Posts Tagged ‘Delay’

Way Huge WHE702 Echo Puss

Thursday, May 21st, 2015

WayHuge-EchoPuss

What is it?
Way Huge WHE702 Echo Puss. Made by Dunlop in 2010’s.

A guy offered this in a trade. And being the type of analog delay friend that i am, i had very little choice but to go for it. This is my first Way Huge box. While it isn’t the Way Huge that originally made the name, but a modern Dunlop factory pedal, i was somewhat enthusiastic. This continued all the way to the first test run. I’ll get back to that in a bit. As usual, i opened the unit up to see what was inside.

WayHuge-EchoPuss-guts

Standard two-sided Dunlop manufacturing read boards with ground fills, all the stuff board mounted and three boards connected with clip on terminals. At this point i didn’t have interest in taking it completely apart. Neat and modern, but dull, if you will.

About the design itself, we have an analog delay with modulation circuit with it. In addition to normal delay time, feedback and mix (called blend) controls, we have tone acting as a filter and two controls for modulation – depth and speed. The delay time is promised at 600ms. Quite impressive set of features for the price, right?

How does it sound?
But then comes the sound part of the unit. Sure, there ain’t that many crystal clean analog delays around. The ones that are are usually priced at higher range of the number on the price tag. And the reason is rather simple. The 600ms is your maximum delay time as advertised. But. I’d say the usable part ends with 280ms as anything over this time will result in BBD chip distortion. This distortion is rarely wanted and its texture isn’t very pleasing. The tone control can be used to hide parts of this distortion and by cutting highs i was able to go near 400ms without the distortion bothering that much. It will be present with the delay time knob over half way. This is the biggest culprit. The modulation works well and sounds very good on the repeats.

I’d say the price/sound/feature ratio is well balanced. After all, the analog delays that are actually good do not often come in this price range. Not bad. But nothing mind blowing or too good either.

Danelectro DSD-1 Shift Daddy

Wednesday, April 15th, 2015

DSD1-ShiftDaddy

What is it?
Danelectro DSD-1 Shift Daddy Echo Pitch Shifter from original series of rocker pedals. Made in china around late 90’s.

I must admit that i was interested. And local music store happened to have one left behind. The unit had seen better days as it had sat in direct sunlight for years. Still unused, but with visible ageing and discolouring. The photo below may not seem much, but the flames should be in a lot deeper red. Otherwise the unit is in great shape.

DSD1-ShiftDaddy-1

Had to snap a shot of the tail lights too. Some dust around the edges, but nothing that a moist rag won’t fix.

DSD1-ShiftDaddy-2

What comes to the features of this unit, we have something not so common. Or that’s how it seems at first. Sticker with “this ain’t a wah” suggests that we are in for a treat. Sure there are a few Danelectro designs that are out there and this does apply to Shift Daddy as well. Echo Pitch Shifter. What comes to mind first is a weird digital effect with mashed up features borrowed from Boss pitch shifters and delays. But actually. No. Although some may consider these as valuable tools, and are amazed by the weirdness, i must disagree to some degree.

DSD1-ShiftDaddy-3

Why? Because once i fired this up, i knew exactly what it was all about. The rocker simply controls the delay time of a PT2399 chip. So in other words, this is nothing more but a quite standard delay design where the delay time setting has been moved to a pot controlled by foot. Rest of the pots (feedback and mix) are replaced with push button switches that look like exhaust pipes. So in fact, there’s nothing even resembling a real pitch shifting effect. Just basic delay unit.

DSD1-ShiftDaddy-4

There you have it. I had certain hopes for it, but those all got stumped when i played with the unit. And checked the insides. From the feature point of view, this is sadly the dullest one in all three rocker pedals ever made by Danelectro. You know, there are real tool like delay units that accept the use of external expression pedal for the delay time. Usually those are way better all digital designs too.

How does it sound?
Decent, but not much to write home about. It’s a delay. Nothing more. And it’s a digital PT2399 based delay, so do not expect anything else. It does what it does in a good way, but there just isn’t nothing special about it’s tone. The delay time range of the chip isn’t that great for this type of application. When the delay times goes from something like 40ms to 400ms, the sweep acts just way too fast and this makes it just plain annoying to use. It’s not a pitch shifter. Just a delay with time control on a rocker. And it doesn’t do even that feature extraordinary well. Disappointing, but there is still a bit of Danelectro magic in there. Not the worst, but not good. Proceed with caution.

