I will try to answer this wrt this preamp. This has minimum gain 1.XX and with both feedback kept at 10K it is 2. which is not big and distortion is lowest. Almost equal to OPAMP chip specs. With no gain it turns out to add distortion for audio. Nobody want buffer with gain. Hence here it is kept with lowest possible gain.
DIY Super Simple Preamp
- Thread starter sachu888
- Start date
I will try to answer this wrt this preamp. This has minimum gain 1.XX and with both feedback kept at 10K it is 2. which is not big and distortion is lowest. Almost equal to OPAMP chip specs. With no gain it turns out to add distortion for audio. Nobody want buffer with gain. Hence here it is kept with lowest possible gain.
Are you sure the pre is better than Marantz/CA..?
real shocking , it is just an op-amp stage!!
i will be testing it, powered version i have some opamp etc in spare boxes .
@om battery power is also little noisy not pure DC due to type of reaction ..
but will be better than low cost PSUs.
can some one can make a slim dual supply from cell phonecharger...
I did not find any source to get SMPS working nice for preamp (in fact dual Supply for OPAMP). So with use of r-core I designed a linear PS with very highly filtered lines. Chemical noises does not affect audio unless you are in RF band. Battery is preferred and easy source for low current application like this.
What Sachin is referring - this is low cost buffer with minimum components/gain. With good OPAMPs this could be used to construct nicer preamps. Like one we used Pass B1, I have experimented with two SSPs - one at input and another at output. Between both you have volume control. This make Volume control invisible to source as well as power amp.
Again w/o using 2 SSP, single SSP with >=25K? log pot makes nicer preamp. Murali is using same configuration. Ask him further.
Again guys its your choice, I am not marketing anything. Just read this as technical explanation.
What Sachin is referring - this is low cost buffer with minimum components/gain. With good OPAMPs this could be used to construct nicer preamps. Like one we used Pass B1, I have experimented with two SSPs - one at input and another at output. Between both you have volume control. This make Volume control invisible to source as well as power amp.
Again w/o using 2 SSP, single SSP with >=25K? log pot makes nicer preamp. Murali is using same configuration. Ask him further.
Again guys its your choice, I am not marketing anything. Just read this as technical explanation.
Last edited:
iaudio
Well-Known Member
Got my kit, thank you. 
sachu888
Well-Known Member
Got my kit, thank you.
Great,now build it tonight and tell us how does it sound
Regards,
Sachin
iaudio
Well-Known Member
Sachin, You dont know me well enough! I am a master procrastinator and DIY handicapped!
Just spoke to bibin3210, telling him I would be bugging him as and when I need help with the SSP build
Just spoke to bibin3210, telling him I would be bugging him as and when I need help with the SSP build
sachu888
Well-Known Member
Sachin, You dont know me well enough! I am a master procrastinator and DIY handicapped!
Just spoke to bibin3210, telling him I would be bugging him as and when I need help with the SSP build
Now I know you
All the best for your first DIY
.This should be fun.Regards,
Sachin
Hi All,
Yesterday one of our forum member Shanpson from chennai dropped in to audition my SSP Preamp with Emotiva power amp. He had earlier heard my Marantz PM6003 and always felt and expressed that his Norge Concerto Gold (125 w rms/ch) was not sounding like that. I asked him to wait for my tube pre build(under progress) to be over so that he can take an audition and decide if he can add the same in his chain. I had told him that a seperate pre-amp would always make a difference in his chain.
His system consists of Cambridge Audio DV-99>Norge Concert Gold>Mordaunt Short Aviano-2 BS Speakers. So I asked him to bring his Norge amp and DV-99 DVD Player(as he felt some doubt about SQ of the source). I had only recommended this source to him a couple of years back.
First I played his CA DV-99 DVD Player + SSP Pre with my Emotiva mini-X-a-100 power amp (50w rms/ch @ 8 ohms) with MS Aviano speakers, the sound was very detailed with good bass and highs. My SSP Pre was built using 2x49990 opamp mounted on a SOIC to 8 Pin DIP adapter.
