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Here It Is: The All Singing All Dancing HTMCPS

Pio1980 said:
So where are we on this thing?
Click to expand...

Many thanks to Sachin (Sachu888) and a combined effort from India Express Post and US Customs these arrived yesterday. :thmbsp:

They are 3" x 4", the same size as the CNC PCB's.

HTMCPS-1.jpg
 
Here's mine with the parts I had on hand I was short one cap but they are on the way, I found these neat little clip in stand offs at Mouser as well, they give 10mm clearance.

HTMCPSPartStuffed.jpg
 
I found another cap and put in the OPA2134's, wired it all up and giving it a test run.

This has got to be the best sounding phono stage I have heard.

It's simple, cheap to build and has only 10ma's current draw, what else could you ask for?
 
It Lives!

It is a contender!

Did some Op-Amp rolling and so far a pair of OPA2134's sound best. Played with a single AD823 I had in first and second socket coupled with a single 2134. It really sharpens the detail but too much- the upper mids and highs are really in your face. It also lost some lower bass. But if detail is what you crave above all else- use it. I tried a set of LME49990's on an adapter but it was fuzzy on one channel- works fine in other pre-amps. Same with an LM4562. :headscrat
A single LM47920 and 2134 was closer to a pair of 2134's- but lacked a tiny bit of dynamics.
And somehow I managed to delete the resistor mounts off my order from Mouser.

I need it give it some time to settle in before a serious A/B with the Hypnotoad Clone of a Clone MC phono stage. Very promising so far.


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Denon DL-304
I am the walrus...

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I mounted my HTMCPS in a proper case, not that the plastic kitchen storage container didn't do the job, its nicer looking. I purposely made the PCB layout spacious and functional. The ceramic supply rail bypass caps are as close as I could get to the power pins of the op amps so no chance of oscillation.

Jim, I just had a shootout with my PC3 original with OPA27's. The HTMCPS is much better, not sure if it's the 27's but it's much more detailed, everything is clearer. The PC3 has the typical BB laid back sound but too much so IMO and sounds cluttered in comparison with the HTMCPS with OPA2134's. I found like you that the AD823's are too forward. They may work well in other systems but not mine.

But for sure this is a great stage and only uses 10ma's against 15ma's of the PC3, which is 50% longer battery life and there is only 33 components in this thing. It has more gain than the PC3 as well so really low output carts should be no problem. The OPA2134's were never my favorite opamp but in this they sing. :banana:

Sachin, (Sachu888) needs a special mention the PCB's that he had made for me are first class IMO.

HtmcpsFin.jpg
 
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HypnoToad said:
I mounted my HTMCPS in a proper case, not that the plastic kitchen storage container didn't do the job, its nicer looking. I purposely made the PCB layout spacious and functional. The ceramic supply rail bypass caps are as close as I could get to the power pins of the op amps so no chance of oscillation.

Jim, I just had a shootout with my PC3 original with OPA27's. The HTMCPS is much better, not sure if it's the 27's but it's much more detailed, everything is clearer. The PC3 has the typical BB laid back sound but too much so IMO and sounds cluttered in comparison with the HTMCPS with OPA2134's. I found like you that the AD823's are too forward. They may work well in other systems but not mine.

But for sure this is a great stage and only uses 10ma's against 15ma's of the PC3, which is 50% longer battery life and there is only 33 components in this thing. It has more gain than the PC3 as well so really low output carts should be no problem. The OPA2134's were never my favorite opamp but in this they sing. :banana:

Sachin, (Sachu888) needs a special mention the PCB's that he had made for me are first class IMO.
Click to expand...

Nice! Fess up- where did you get the perfectly sized case?

I agree, Sachin has provided a great PCB at a killer price- Bravo!

I put Burr Brown OPA134's in the PC3 and the dynamics are firmer, bit more bass than the 27's. Once I get over this cold and my head and ears clear up, I will give them a serious A/B in a new thread. Next up- I need to find my Rhapsody in Blue and see how it handles Gershwin. Dire Straits, Love Over Gold was just wonderful last night. :music:
 
Fasterdamnit said:
Nice! Fess up- where did you get the perfectly sized case?

I agree, Sachin has provided a great PCB at a killer price- Bravo!

I put Burr Brown OPA134's in the PC3 and the dynamics are firmer, bit more bass than the 27's. Once I get over this cold and my head and ears clear up, I will give them a serious A/B in a new thread. Next up- I need to find my Rhapsody in Blue and see how it handles Gershwin. Dire Straits, Love Over Gold was just wonderful last night. :music:
Click to expand...

I got the case at Fry's Electronics and just love the little standoffs from Mouser, it just clips in and out. I listened to Love Over Gold as well, nice album, Dire Straights at their best.

The terminal blocks for the resistors are only at DigiKey.
 
This thing is a big hit here in India.I had kept 15 boards for this and none left,not even for me.This is a great DIY phonostage and can be built for very few $$$.It has very few parts and perfect for first time DIYers.
Everyone should build it,Thanks Hypnotoad for introducing this to us.

Regards,
Sachin
 
EchoWars said:
What's the reasoning behind that? You're using opamps, you can have the output impedance be anything you like...
Click to expand...

If I make it lower I have to have bigger DC blocking caps, and I want to use polypropylene.

With 1.5uf and 75k I have a corner frequency of 1.4hz.

Should I change it?
 
Where's a schematic?

The output impedance should be as low as possible. It has no effect on the corner frequency...only the input impedance of the next stage in line determines that (i.e., whatever you're plugging this little critter into).
 
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EchoWars said:
Where's a schematic?

The output impedance should be as low as possible. It has no effect on the corner frequency...only the input impedance of the next stage in line determines that (i.e., whatever you're plugging this little critter into).
Click to expand...

Here's the output setup:

OutPutCaps.jpg
 
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