Excalibur AD-350 Analog Device

Wednesday, April 8th, 2015

Excalibur-AD350-AnalogDevice

What is it?
Excalibur Analog Delay AD-350 Analog Device. Made in china around 2006.

Someone i know was selling the lot of these Excalibur brand pedals. Local musician’s forum had no bad words, just a few descriptions about tone and such. The price for the three pedals was ok, including this (which was the most interesting one), the Tone Screamer and the Holy Grail Distortion. These three are apparently the only pedals in the Excalibur catalog. At first everything seemed ok with the slightly customized 125B-style enclosures and the original retail packaging.  Initial testing left me a bit puzzled. Why the representation in my are had seized and why the brand had never released more designs (slight edit/update: there have apparently been at least two design from the Biyang catalog, sold as Excaliburs in late 00’s). The testing and bang for buck ratio seemed nice, but i had still a few questions left in me. The box has several references to analog delay, but the first impression on tone left me feeling like something was a bit off. Brand promotes itself as a german brand and there are just overdrive, distortion and delay. If i’m worrying about nothing, then i’d definitely praise these things to the world’s end.

Excalibur-AD350-AnalogDevice-guts1

Had to open it up to see what was going on. The first impression was not that pleasing. Yup. This is not made in germany. Flux residue tells us everything we ever need to know about the board and component origin. If this isn’t chinese, i know nothing about pedal electronics. But that’s not all. Notice how the board mount plastic jacks are just floating behind the holes in the enclosure. And flip the board over…

Excalibur-AD350-AnalogDevice-guts2

And all i see is a regulator, one opamp, one through hole FET and a chip that is not an analog delay bucket brigade device. Let’s look a bit closer…

Excalibur-AD350-AnalogDevice-guts3

Yup. F this. It’ s nothing more than a standard PT2399 based delay that is slightly tweaked to sound more vintage, or in other words, bad. Not too great SMD construction and there we have it. No. I’m not pleased. I feel swindled. Not by the guy i got this from, but the Excalibur brand itself.

If we count the pedal itself and the box, there are 8 references to “Analog”. And since the PT2399 is definitely NOT an analog chip with its built-in high (or at least reasonable) quality AD/DA converters. After reading about this a bit more, the unit is apparently the same circuit we find in Belcat branded “Analog Delay”, another cheat in the market. There are others too, like the cheapo Artec Analog Delay, which all are PT2399 based digital delays.

Conclusion? Do your homework before you buy anything. You don’t want to end up like me with these three… Unless you just want to find out what these things are made of. That’s basically the only good reason to get one.

How does it sound?
Decent modelling of an analog delay. In a sense it’s worse than most PT2399 pedals, but that’s what you get when you try to use this chip for recreation of a true analog device. Stays clean on short delay times and dirties up on longer. No endless feedbacks or any other out-there features. Just basic delay. Not that bad sounding, but the lies just taint it up and bad.

No i don’t recommend any Excalibur brand pedals to anyone. Cheapest china crap peddled by a german business men. If you want the same tone, just grab the Blecat cheat for an “Analog delay” instead. You’ll get the same amount of street cred from me in both cases.

And no. This is not an analog delay.

Danelectro DE-1 Dan Echo

Sunday, March 22nd, 2015

DE1-DanEcho

What is it?
Danelectro DE-1 Dan-Echo from Danelectro original series. Made in china, late 90’s.

I had one of these back in 2000, but sold it at some point. Once i had a chance to get one back for reasonable amount of cash, i grabbed it. These are in no way rare or scarce and anyone should be able to get one if one feels like getting it. The design has remained the same since 1996, but i believe these have been manufactured for a long time. I’ve not heard anything new from Dano since the Cool Cat series. According to Wikipedia, the Evets corporation,  which revived the brand in the 90’s, is currently focusing in limited edition guitars. I’m thinking the well selling units are still in production, while R&D has been dropped.

DE1-DanEcho-guts1

As with all the other units with this type of enclosure, there are two circuit boards. The bigger one holding the PT2395-based delay circuitry, switching and controls, while the smaller one has the in/out jacks and power connections. Switching is our standard CMOS electronic switching found in almost every Danelectro pedal (except for Cool Cat series, which has mechanical true bypass in place. But for others..)