Next we connected the Norge Concert Gold amp as repalcement to the pre + power amp, retaining the rest of the chain. Now the bass had considerably reduced, sound stage was small, mids were rough and highs not well extended. Overall the sound was less engaging.
Immediately shanpson asked me to connect the SSP Pre instead of the Norge Pre-amp ckt so that we can audition the amp. Earlier when I had the Norge 2060 int amp with me I had tweaked the pre amp with some better spec opamps and this gave me the courage to meddle with the Norge concert gold amp. So with the permission and the encouragement, went ahead to remove the cover of the amp. The pre-amp inside it was the same as the Norge 2060 (using TL072 opamps) and I could locate the input wires of the power amp , which were actually 2 mono amps. The pre amp is powered by a -15-0-+15 V power supply which is tapped from Toroid transformer having 2 secondaries (one each for the power and the pre). Now I disconnected the power amp's signal input and connected it to a wires terminated with 2xRCAs at one end. I connected the RCA plugs to the SSP pre's output, and the SSP pre was fed from the CA DV-99 output. Now we played the same track ( a tamil film song).
What happened after that was that the FM was in disbelief, his jaw dropped , he was speech less, he could not believe that his Norge amp was playing. Now the soundstage was improved, details increased, vocals were mellowed, not the harsh as earlier, and the bass was increased and very tight. We ran a couple of tracks and for my ears, the 49990 sounded a bit bright and forward, since there was a slight emphasis in the high frequencies( I suspect could be due to the Norge power amp) which made the voices sound a bit shrill, and definitely create ear-fatigue for the listener. So I told him that we can try with 2134 opamp. So we switched off the entire thing and I replaced the opamp of the SSP Pre with 2134 opamp. Now we again played the same numbers and I one was in for a surprise that this 2134 opamp used to sound a bit laid back in my set-up now sounded a bit nuetral, in the Norge set-up. Now the bright sound was gone, but the details were intact and the bass was still improved. The FM liked this sound very much and immediately wanted me to implement this change in his amp. Immediately I called Mr.Sachin at Nashik, and as usual he was prompt to respond to my request for a SSP PCB with 2134 opamp and other components. The board has since been dispatched by him, today and hope to receive it tomorrow after which I will install the same in the Norge amp.
So, my suggestion to all Norge amp owners, is try this SSP pre in place of the stock pre in your system, it definitely makes a very significant sound improvement. Also pl post your feed back in this forum for all others members to benefit.
Just thought I will post my experience.
N.Murali
Yesterday one of our forum member Shanpson from chennai dropped in to audition my SSP Preamp with Emotiva power amp. He had earlier heard my Marantz PM6003 and always felt and expressed that his Norge Concerto Gold (125 w rms/ch) was not sounding like that. I asked him to wait for my tube pre build(under progress) to be over so that he can take an audition and decide if he can add the same in his chain. I had told him that a seperate pre-amp would always make a difference in his chain.
His system consists of Cambridge Audio DV-99>Norge Concert Gold>Mordaunt Short Aviano-2 BS Speakers. So I asked him to bring his Norge amp and DV-99 DVD Player(as he felt some doubt about SQ of the source). I had only recommended this source to him a couple of years back.
First I played his CA DV-99 DVD Player + SSP Pre with my Emotiva mini-X-a-100 power amp (50w rms/ch @ 8 ohms) with MS Aviano speakers, the sound was very detailed with good bass and highs. My SSP Pre was built using 2x49990 opamp mounted on a SOIC to 8 Pin DIP adapter.
Next we connected the Norge Concert Gold amp as repalcement to the pre + power amp, retaining the rest of the chain. Now the bass had considerably reduced, sound stage was small, mids were rough and highs not well extended. Overall the sound was less engaging.
