Sparkos Labs BA312-M modules,

[Jflijohn]

I would really like to see an accurate test performed on a fully recapped system with the new BA316M, just raw numbers and no subjectivity.
Here is some pretty cool test equipment to rent. I’m guessing that even renting is out of my budget.
https://www.axiomtest.com/Analyzers...stem-Two-Cascade-Audio-Analyzer,-Dual-Domain/

And test methods
https://www.eetimes.com/document.asp?doc_id=1274861

 

[Steven Tate]

And test methods
https://www.eetimes.com/document.asp?doc_id=1274861

Great article! I’m getting a Quantasylum QA401 Audio Analyzer for Christmas (wonder how Santa knew I wanted it?). This article will give me some good info to experiment with. I have a newly recapped 2275. If I get ambitious, I might try a before and after THD test with whatever is the latest version of the new component. My bias is that I am skeptical of measurable improvement in actual operation.

 

[Jflijohn]

Great article! I’m getting a Quantasylum QA401 Audio Analyzer for Christmas (wonder how Santa knew I wanted it?). This article will give me some good info to experiment with. I have a newly recapped 2275. If I get ambitious, I might try a before and after THD test with whatever is the latest version of the new component. My bias is that I am skeptical of measurable improvement in actual operation.

I’m just curious if the QA401 arrived as expected and, if so, youve had a chance to play with it?

 

[bryans12v]

I've had my eye on that unit as well. Haven't really navigated the tractor software yet however.

Be careful with it on high powered units. Its rated at only 50 watts RMS but can handle short 300w peaks apparently.

 

[Mjölnir]

I'm currently upgrading my Marantz 2285 receiver, one of several Marantz units in my collection. Sofar I've completed upgrading the power caps to 18,000uF and the P800 power supply board (with guidance from Mburas excellent thread) and my last step has been the PE01 tone board. This step did not only include upgrading components but also replacing the BA312 IC's with Sparkos Labs modules. I have been comparing Sparkos vs. Burson modules but in the end realized that only Sparkos could fit into the confined space. The reason I left the Sparkos modules for last was that I wanted to evaluate them without having them masked by inferior components in the circuit. This project has been quite time consuming but also very rewarding. The major issue has been to select new components not only for quality but also for size since the space for the board is very confined in all three dimensions. Each step of all all nine steps included listening to alternatives before final selection of the new components. The final solution included a smaller PCB board (on standoffs) holding the six large Wima caps for the output stage and the location was the only way to squeeze them into the confined space with less than 1mm to spare. If space allowed I would have choosen Wima MKP10 for all signal line caps. A major part of the upgrade was replacing all film and elyt caps < 10uF with polypropylene caps and bypassed with polystyrene caps.

For the testing of each of the nine steps I had to isolate the tone board by using an external high quality signal source and for output a Mark Levinson 23.5 power amp. I used two references for A-B testing, the preamp part of my Marantz 2285B (not upgraded) and my favorite Audio Research preamp.

The nine steps in following order followed by A-B listening tests after each step:

1. Replacing all four transistors with Fairchild KSC1845 for HE03/HE05 and KSA992 for HE04/HE06
2. Replacing all ceramic caps with Kemet MLCC caps
3. Replace input caps CE05 and CE06 with 1uF/250V Wima MKP10 caps, bypassed with 0.1uF polystyrene caps
4. Replacing all other polyester film caps with Wima MKP4 polypropylene caps bypassed with 0.1uF polystyrene caps
5. Replacing all Elyte and Tantalum caps in the output stage with Wima MKP4 polypropylene caps bypassed with 0.1uF polystyrene caps. Wima caps are fastened with hot glue on a smaller pcb board on standoffs.
6. Bypassing all new signal path polypropylene caps with 0.1uF polystyrene caps
7. Install Sparkos Labs discrete modules
8. Trying out Nichicon FG,KZ and Elna Silmic II for the CE09/10 47uF and CE 13/14 10uF caps, eventually selecting the Silmics.
9. Bypassed the four Elyt caps with 0.1 uF polystyrene caps.