DE1-DanEcho-guts2

The designs seems to be somewhat close to the application example found in PT2395 datasheet. Sure enough, the chip will not function in any other manner and the board size does give some limits to what the unit can have inside. Solid construction with slight flux residue. While construction is solid, it is still looking a lot like an average work found in mini effects series. Done fast and cheap.

DE1-DanEcho-guts3

One thing that surprised me was the power. As with just about every pedal with  digital chip in them, we have the supplied 9V for the signal path and a regulated drop to 5V for the digital chip. Not in here. The 9V doesn’t connect to anywhere else but to a regulator input, marked as C201 in the jack board. The 9V does not get to the main board at all. Just the regulated 5V, which is then used for operating the switch, buffers and mixing – in addition to supplying the power for PT2395. JRC4558 used in mixing does work fine with 5V, but all this still surprised me a bit.

DE1-DanEcho-guts4

What comes to controls, this puppy has quite versatile options. Maximum delay time is somewhere around 700ms and the high cut control can dial the classic tape-style sounds. Delay time mode is set with a toggle switch, like the datasheet suggested. The delay time control is named “speed”, which suggest a modeling of tape echo units. The repeats control is tuned to act like pristine effects. No noisy, endless feedbacks. Just decent guitar echo. In general, i’d call this feature rich standard delay with just a few minor caveats.

How does it sound?
Overall – good, if not great. The high cut, mentioned above, makes a huge difference between Boss DD-3-like sharp, metallic digital delay and soft vintage-like tones. But for me, i find it rather useful to have both worlds in a single box. The controls are good and while the digital chip offers low noise operation for the delay itself, the 5V for the opamps tend to distort the signal pretty badly when the unit is used with high output pickups. For vintage and moderate output pups there is nothing wrong with the tone. Solid sounds and good controls, the best feel is present when used for vintage delay sounds.. Good unit, and when we take the current street prices of used units into account, we really can’t go wrong with this pedal. Just keep in mind that the headroom is what you can get with 5V and the operation sucks with modern pickups. There is a good reason for the level of popularity.

EHX Memory Man with Hazarai XO

Wednesday, March 18th, 2015

EHX-XO-MMwHZ

What is it?
Electro Harmonix XO Stereo Memory Man with Hazarai. Made in new york in early 10’s.

Got this unit used with a defunct tag in a trade. I was sort of skeptical as most of the modern EHXs are just plain dead and there is very little that can be done. But i went for it anyway, out of curiosity. Pedal was and is in decent condition with a few marks of use. Since the old school lab supply on my desk can only put out 100mA i figured this wouldn’t the one to be tested on that supply. After checking the manual, i set up one of my old power supplies with 500mA output and tried the pedal out. Nothing. No sign of life. Oh well. These things can happen and some trades leave me on the win anyway, so getting one brick isn’t going make much of a difference. Still i wasn’t convinced. I took out my modern favourite power supply that can put out 1A if needed and tried again. Took the pedal about 20 seconds to perform its power on self tests, but this time everything seemed to be running smoothly.

EHX-XO-MMwHZ-guts1

I do recall running into similar issues with other all digital designs. If the circuit is fed with too low current, things can get weird. Seemed like the case with this one. My guess is that someone had used low current supply and this has caused the digital circuitry to act in an undesired manner. Others could still think that the unit is broken and i’m not disputing that. It’ll work just fine if it has a power supply that’s capable of satisfying its needs. The damage has been done and it’s not getting any younger. But it works.

As the photos show, there is very little us lumberjack-style effect enthusiast can do if the pedal is really dead. This is partially a sad thing as the people qualified to repair these things are scarce when compared to old through hole manufacturing methods. Meaning that there will number of units that will get trashed due to not being cheap or viable enough to repair when something goes wrong. One of the biggest culprits of modern times. Unsustainability.

EHX-XO-MMwHZ-guts2

In heart of it all lies an digital signal processor manufactured by Analog Devices. Yup. I’d call that an oxymoron. Although AD chips and processors are top notch and those tend to be used for many audio applications. This design is all digital and size of the chip tells us that it’ll beat your Commodore 64 in a heartbeat.

Next up i was to try the unit out, now that it was working. Five pots with a digital rotary switch and two stomps. Unit can be used as a standard delay, but that will leave a load of features out. We have our multi tap and reverse delays in addition to the expected ones. The looper function is in there too. I must admit i had to search for a user maual to get any real testing out of it. If you want an overview of the features, i suggest you do the same. It would take me quite a time to explain everything, so let’s just get on with it.

