Optical cartridge phono equalizer circuit info


Click here for information on the phono equalizer circuit for optical cartridges.

Optical cartridge phono equalizer circuit info

Please refer to the spec sheet of the photo detector used for the optical cartridge.
HPI623(Grand Master,DS003)  

HPI2464(DS Master1,DS-W2,DS002,DS-E1)


↓Interview from Japanese audio magazine.
Answered by Tetsuaki Aoyagi DS Audio CEO 2021/3

What is the true meaning of DS Audio publishing phono equalizer circuit information for optical cartridges on the web? 

Q, Why did you decide to publish the confidential information of the phono equalizer circuit for optical cartridges on the web?

The bottom line is that we want to change optical cartridges from “unique” cartridges to “popular” cartridges.
Since the launch of DS Audio, we have been working with the goal of popularizing optical cartridges as the third cartridge after MM / MC cartridges. Thanks to you, the number of customers who use optical cartridges has increased in the last 7 years, but optical cartridges are still one of the “unique” cartridges, and it cannot be said that they have become “popular” cartridges. We believe that more phono equalizer “choices” are needed for our customers in order to further popularize optical cartridges in the future.
With the emergence of phono equalizers for optical cartridges from various companies, the new appeal of optical cartridges will be brought out, and customers will be able to choose products that better suit their tastes. We believe that this “choice” is absolutely necessary to make optical cartridges more popular.
As you all know, there are brands such as Soulnote’s E-2 and EMM Lab’s DS-EQ1 that are equipped with an equalizer for optical cartridges. I hope that more companies will continue to develop equalizers for optical cartridges.
Therefore, if the manufacturer develops an equalizer for optical cartridges, we will provide all technical support free of charge, and there is no need for license fees or inspection costs for commercialization. As soon as we actually publish this information, we will try to make a prototype from an overseas brand, so we have received direct inquiries asking for more information.
Also, I would be happy if not only manufacturers but also those who would like to personally create equalizers for optical cartridges using this circuit information. However, I’m really sorry, but we cannot afford to answer individual questions about the circuit from our customers due to our manpower problem, so we would appreciate it if you could understand that point.

Q Do you want to unify the standards for phono equalizers for optical cartridges?
Yes, that’s right. The cartridge requires a completely different power supply method depending on the LED and photodiode elements used. Therefore, the photoelectric cartridge 50 years ago became a phono equalizer specification of each company and was not standardized at all.
If this happens again, not only will it be very inconvenient for our customers, but the optical cartridge will not be a “popular” cartridge for the future. For that reason, we would like to publish the standard of phono equalizer for optical cartridges and create a foundation for everyone to compete for products within the same standard.

Q Are there any disadvantages when other companies’ products come out?
Certainly, there was an opinion that it would be better to stop because other companies will commercialize equalizers for optical cartridges and some people will not choose DS Audio equalizers. This is only a very short-term perspective, and from the perspective of popularizing optical cartridges, this is wrong, and I think it would be better if more phono equalizers for optical cartridges appeared on the market. This will bring out more of the appeal of optical cartridges and give customers the pleasure of “choosing”.
Also, personally, I think it would be better for a company that makes optical cartridges to come out.
I think that more companies should create better products for optical cartridges and equalizers for optical cartridges within a common standard.

Q Do you envision a future in which you can compete with other cartridge manufacturers for the sound of optical cartridges?

I think that is better.
I personally don’t consider other cartridge or amp makers to be competitors at all.
Audio is a hobby product and is a competition for disposable time for customers.
Our real competitors are not only other hobbies such as fishing, golf, cars and games, but now SNS is also our competitor.
It is important to create attractive products that are competitive with other hobbies like this. For that reason, I think the most important thing is to create attractive products for the entire industry by holding hands rather than competing within a small industry. From that point of view, other cartridge makers and amplifier makers should be in a position to hold hands rather than competitors. It would be great if various companies could use their respective technologies to bring out the appeal of optical cartridges and make audio for customers as attractive as possible.
For such a future, we will work hard every day to get people to say that DS Audio products are the best.