Not surprisingly all steps yielded an audible improvement. By each step sound became increasingly more spacious, detailed and refined. Details and instruments I haven't heard before became clear. Also the sound stage became more laid back. The steps that yielded most noticable improvement were 4, 5 and 7. All polypropylene caps in the signal path and 7. Sparkos Labs modules replacing BA312 IC's. Quite noticable improvement were made by bypassing polypropylene caps in stage 4 and the Silmic caps in step 8 with polypropylene caps.
In the end the difference between the preamps of my 2285 and 2285B were night and day (they were pretty close before). The 2285 preamp came close depending on the music material. Sometimes it was hard to tell the difference. Nevertheless I think my 2285 PE01 board would classify as a high end preamp in today's market.
Finally, I don't know what my evaluation of the Sparkos modules would be had I started installing them in step 1. Old and inferior components might have masked their performance and instead made step 4 and 5 even more significant. My advise, if you install the Sparkos modules then you should also replace all film caps with polypropylene caps for best effect. They are worth it.

After step 4


After step 5.


Final board with Sparkos modules.

 

[bktheking]

I am currently in the process in restoring and upgrading my Marantz 2285. On AK I've come across SparkoLabs module to replace the dated BA312 IC. From previous experimentation I've found the Burr-Brown OPA627 to be the best sounding IC for audio purposes. Has anyone tried the adapter from Vintage Audio Adapters (with the same pin configuration as TA 7136) where you can use any 8-pin IC of your choice. This option is also less expensive (the adapter costs $9.99 on eBay). I'm inclined to go this route but first I would like to hear from anyone who has tried and compared these two options.

View attachment 1274455

Has anyone went this route ^^^ - the sparkos stuff looks good and i admire his dedication to the hobby of finding alternatives but very spendy to replace a pair of opamps, performance slight improvement or not. $20 in adapters and $5 in opamps seems more reasonable.

 

[Mjölnir]

Yes, I tried the adapters + OPA627 opamps (total cost is about the same as Sparkos modules) and didn't notice very much difference. Since Sparkos modules had good reviews I decided to try those while at the same time do a complete upgrade of all the caps.

 

[bktheking]

Can a less costly op amp be used , didn’t realize that model was so expensive.

 

[Mjölnir]

Of course you can use less expensive opamps, but I think OPA627 or OPA827 are the best sounding (from those I've listened to) and they have a very good reputation for audio use. But if you know anything better then please let me know.

 

[Steven Tate]

I’m just curious if the QA401 arrived as expected and, if so, youve had a chance to play with it?

I did get the QA401 by Christmas. Unfortunately, I came down with the flu the day after Christmas and am just now getting my body back in action. It is an evil bug this year. I have downloaded the software and am waiting for a little free time to get familiar with the analyzer.

 

[sanjith]

I'm wondering if anyone met with any issues after installing BA312 module from Sparkos Labs or Noah Schumacher on a Marantz 2325 unit?

Me and a friend of mine bought the upgrade module from Noah Schumacher about a year before. The upgrade work on my unit was done by a well known technician. When I received the unit back, I have noticed that the relay clicks after few minutes when I switch on the unit. Most of the time it will be playing music so music stops for 2 secs ... relay clicks back and the music continues. So I have given the unit back to the tech to find the issue but unfortunately he couldn't find the exact issue even after 1 month. He said its really tuff finding the issue as it happens rarely and everything looks fine when he checked the unit.
Anyway, I collected the unit back from him as I got irritated since the unit was there for 1 month and he could'nt find the issue.

I started working from my side. Tried connecting a different preamp to the unit .... played it for few days and it never showed the issue. Connected a different power amp to the pre out of the unit and the relay clicked on the power amplifier. It was a horrible experience dealing with Noah Schumacher when reported this issue for support. In between when speaking with my other friend (who did the same upgrade on his 2325) I mentioned this issue ... and came to know that he is also going through the same issue and thought it is just for him on his unit because of something else.