How does it sound?
Pristine. Designed in a manner that the unit could be usable with synths and organs as well as with guitars. Frequency responce doesn’t discriminate and the buffering at the beginning of the signal path doesn’t care wether you push it hard or with vintage guitar pickups. One could truly earn a cape of a wizard if one was to learn every feature and use them in a live set. Good clean tones and repeats are well controlled. This truly isn’t your average delay and i believe the designer has done his/her work by chasing the features that are not found on every single delay unit out there.

Sound good and works fine with suitable power supply. Some of the features still elope me, but that’s just me. You should try one out to see if you like it. For me, i’m a lumberjack.

Boss MZ-2 Digital Metalizer

Sunday, March 8th, 2015

Boss-MZ2

What is it?
Boss MZ-2 Digital Metalizer from Boss Compact series. Made in japan, july 1988.

Now, since i’ve lately been looking at these late 80’s analog/digital hybrids, this may be a decent unit to continue with. We are looking at Boss’ take on the distortion plus delay/chorus effects that were widely available back in the day. DOD had it’s own as “Hard Rock Distortion” and Ibanez shuffled the deck with its Session Man pedals. I’m quite sure there were others trying to take the markets too. There sure was i time and demand for this kind of combination back then. While the competition had the delay and chorus lines done mostly by analog methods, Boss aimed for the moon and made it digital, while leaving the distortion part analog.

Once the bottom plate is removed, my reaction was to freeze for a few seconds. Wow. Part of the traces look like good old japanese hand drawn beauty, but the digital signal processor’s small traces try to keep up with the old school design. Those thin, round traces at the right hand side of the DSP look very pleasing.

Boss-MZ2-guts1

As with other digital Boss pedals of the era, the mixture of through hole components and SMD parts is in place. In addition to having two separate, stacked boards to accommodate everything. While these combo effects do not interest me all that much, i must say i find this unit very appealing.

Boss-MZ2-guts2

What comes to controls, we have our basic three knob layout for the distortion part, including gain/distortion, tone and volume. The digital section has only presets for being off, having couple of different choruses and delays on or off at the same time. Lack of more controls to the digital part feels kind of boring, but the presets are actually quite good. Sadly, i couldn’t find a schematic of the analog board to confirm how the distortion part is made up. I think there may be similarities with other Boss distortions, but there must be something different in there too.

How does it sound?
Very much usable distortion. Kind of like DS-2, but with certain amount of personality thrown in. For the distortion side, this may very well be one rare boss effects with a real personality. They could have offered the distortion part as a separate pedal, but since the modulation/delay can be turned off, it doesn’t matter all that much. For the delay and chorus modes.. Well. If you want the sound of a late 80’s hair metal lead solo for your tapping pleasures, this is the pedal that you really need. It is fun to play around with this. Sure enough, it kicks the living daylights out of the competition.

I’m sort of glad that this type of combination isn’t “in” here in the mid-2010s. This is due to change once someone rediscovers the MZ-2 and manages to make a hit with it…

DiMavery EPDL-50 Delay

Tuesday, February 17th, 2015

DiMavery-EPDL50

What is it?
DiMavery EPDL-50 Delay. Made by Daphon in china around late 00’s or early 10’s.

I was on the hunt for the original Daphon branded E20DL as it’s apparently the same circuit as for Daphon E10AD. The reason for hunting down a low end brand’s delay unit? The schematic for E10AD on Dirk Hendrik’s archives suggest that the design is actually very close to certain Maxon developed analog delays. And since this chinese manufacturer was responsible for producing the plastic Ibanez soundtanks, my interest raised too high to resist getting one. Daphon branded units are pretty scarce here in europe, so i just couldn’t find one. What i did find was a DiMavery branded version of the E20DL from a german retailer. And the price was decent enough too. The shipping cost wasn’t cheap, but that’s mainly due to the unit weighting a ton. Once the parcel arrived, it was time for a test run and to see how the unit was made. First thing that caught my eye was the horrid “quick fix” (TM) on the boards dc jack side. As the number of solder joints shows, there will be a lot of components in there.

