's the room...
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