Immediately shanpson asked me to connect the SSP Pre instead of the Norge Pre-amp ckt so that we can audition the amp. Earlier when I had the Norge 2060 int amp with me I had tweaked the pre amp with some better spec opamps and this gave me the courage to meddle with the Norge concert gold amp. So with the permission and the encouragement, went ahead to remove the cover of the amp. The pre-amp inside it was the same as the Norge 2060 (using TL072 opamps) and I could locate the input wires of the power amp , which were actually 2 mono amps. The pre amp is powered by a -15-0-+15 V power supply which is tapped from Toroid transformer having 2 secondaries (one each for the power and the pre). Now I disconnected the power amp's signal input and connected it to a wires terminated with 2xRCAs at one end. I connected the RCA plugs to the SSP pre's output, and the SSP pre was fed from the CA DV-99 output. Now we played the same track ( a tamil film song).
What happened after that was that the FM was in disbelief, his jaw dropped , he was speech less, he could not believe that his Norge amp was playing. Now the soundstage was improved, details increased, vocals were mellowed, not the harsh as earlier, and the bass was increased and very tight. We ran a couple of tracks and for my ears, the 49990 sounded a bit bright and forward, since there was a slight emphasis in the high frequencies( I suspect could be due to the Norge power amp) which made the voices sound a bit shrill, and definitely create ear-fatigue for the listener. So I told him that we can try with 2134 opamp. So we switched off the entire thing and I replaced the opamp of the SSP Pre with 2134 opamp. Now we again played the same numbers and I one was in for a surprise that this 2134 opamp used to sound a bit laid back in my set-up now sounded a bit nuetral, in the Norge set-up. Now the bright sound was gone, but the details were intact and the bass was still improved. The FM liked this sound very much and immediately wanted me to implement this change in his amp. Immediately I called Mr.Sachin at Nashik, and as usual he was prompt to respond to my request for a SSP PCB with 2134 opamp and other components. The board has since been dispatched by him, today and hope to receive it tomorrow after which I will install the same in the Norge amp.
So, my suggestion to all Norge amp owners, is try this SSP pre in place of the stock pre in your system, it definitely makes a very significant sound improvement. Also pl post your feed back in this forum for all others members to benefit.
Just thought I will post my experience.
N.Murali
Last edited:
sachu888
Well-Known Member
Thank you Sir,
very nice and detailed review.It will certainly helpful for FMs.Too bad I don't have components to complete my build
Regards,
Sachin
very nice and detailed review.It will certainly helpful for FMs.Too bad I don't have components to complete my build
Regards,
Sachin
Hi sachin,
This is very short and small story (ofcourse with facts), I have a bigger one lined up for the CNC Phono, but waiting for my experiments to be over so that I can come to a conclusion and hope my findings to be of some use to potential DIYers who want to build one.
N.Murali
This is very short and small story (ofcourse with facts), I have a bigger one lined up for the CNC Phono, but waiting for my experiments to be over so that I can come to a conclusion and hope my findings to be of some use to potential DIYers who want to build one.
N.Murali
Jith77
Active Member
thank you for the kit. will try and put it together in month end. meanwhile will watch this thread closely
Audiodoc
Well-Known Member
Even I have tried four preamplifiers with my Norge 1000.
1. Default Norge Preamplifier. Opamp swapping TL072, NE5532, burr brown2134, OPA627 on adapters.
2. DIY opa627 dual fixed gain preamplifier.
3. Pass B1
4. Pass BOZ
1 & 2 are integrated into the Norge 1000 cabinet and can be switched with a toggle switch.
1. Default Norge Preamplifier. Opamp swapping TL072, NE5532, burr brown2134, OPA627 on adapters.
2. DIY opa627 dual fixed gain preamplifier.
3. Pass B1
4. Pass BOZ
1 & 2 are integrated into the Norge 1000 cabinet and can be switched with a toggle switch.
keith_correa
Well-Known Member
And, which combo sounded the best?
