2007年6月25日 · Hi all, I would like to build the phono preamp from the LT1115 datasheet, the schematic shown on the first page of the document. This will be used with a Dynavector 20X-L (.3 mv - moving coil cartridge). I have a few questions about the circuit: The 2N4304 FET used to bias the LT1115 output...

2007年6月25日 · I finally finished building and testing the LT1115 preamp. Indeed a pleasant surprise! "No" noise, no hum, sounds nice with my old Rega and Ortofon MC30. Now this ugly duckling PCB will live in a suitable case, formerly occupied by a Hiraga MC preamp. Finished board: View attachment 1374037 Testing: View attachment 1374038 RIP - soon:

2004年7月12日 · none of the previosly mentioned op amps are low noise - when used with a typical mm catridge input Z the low voltage noise in LT1028/1128/1115, AD797, LM4562 is acheived by heavy bias of the input Qs which gives large base current noise and input current noise is multiplied by the source Z to give output noise

Also the LT1115 chip is a fair bit noiser for a MM cartridge than an NE5534A as its current noise is dissappointing (not unusual for a chip with ultra-low voltage noise). This circuit is best matched for MC inputs where the source impedance is low.

2013年4月20日 · There are many potential candidates, but the LT1115 form Linear technology is a good place to start. Changing op-amps has the potential to make these types of circuits unstable, depending on the high-frequency phase characteristics of the device, but with the LT1115 the only change that I think is necessary is to add a 100R resistors in series ...

2019年1月25日 · About that, what I have just noticed is that the THD results with the LT1115 and the LT1028 are exactly the same. I guess one of the models is wrong. Those are the files that come with LTSpice, so they should be right. And they are only filed, apparently, in the asy directory, which is wrong.

2025年1月14日 · Working on a tape head preamp for open reel with selectable EQ for NAB and CCIR curves. This is based on the reference application on the LT1115 datasheet and Rod Elliott's Project 247. This is really a stab in the dark so feedback would be greatly appreciated.

2020年7月22日 · lt1115 is not very good for moving magnet carts due to its aw impedance although it can take higher max Vcc.lm833 is actually a very good op-amp for mm phono.The problem you have is that the 17.5v regulators are almost at the limit of max VCC of both lm833 and opa627...I'd suggest the usual ne5532 instead, or better m5220 if you can find some in a damaged casette player, but i've seen njm4580 ...

Guys, you are re-inventing wheel with the LT1115. It is a BJT, very low voltage noise, very low distortion OA, especially suitable for MC cartridge. It is very similar to LT1028, regarding noise and distortion. The 1st google click leads to Linear Technology website and datasheet. It has been in production about 10 years, AFAIK.

2023年10月22日 · Lt1115 datasheet shows that 2mA current source loading the output for more circuits , not just phono circuits.I always felt it is just a trend to add current sources to load operational amplifiers, not sure who started this, probably Nelson Pass, but they should get warmer thus noisier and thermal noise is not smth you want for phono preamplifiers so I'd say it is a bad ideea to add 2mA ...