But after a month I tried contacting Andrew from Sparkos Lab for any inputs. He is a gentleman who have told me to try few changes in capacitor values. Tried them, initially it seemed everything is fixed but the issue continued. Andrew even sent me another set of module for free which did'nt fix the issue too.

So I assumed the issue is with the PE01 board. Pulled the upgraded BA312 module out and reverted back to the original module which didn't fix the issue.
Then I started searching for another PE01 board in mint condition. Recently I was lucky to find another PE01 board and replaced the board in my 2325. But still the issue continues....

So I don't believe its because of the BA312 upgrade but at the same it is strange that both the units have got exactly the same issue.

 

[Jflijohn]

I have no experience with Noah Schumacher or Hallo-fi but there is lots of data on the web beginning with this from the Better Business Bureau hhttps://www.bbb.org/us/co/boulder/profile/car-stereos/hallo-fi-electronics-0694-1000022263

I do have experience with the BA312 on a 2275 PE01 board. I am not an experienced technician, strictly a beginning hobbyist. Following the supplied instructions I successfully installed the BA312 out of necessity as I blew up the original op-amp. Instructions were clear and the installation was a major success however, on this particular unit, I am playing it through the pre-out into a Mcintosh power amp. I don't even have the P-700 power amp boards installed. I believe the P-700 (L+R) along with the P-800 power board are what activate the relay. I would suggest disconnecting both P-700s (disconnect completely, not just using the pre out) to see if the issue goes away.
The boards I'm referencing are for the 2275, they may differ from the 2325 but, I think its the same general idea

 

[Drugolf]

Just got back my 2285 from my tech after he installed the Sparkos BA312-M kit. Sounds fantastic!

 

[goldswimmerb]

I'm wondering if anyone met with any issues after installing BA312 module from Sparkos Labs or Noah Schumacher on a Marantz 2325 unit?

Me and a friend of mine bought the upgrade module from Noah Schumacher about a year before. The upgrade work on my unit was done by a well known technician. When I received the unit back, I have noticed that the relay clicks after few minutes when I switch on the unit. Most of the time it will be playing music so music stops for 2 secs ... relay clicks back and the music continues. So I have given the unit back to the tech to find the issue but unfortunately he couldn't find the exact issue even after 1 month. He said its really tuff finding the issue as it happens rarely and everything looks fine when he checked the unit.
Anyway, I collected the unit back from him as I got irritated since the unit was there for 1 month and he could'nt find the issue.

I started working from my side. Tried connecting a different preamp to the unit .... played it for few days and it never showed the issue. Connected a different power amp to the pre out of the unit and the relay clicked on the power amplifier. It was a horrible experience dealing with Noah Schumacher when reported this issue for support. In between when speaking with my other friend (who did the same upgrade on his 2325) I mentioned this issue ... and came to know that he is also going through the same issue and thought it is just for him on his unit because of something else.

But after a month I tried contacting Andrew from Sparkos Lab for any inputs. He is a gentleman who have told me to try few changes in capacitor values. Tried them, initially it seemed everything is fixed but the issue continued. Andrew even sent me another set of module for free which did'nt fix the issue too.

So I assumed the issue is with the PE01 board. Pulled the upgraded BA312 module out and reverted back to the original module which didn't fix the issue.
Then I started searching for another PE01 board in mint condition. Recently I was lucky to find another PE01 board and replaced the board in my 2325. But still the issue continues....

So I don't believe its because of the BA312 upgrade but at the same it is strange that both the units have got exactly the same issue.

Sounds like a power supply related issue, I would see if you can get it to do it and monitor the output voltage of the regulated section to the preamp section, the SparkOS models are very sensitive to the input voltage from what I've seen.

My experience with them has been generally positive, however I have noticed some units (post upgrade) develop an issue with DC on the tone control for around 30 seconds to a minute following start up, just causing a minor pop when turning the tone control on/off or changing the low mid high pots. Just a mild inconvenience that I'm almost certain just has to do with coupling caps charging.