Kappaholic
Active Member
Thanks Renron & omishra for the links!
DIY Simple Active Preamp
- Thread starter HypnoToad
- Start date
murali_n
New Member
Hi Ron,
I don't get you.
I am playing the CNC Phono with the AD823 as the first and 2134 as the second opamp, and 2134 in the SSP. It sounds good.
Have requested sachin for 49990, for an opamp roll. Lets see how it sounds.
N.Murali
murali_n
New Member
Hi Ron,
Now I get you, yes certainly it does not colour the sound.
All it takes is about 10-15 hours for the circuit to burn-in to sound its best. The CNC certainly sounds better than the inbuilt Phono stages of most of the contemporary Integrated amps and beats even certain Phono stages sold seperately. It is a very good value for its money. :thmbsp:
As I posted earlier I am anxious to hear it equipped with 49990, whose technical data claims very low distortion. So it is really tempting to try one. I look forward to Mr.Sachin's feedback after he tries the same in his circuit, after which I will take a call.
N.Murali
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Kappaholic
Active Member
The LME49990 would perform best when mounted in pair on both opamp sockets. During my testing, mix matching opamp combo yielded less desirable performance compared to the paired performance of the better opamp. YMMV, of course.
Recently, I acquired 4 X 49990 and few sockets for 2X49990. For replacement of each AD823 costing twice of AD823 as (2 X 49990 + 1 SOIC-DIP PCB adapter) required for that. For new DIY enthusiast soldering those two 49990 (comes only in SMD package) on both sides of tiny PCB without making damage may turn into PITA. Patience is required.
Kappaholic
Active Member
I would recommend getting three dual SOIC-DIP sets of LME49990, two for CNC & the third one for SSP to get most out of the opamp(requires 6 smd). Mixing LME49990 with other opamps will lose the benefit. Other opamps will sort of contaminate LME49990's performance.
murali_n
New Member
Hi ALL,
I received the 49990 ICs from Mr.Sachin(forwarded by Omishra- a neat job done by you sir)) and been running it on my Phono stage with 2134 and it certainly sounded very detailed and am waiting for it to mellow down, meanwhile ordered one OPA1612 (Dual op amp) SOIC with adapter from element 14 for use in my SS Preamp circuit(since it matches on par with 49990 in specs and has the Burrbrown signature). Will post impressions once I receive the same, and successfully solder it on the adapter :thmbsp:
N.Murali
I received the 49990 ICs from Mr.Sachin(forwarded by Omishra- a neat job done by you sir)) and been running it on my Phono stage with 2134 and it certainly sounded very detailed and am waiting for it to mellow down, meanwhile ordered one OPA1612 (Dual op amp) SOIC with adapter from element 14 for use in my SS Preamp circuit(since it matches on par with 49990 in specs and has the Burrbrown signature). Will post impressions once I receive the same, and successfully solder it on the adapter :thmbsp:
N.Murali
Kappaholic
Active Member
Actually, another set of 49990 will probably smooth things out further than pairing with other opamps. The LME49990 is well balanced with lots of details. I would think using LME49990 only in the opamp chains will retain the balance when processed through SSP with LME49990 (I need to test it when I get the board). From my experience, LME49990 + OPA2134 will lose lower bass extension and speed, compared with using two/paired LME49990 for CNC and this makes the combo sound little more edgy. The 2134 sounds very soothing for low energy music, but when it comes to passages with lots of energy and excitement, it sounds dull and boring, on my set up. (The OPA2134 sounds good, but I almost fell asleep during an audition)
BTW, I think it took about 30 to 50 hours to really make the LME49990 shine. Slight sign of edginess at the high frequency does calm down and it will sound butter smooth and detailed after the initial burn in.
Either way, let us know how OPA1612 fits into the chain. I am some what interested in testing out OPA627's, but it will cost $40+ per socket to play. Based on the review of Fasterdamit, it may not be worth $40 to try.
murali_n
New Member
Hi kappaholic,
My preference would be to use all 49990s for the CNC Phono and the 1612 in the SSP Pre the reason being, to match same ICs for the CNC and 1612s BB signature to tame the brightness of my Marantz CDP 5003 as I am using the SSP Pre for my CDP also. As I have already run about a 3-4 hrs with the 49990s they are losing their bright nature and hope that they will be tamed sooner or later, nevertheless to say that their imaging and details are very exceptional. :thmbsp:
N.Murali
My preference would be to use all 49990s for the CNC Phono and the 1612 in the SSP Pre the reason being, to match same ICs for the CNC and 1612s BB signature to tame the brightness of my Marantz CDP 5003 as I am using the SSP Pre for my CDP also. As I have already run about a 3-4 hrs with the 49990s they are losing their bright nature and hope that they will be tamed sooner or later, nevertheless to say that their imaging and details are very exceptional. :thmbsp:
N.Murali
Kappaholic
Active Member
I became a big fan of LME49990's ever since the CNC build. I've been using LME49990's for both CNC & HTMCPS and I've been a very happy with the performance. It truly reveals the importance of the phono stage for record playback. My main system is driven with HK signature 1.5 amp, which is very neutral & analytical, driving infinity kappa 8.1's speakers and I can confidently say that my vinyl system can knock the socks off the Denon DV-5900 SACD player during playback of Norah Jones "come away with me" SACD album.
I will build the SSP equipped with LME49990 and hoping they play well together. I have few OPA2134 & LME49720's in the opamp stash, just in case.
I will build the SSP equipped with LME49990 and hoping they play well together. I have few OPA2134 & LME49720's in the opamp stash, just in case.
murali_n
New Member
Another advantage of 1612 is that it is dual opamp and just needs only one adapter/side to solder to fix it on a DIP track. If it sounds good and on par with 49990, perhaps we may suggest sachin/ omishra to make PCB with SOIC track so that the adapter can be eliminated.
Just my 2 cents.
N.Murali
Just my 2 cents.
N.Murali
Small bump, I have a particular question, after reading the entire thread:
I need a small amp for my mp3 player (Zune HD). The headphone out simply isn't loud enough.
What would you guys suggest for a configuration?
Some side notes:
-I'd like to have 3.5mm stereo jack in, and either 3.5mm or RCA out (using CD input or similar on the receiver)
-I plan on running this with a Yamaha RX-V692 and JBL 4410's. I'd be fine with some extra bass.
-I don't care much about a volume adjustment, should I just add a resistor in place of the pot(s)? If so, what value?
I need a small amp for my mp3 player (Zune HD). The headphone out simply isn't loud enough.
What would you guys suggest for a configuration?
Some side notes:
-I'd like to have 3.5mm stereo jack in, and either 3.5mm or RCA out (using CD input or similar on the receiver)
-I plan on running this with a Yamaha RX-V692 and JBL 4410's. I'd be fine with some extra bass.
-I don't care much about a volume adjustment, should I just add a resistor in place of the pot(s)? If so, what value?
I think you should consider below 2 changes. HypnoToad, please correct me.
- Exchange positions of resistances 8.2KΩ and 10KΩ by each other. This will add more gain.
- If you don't want to install volume control then in each channel, add 1MΩ,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 1MΩ, 0.25W from 'W' pad to ground.
Thanks!
I'm going to prototype this tonight, and hopefully I'll be able to hear how it sounds.
My local electronics supply store has hundreds of feet of shelves full of any component you can imagine. Unfortunately, they did not have an AD823. Instead, I got TL072 and TL082 (I think that's what I got).
I will be sure to post my feedback once I get it up and running!
sachu888
Spare the tigers, kill me
You can try OPA2134,they sound better,but LME49990 are best in my system.
Regards,
Sachin