LM1875 still relevant ?

The only genuine one's you will be sure of is to buy from Mouser or digikey and they will cost a lot with shipping. Genuine one's will be available at Lamington Road but moq is 100. :p
Try rs components too. They stock a lot of stuff in india.
 
I'm planning to make my own LM1875 PCB. bought ICs from lamington in 2014, at various rates Rs 50-60-75/- each from multiple shops, Probably all were fakes . One IC (Rs50 from RK) had HF oscillations, Tweeter used to make distorted clipping sound. replaced it with Ic brought from another shop, it worked well. I had used veroboard. Sound was very good (for supposedly fakes) at +/-12V @6W P. Ch. 4Ohm speaker when compared to Norge TDA2030(Genuine) based amplifier . Tested up to +/-20V on a dual SMPS . DM me , I have some good layouts.
PS Your LM3886 amp was a real beauty!

TDA2050 vs LM1875 performance tests to see which is the BEST​

Lam road stuff is pretty iffy.
My experience as of yday. Had 2 opa2134 left over so decided to use it in my diy headphone amp. Plugged in the first one and i saw much much larger dc offset in one channel over the other. Checked out the circuits again. All parts measured as they should. Re-seated the opamp. No difference. The moment i power on the amp even without the source playing i saw the imbalance. Luckily it was under 10mv so decided to plug in some really el el el cheapo headphones for a trial. The amp played. After an hour decided to plug in the second opamp and suddenly dc offset came within 1.5mv of each other(1.5mv and 3mv). The second opamp also played more like the opa2134. There was lower gain and more headroom on the volume control. Now I am sure the first one was a rebadged rejected piece. The second one may just be rebadged.

Same and very convincing printing on both opamps. 😂
 
Lam road stuff is pretty iffy.
My experience as of yday. Had 2 opa2134 left over so decided to use it in my diy headphone amp. Plugged in the first one and i saw much much larger dc offset in one channel over the other. Checked out the circuits again. All parts measured as they should. Re-seated the opamp. No difference. The moment i power on the amp even without the source playing i saw the imbalance. Luckily it was under 10mv so decided to plug in some really el el el cheapo headphones for a trial. The amp played. After an hour decided to plug in the second opamp and suddenly dc offset came within 1.5mv of each other(1.5mv and 3mv). The second opamp also played more like the opa2134. There was lower gain and more headroom on the volume control. Now I am sure the first one was a rebadged rejected piece. The second one may just be rebadged.

Same and very convincing printing on both opamps. 😂
From which shop did you purchased? I got genuine OPA2134 from RS components online. BTW JRC4556 is better suited for headphone amps application for driving loads from 32Ohms and above. OPA2134 is suitable for 600Ohms and above. only I have built many headphone amps incl Objective2 , CMOY and buffered CMOY
 
From which shop did you purchased? I got genuine OPA2134 from RS components online. BTW JRC4556 is better suited for headphone amps application for driving loads from 32Ohms and above. OPA2134 is suitable for 600Ohms and above. only I have built many headphone amps incl Objective2 , CMOY and buffered CMOY
I bought 2 from the shop next to CK electronics years ago just to bide time until the originals came in. I was experimenting with a new diy amp so used the lam road stuff.
Yes i have bought my other opamps from rs components too.

The opa2134 is used for gain and i have buf634 driving the headphones at the output. They dunk quite an amount of juice needed across the impedance range. I love these buffers, used them for years on end and am going to use their newer avataar buf634a.

Jrc 4556 is another good opamp that I want to try out. Thats on my list too.
The linear tech opamps are also really nice actually. Very balanced sound.
 
I bought 2 from the shop next to CK electronics years ago just to bide time until the originals came in. I was experimenting with a new diy amp so used the lam road stuff.
Yes i have bought my other opamps from rs components too.

The opa2134 is used for gain and i have buf634 driving the headphones at the output. They dunk quite an amount of juice needed across the impedance range. I love these buffers, used them for years on end and am going to use their newer avataar buf634a.

Jrc 4556 is another good opamp that I want to try out. Thats on my list too.
The linear tech opamps are also really nice actually. Very balanced sound.
NE5532 and JRC2068 are also very good in the buffer section, cheap jellybeans , so not much incentives in it for selling fakes
 
NE5532 and JRC2068 are also very good in the buffer section, cheap jellybeans , so not much incentives in it for selling fakes
Thats what I used to think as well but there is the TL072 and entry level opamps from other companies as well costing even less and all of them and especially the rejects from the assembly lines can be rebadged/reprinted and sold for a profit in markets like lam road.
Thats what a person familiar with lam road products told me once.

Yes, NE5532 has been the darling of audio equipment circuit designers for many years and reasons and to a point even the jrc 2068.
 
My build with genuine high quality (Keltron, Wima, Nichicon) parts.
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LM1875 is know for good sound quality probably because of second harmonics (Measurements are HERE)
Thanks and regards
 
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Why? Didn't like the sound?
I dont have quality speakers to judge sound. I tested this at friends place who has fridge size Cosmic speakers. But his placement was not good (middle of the room) and he only has bollywood songs collection, so cant confirm.
Regards.
 
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