BBD Chips: The Heart And Soul Of Analog Delay

Everyone who loves analog delay has encountered this term sooner or later. You hear it constantly in reviews and it is always in the back of your mind. But, what is it?

In short, BBD simply means Bucket Brigade Device and is a term used to define a certain type of technology being used. In this case, it’s for producing repetitions. You see, in the delay world, you mainly have to great contestants: digital delay and analog delay. BBD technology is what defines the analog counterpart.

The idea behind this post is to properly explain this concept and to see why it is still vital for having analog delays. I will also try to hover on some of the most famous chips used, and the delays that made them famous (or is it the other way around?).

Let’s go.

BBD: A Better Definition

The definition provided during the initial paragraphs was kind of loose. It’s time for a better and more comprehensive one.

As stated before, BBD stands for Bucket Brigade Device. It is a circuit (Integrated Circuit or IC if you want to sound fancy) that is usually enclosed in a small chip. This chip contains a series of capacitors that are used to carry or pass on the sound signal. It also contains transistors which act like timers, ordering the capacitors when to pass the signal previously received. Finally, a BBD chip has another companion chip that works like a clock; it tells the transistors the rate at which the capacitors should pass along the signal.

As you may already guess it, this technology is not new. It was developed during the late ’60s (between 1968 and 1969) by Sangster and Teer of the Philips Research Labs. At the same time, another alternative was being tested. It was called CCD as in Charge-Coupled Devices. It was developed by AT&T Bell Labs and it was in many ways, better than the BBD technology.

In the end, BBD chips prevailed because of their simplicity and lower costs (at least for delay units). Sadly, I don’t know much more about this story, so If you are tech savant, please share your knowledge on the comments.

Pass Me Another Bucket!

The term “Bucket Brigade” has an interesting connotation and actually, it helps to explain how this chip works. I’ve briefly discussed it on a previous post, but I think is worth giving it another try.

Bucket Brigade refers to the old technique of passing buckets of waters. It was mainly used by firefighters to put out the fire, prior to the advent of modern equipment. Obviously, this technique had its shortcomings and every step of the way, the buckets will lose some water. So, the longer the chain, the further the buckets had to be passed on and thus, resulting in more water loss.

Bucket Brigade Technique — **Image 1:** A typical example of the bucket brigade technique.

That’s exactly what happens with these chips!

The capacitors in analog delays are like the buckets. They receive information (sound signal), they store for a little while, and then they pass it along. So far, so good, right? Well, not so much. Capacitors are not perfect and they tend to “leak”, like a bucket with a small hole.

Because there’s a loss of information, each new capacitor receives a little less, and a little less, and a little less… you get the idea. This is why when you apply long delay times on these devices, you get distorted, darker and imperfect repetitions. The longer the delay time, the more imperfect the outcome.

Filtering The Noise

Another common characteristic of BBD chips is that they produce noise. This mainly comes from the clock (the companion chip) which dictates the rate at which the signal should be passed from one capacitor to the other.

The usual way engineers dealt with that was through low-pass filtering. This simply means that they try to minimize the higher frequencies on the sound being produced. By doing this a desirable side-effect was achieved: the repetitions sounded duller (less bright) but also “warmer”, which is a classic analog delay characteristic. That’s why sometimes you can “analogize” a digital delay by simply rolling off the higher frequencies.

Famous BBD Chips

We need to start from the very beginning here. The chip developed by Phillips in the late ’60 was named TDA 1022. Later on, Phillips decided to license the technology behind it and other companies started developing their own version.

One of such companies was Reticon Corporation, from California. Their SAD chips (Sampled Analog Delay) where pretty much used everywhere, especially for modulation effects.

The other company was Matsushita, from Japan. If the name doesn’t ring a bell is because in the West they are better known as Panasonic. Phillips also decided to license their tech to them, and they developed the famous MN3000 chips.

Panasonic BBD Chip — **Image 2:** The famous Panasonic BBD MN 300x Chip.

Today the original BBD chips are kind of hard to find. This is mainly because Reticon stopped producing them in the early ’80s. Panasonic also stopped producing them in 1999. So that left the market with no current new supply. So, where do we get BBD chips for our delays these days?

Current Production

Well, companies soon noticed that there still was some demand for these chips, so they came up with their own clones. One of such companies was Beilling, from Shangai. They label their chips with the nomenclature BL, so for instance, when you see something like BL3208, then you know this chip is from them.