Audiodoc
Well-Known Member
Each had its own benefits but I prefer the B1 for being the most neutral. All the others add something to the signal. Some may like the same (describing the resulting sound as exciting and musical) however the simple B1 unity gain pre is the best.
sachu888
Well-Known Member
If you change the 8.2k resistors to 10k it would have zero gain or unity gain,but I think little gain is always better.
Regards,
Sachin
sachu888
Well-Known Member
Hi,
If anyone do not want to use volume control with this pre then you should do the following as suggested by Omishra in Audiokarma "in each channel, add 1M?,0.25W resistance between 'CW' & 'CCW' pads and piece of wire jumper from 'CW' to 'W'. This is equivalent to connecting input directly at 'W' pads and shunting 1M?, 0.25W from 'W' pad to ground". Else you could have DC offset,which could destroy your amp.
If you want to measure DC offset, set your DMM to at least 200mv's. Put the positive lead on the right or left positive output of the preamp and the negative lead to the negative output. It should read zero
Regards,
Sachin
If anyone do not want to use volume control with this pre then you should do the following as suggested by Omishra in Audiokarma "in each channel, add 1M?,0.25W resistance between 'CW' & 'CCW' pads and piece of wire jumper from 'CW' to 'W'. This is equivalent to connecting input directly at 'W' pads and shunting 1M?, 0.25W from 'W' pad to ground". Else you could have DC offset,which could destroy your amp.
If you want to measure DC offset, set your DMM to at least 200mv's. Put the positive lead on the right or left positive output of the preamp and the negative lead to the negative output. It should read zero
Regards,
Sachin
Audiodoc
Well-Known Member
I agree with Sachin. With most of the amp having high gains a preamplifier with high gain is counterproductive because with gain comes noise. So if you increase the gain at preamplifier stage then you will have to tone down the power amplifier volume knob to prevent clipping. Thus by increasing gain at preamp stage you are boosting the signal as well as noise. If you have a unity gain the SNR will be better.
sachu888
Well-Known Member
Hi all,
please find another pic for battery connection.Some members are first time builders and finding it little difficult,so I thought I should post another detailed pic.
By [URL=http://profile.imageshack.us/user/sachu888]sachu888 at 2012-08-04[/URL]
Regards,
Sachin
please find another pic for battery connection.Some members are first time builders and finding it little difficult,so I thought I should post another detailed pic.
By [URL=http://profile.imageshack.us/user/sachu888]sachu888 at 2012-08-04[/URL]Regards,
Sachin
apk
Well-Known Member
Hi Everyone,
I started and finished building this kit today. I am an absolute newbee to DIY, and had never held a soldering iron before. So I guess getting this done in a day is pretty good (by my standards)
I would'nt have been able to complete this without tons of help from Sachin and Om. A big thank you to both of you :clapping:
So for all the folks who have been procastinating making this kit, go ahead and start it. Before soon, you will be so much into it that you would not want to stop!!
Giving the SSP some time to burn in. First impressions are ok.....a bit lean and harsh on the highs. Should smoothen out with more burn in. But then I am biased....I already have a decent pre-amplifier in my system and I am comparing to that. For the money spent, definitely good sound.
Will post more impressions after a few days of burn in (or till my ears get accoustomed to the new sound !!)
Regards,
APK
I started and finished building this kit today. I am an absolute newbee to DIY, and had never held a soldering iron before. So I guess getting this done in a day is pretty good (by my standards
)I would'nt have been able to complete this without tons of help from Sachin and Om. A big thank you to both of you :clapping:
So for all the folks who have been procastinating making this kit, go ahead and start it. Before soon, you will be so much into it that you would not want to stop!!
Giving the SSP some time to burn in. First impressions are ok.....a bit lean and harsh on the highs. Should smoothen out with more burn in. But then I am biased....I already have a decent pre-amplifier in my system and I am comparing to that. For the money spent, definitely good sound.
Will post more impressions after a few days of burn in (or till my ears get accoustomed to the new sound !!)
Regards,
APK
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