Here It Is: The All Singing All Dancing HTMCPS

[HypnoToad]

Thanks for the update! Just to clarify on the recommendations....

Cap replacement at C5 & C19 with 2.2uF and resistors at R8 & R16 to 200k, am I correct? (there seems to be no other options I guess, but better to be sure than sorry)

I have all the parts in a bag, but I will update with new parts. I will be building few boards in next couple of weeks.

Thanks again for the update

You are correct. Here is a pic with the parts to replace marked in red to make sure everyone is on the same page.

As for the terminal blocks the part numbers are marked on the PCB. ED655/2DS They are available from DigiKey but any other small twin terminal block with 7mm leg spacing will fit.

http://www.digikey.com/product-search/en?x=16&y=17&lang=en&site=us&KeyWords=ED655%2F2DS

To save on shipping select USPS First Class mail for small orders it's about $3.00.

 

[Grainger49]

I second Toad's recommendation of First Class Mail. My last small order came in 3 days. It could only have been faster if I were in the same town. Oh, and cheap too!

 

[WntrMute2]

Thanks to HT my boards came the other day. Going to put a mouser order together this week. Anyone have pictures of their battery power supplies? I can easily follow the posted schematics but I wanted to see how others packaged theirs. I was thinking about a separate enclosure to make battery changes/charging easy. also, would my power supply WITHOUT the X-reg from my PhonoClone3 work or do I need to further regulate what enters the HTMCPS? Link is to the construction guide that includes the Power Supply in question.

http://phonoclone.com/diy-guide.html

 

[Kappaholic]

Hi All,

I just finished populating the HTMCPS board. Those fat resistors were little tricky to push through. I had to pull most of them from the belly side. It seems that the ones I got from Mouser are longer and fatter, both the body and the legs.

I wanted to test the phono stage out today but, I inadvertently had ordered the wrong value resistors for R2 & R10, got the 619k ohms instead of the 619 ohms. Hopefully I can fire it up on the weekend.

Based on the calculator, I should be using 33 ohms for R1&R9 and 619 ohms for R2&R10 for Denon DL301MKII spec:

Denon DL-301 MKII Specifications
Output: 0.4mV
Output impedance: 33ohms

Can someone please confirm the values? It would be greatly appreciated.

Thanks in advance.

 

[Pio1980]

Does the automute on most TTs cause problems with this device?

 

[Kappaholic]

HTMCPS build completed, almost.

In anticipation for delivery of the correct R2&R10 resistor order from Mouser, worked on the enclosure today for HTMCPS. Unfortunately, the order hasn't made it home, yet.

After some practice on the CNC build, this build was much quicker and easier. I am really enjoying how this project is shaping into.

Some pics:

Thanks again for sharing this great DIY!

 

[Kappaholic]

The resistor for R2&R10 arrived today and gave the phono stage a spin with denon DL-301MKII.

I had few issues to start off. It wouldn't run on +/-12v for some reason. I got the +/-6V set-up with 8 AA batteries from the CNC to make it sing. Also had trouble with 2134 opamps as it makes static and distortion noise as if the battery is running out. I will have to check the 2134 opamps on the CNC phono stage to confirm if the opamps aren't blown. I will carefully check over the set up again tomorrow to see if any of the set-up or component is at fault. It's currently running on pair of LME49990 on dual SOIC adapters and sounds nice so far. It seems the output volume level is bit higher and there is noticeable hiss.


Anyway, I need to have the whole set up to burn in to see what it can.

 

[WntrMute2]

You are correct. Here is a pic with the parts to replace marked in red to make sure everyone is on the same page.

So is this the current recommendation for all HTMCPSs? C5 & C19 from 1.5uf to 2.2uf and R8 & R16 from 75K to 200K? Any other part changes before I order?
Thanks

 

[Kappaholic]

I have HTMCPS running with latest update above by Hypnotoad with replaced value resistors & caps and it is singing nicely. Never tried with 75k resistors & 1.5uf caps, but 200k & 2.2uf set up has nice deep & low extended bass.

 

[shelly_d]

I have looked through this looking for two things and have not found them. First is the answer to this question: Is this just a head amp designed to boost the low output of MC cartridge to levels handled by normal MM preamps or does it provide all the gain and equalization needed?