Other companies that also do the same are Behringer and Cool Audio. And the most recent one has to be Xvive Audio. They have their own version of Matsushita’s MN3005. They are also known for having a product called W3 Memory Analog Delay. This pedal has their MN3005 replica in it and was engineered by Howard Davis (the man behind the Deluxe Memory Man).

NOS BBD Chips

There’s also something called New Old Stock chips (NOS). These are original chips from the manufacturers that for some reason have been stored all these years. Some companies kept a stack of them (like EHX), some people had a few, there are also second-hand chips… you get the idea. Because of the current demand, these old boys are now being released, and you can now buy them in some places.

I’ve checked a little bit about this and you can get them on eBay and also a site called retroamplis. This is great for sure if you have a project where you would like to test these chips. Maybe you want to mod your delay and use them to get the original BBD feeling.

Like always, you should be really careful about buying tech on the internet, especially when they are old! Remember, this is pretty much vintage stuff and you should try to be as sure as possible whether these chips are still working or not.

Pedals With NOS Chips

Let’s face, as guitar players are obsessed with tone, and vintage gear is almost mythical. Because of this, some companies considered offering pedals with NOS BBD chips. Remember that EHX was one of the few with a bunch of NOS chips? Well, they had the Deluxe Memory Man 1100 Tap Tempo. This first version of the pedal had the original Panasonic MN3005 chips.

I think the demand for this pedal was considerable, so EHX ran out of their batch of original chips (or maybe they just wanted to keep and strategic reserve, who knows). To countermeasure this issue, they decided to use a replica of the MN3005 chips made by Xvive Audio (yep, the same guys behind the W3 Delay). So if you look closely, the new pedal is called Memory Man 1100 TT, instead of “Tap Tempo”. So if you still want to get the Panasonic chips, you should hunt for the older version fo this pedal.

Deluxe Memory Man Tap Tempo — **Image 3:** This is the version of the DMM with the NOS Panasonic BBD chips.

On the other hand, a company called Chase Bliss Audio decided to take another path. They’ve considered that the BBD replica chips produced by Xvive were good enough and built an analog delay using these components as a base. The result? The Tonal Recall Analog Delay.

This has to be one of the most powerful analog delays ever created. I’ve talked a little bit about this pedal on this post, so I encourage you to check that out. I will also leave a link on the resources section so you can read a more in-depth review of it.

The Verdict

The fact that EHX decided to replace their Panasonic chips with the Xvive replica speaks volumes about the quality of it. It is also interesting to note that a pedal like the Tonal Recall was engineered around the Xvive MN3005. At the end of the day, I think it comes down to a matter of preference, but I’m not going to lie, I think having those original BBD MN3005 on your pedal must feel legendary!

I will put a link on the Resources section so you can read an article about the differences between the TT version and the Tap Tempo version of the Deluxe Memory Man. So, give it a look and let me know your thoughts on the comments section.

The Very First BBD Analog Delay

Here’s where it gets tricky. There is a lot of buzz around the very first analog delay with these chips.

For some time Mike Mathews -the founder of EHX-, declared the Memory Man as the very first analog delay pedal. My guess is that for this to be the truth, this pedal had to be around 1976 or 1975. This was somehow confirmed Howard Davis, who stated that the pedal was in the market for some time previous his arrival in the company in 1976. The Memory Man used the very sought after Matsushita MN3005 BBD chips.

Another contestant has to be the Dynacord EC 280. It is said it was introduced in 1977 and it utilized 8 Phillips’ TDA 1022 chips. This made in Germany pedal (oh nein, it’s Deutschland gegen den Staaten nochmal ;)) had really interesting sounds in it. I’ve listened to some demos and for me, sounds really unique.

Image 4: The famous 1977 Dynacord Delay (top) with the Phillips BBD chips.

What about BOSS pedals? Well, as you can imagine, the first one was the DM-2, right? Right? No, it was actually the DM-1 introduced in 1978. What’s interesting with this one is that it is supposed to run with CCD chips, not BBD ones. I’m not sure about this so if you have more information about this topic, please share it in the comments section.

Some Final Thoughts

The main idea behind this post was to offer some insight into the world of analog delay, especially that concerning the Bucket Brigade terminology.

I think it should be clear by now, but BBD chips are what makes analog delays special; I consider them the heart and soul behind their warm, dark sound.

It is also interesting to know that a type of technology that was once considered obsolete, is now returning. This “forced” guitar companies to include one more time, versions and reissues of their original classics (like the BOSS DM-2w). I also think that new chips and replicas of their older counterparts should be given a chance. After, this is what’s allowing us to keep having great products, isn’t it?

Until the next time,

M.M