Second: is there a schematic available?

Thanks all

Shelly_D

 

[Fasterdamnit]

it is a complete RIAA EQ phono pre-amp for LOMC.

You will have to ask Sir Toad for the schema. :yes:

 

[HypnoToad]

I have looked through this looking for two things and have not found them. First is the answer to this question: Is this just a head amp designed to boost the low output of MC cartridge to levels handled by normal MM preamps or does it provide all the gain and equalization needed?

Second: is there a schematic available?

Thanks all

Shelly_D

It's a fully fledged MC phono stage as Jim said, also the schematic was in my head and I just put it into the PCB program and made changes from there.

 

[HypnoToad]

Kappaholic that's a fantastic looking build. It should be dead silent running on batteries.

 

[Kappaholic]

Kappaholic that's a fantastic looking build. It should be dead silent running on batteries.

Thanks for the kind words. I should try using two 9V batteries to see if some of the distortion may be associated with using AA batteries.

I will be using the OPS power supply, will try to hook it up over the weekend and see.

BTW, can you please check if I am using the proper input/output resistors?

Based on the calculator, I should be using 33 ohms for R1&R9 and 619 ohms for R2&R10 for Denon DL301MKII spec:

Denon DL-301 MKII Specifications
Output: 0.4mV
Output impedance: 33ohms

Thanks

 

[HypnoToad]

Thanks for the kind words. I should try using two 9V batteries to see if some of the distortion may be associated with using AA batteries.

I will be using the OPS power supply, will try to hook it up over the weekend and see.

BTW, can you please check if I am using the proper input/output resistors?

Based on the calculator, I should be using 33 ohms for R1&R9 and 619 ohms for R2&R10 for Denon DL301MKII spec:

Denon DL-301 MKII Specifications
Output: 0.4mV
Output impedance: 33ohms

Thanks

Your calculations are correct, try swapping out different op amps, like I said I am using OPA2134's and its dead quiet. Some op amps are not compatible in the input stage.

 

[philviral]

How similar is this to the Phonoclone, Mr Toad? Soundwise and design wise? I know you came up with it shortly after your Phonoclone experiments, so I assume it's pretty similar.

You've been living with it for quite a while now, which says a lot!!! I'd be interested to hear more about your impressions, after all these months.

 

[Kappaholic]

Your calculations are correct, try swapping out different op amps, like I said I am using OPA2134's and its dead quiet. Some op amps are not compatible in the input stage.

Thanks for confirming the resistor values. Yes, the paired OPA2134's & LME49720's are dead silent on HTMCPS, but I've been favoring the paired performance of LME49990 on both CNC & HTMCPS. Some noticeable static distortion is only with paired LME49990's on my HTMCPS build only. On the CNC, however, I was hearing similar (little more louder) distortion with paired LME49720's only at the input socket. I've ordered 15pF mica caps to see if it may be associated with RF pickup. Should have the orders delivered by this weekend for testing.

Thanks again for checking on the resistor values.

 

[HypnoToad]

How similar is this to the Phonoclone, Mr Toad? Soundwise and design wise? I know you came up with it shortly after your Phonoclone experiments, so I assume it's pretty similar.

You've been living with it for quite a while now, which says a lot!!! I'd be interested to hear more about your impressions, after all these months.

The HTMCPS is different in that it has a completely different RIAA setup, dual channel op amps, is designed primarily to run on batteries, has less components and different component values.

The latest version of the phonoclone now has battery connections and bypass caps on the filtering caps like the HTMCPS.

It is a transimpedance design though, which has been around for years.

Soundwise I think my design is better but then again I might be biased.

 

[shelly_d]

I tried reverse engineering the circuit from the images of the circuit boards.(so I could understand a bit of what was going on). HypnoToad, I hope you don't mind.

Here is what I came up with:

Is this correct?

It is not a type of circuit I am familiar with and when I try to simulate it in Multisim I get nasty output. (Put in a sine wave and get square wave out.)

Thanks

Shelly_D

 

[HypnoToad]

That's it, it's a transimpedance circuit or a current to voltage converter.