DiMavery-EPDL50-guts1

And there are. Most of the board design looks a lot like the ones we see in every Soundtank. So everything’s in order so far. The DDB is modern BL3208, a 2048-step BBD. The noise content for the delay line is tamed with a compander. In all, pretty straightforward analog design in a box that’s way sturdier than most others. Weighting in at about 700 grams, the box is definitely one of the sturdiest of all.

DiMavery-EPDL50-guts2

The enclosure may be great, but. What comes to build quality, i’m not too impressed. Insides are made with cheapest parts available, and while the workmanship beats most Danelectro mini series units, it’s still sub-par when compared to Ibanez Soundtanks. Which is pretty odd, since we are talking about the same factory. Maybe the profit margin for current OEM’d boxes is less than what it was with Ibanez. Either way. This represents the cheapest metal housed analog delay in existence. Sad thing, but low price point doesn’t usually add up to high quality. And. I’m afraid there’s more.

How does it sound?
If we start by playing around with slap back type delay times, set the feedback accordingly and dial the mix to suitable levels. Then, this is very nice effect with smooth and soft analog feel to its tone. I’d estimate the maximum delay time to be something like 300ms. But there’s an issue. If and when the delay time is set above half turn, there is distinct higher frequency distortion present. My guess is that this is due to slightly misbiased BBD. And since the board doesn’t have a trimmer, this can’t be remedied simply with a screwdriver. So as it is, the short delay times work well and sound good. Longer times are next to unusable. I bet this could be modded to work better, but i haven’t found it in me to do so. Maybe some day. On the other hand, the distortion on long times in addition to self-oscillating feedbacks do make this very reasonable and cheap analog delay unit for all you noise heads. Looking for a hifi analog delay? Look somewhere else.

Marshall EH-1 Echohead

Saturday, February 7th, 2015

Marshall-EH1-Echohead

What is it?
Marshall EH-1 Ehcohead delay/echo. Made in china around early 00’s.

My relationship with these effects isn’t anything too special. I just simply like them for their heavy construction and fine tones. Most of the units in this series (which i like to call “small metal series”) are relatively low on their price point and most of the designs are still available as new in 2015. I’ve already been inside a few boxes and may have pointed out that the chinese factory that manufactures these for one of the UK’s coolest brands may be the same shop that is responsible for Ibanez 7-series. At least the board manufacturing methods and and component placing do suggest that. I have absolutely zero evidence to back me up on this. It’s just a gut feeling. As it is a gut feeling to like these units. Well. A small form factor, good tones and box design that will be able to take a hit on a road.

To begin with this delay/echo unit, opening the bottom plate shows a board that reeks of digital design. This was to be expected. There is no way the design could have been analog with the set of features we have on the pedal.

Marshall-EH1-Echohead-guts1

The electronic design itself is rather complex. We have our Texas Instruments DSP chip, plus Atmel and BSI controllers. The motherboard is taking care of the AD/DA conversion and the effect itself, while the switching, buffering and mixing is handled on the second board.

Marshall-EH1-Echohead-guts2

With current, limited understanding of digital design, i have to leave with these photos and a notion that if someone wants to design a digital effect with SMD components, it surely should look something like this. In my opinion, at least.

Marshall-EH1-Echohead-guts3

But what about features? I said above that the amount of features made me think digital in the first place. For the connections, we have mono input  with stereo output and a jack for external momentary tap tempo switch.  In addition to DC jack, of course. The knobs are representing the basic controls required for a delay/echo. Level setting the balance between clean, or dry and processed, or wet signal. Feedback controls the amount of repeats and delay time is pretty self explanatory. And what’s more important, the delay time ranges from nothing to up to 2000ms.  2000 milliseconds in this price range is very, very respectable. Last knob is a switch for the effect type modes. I’ll say a few words about these in a second.

How does it sound?
Well. To begin with, great. Controls are well responding and the six modes offered all sound different. First mode, the HIFI, has its overall tone in Boss DD-7 direction, with still being pleasant and usable. Usually this type of pristine on digital delays ends up in emphasizing the high frequency content resulting in extremely cold and piercing repeats. This one here has great tone, even on HIFI mode. Next two are Analogue and Tape Echo modes. These have similarities, but both of them do a very decent job on modelling the types they represent. Multi-tap is next, and it’s a great feature. The repeats are handled in a different manner than on the previous modes. Sure, the mode doesn’t live up to all its potential since the controls are just basic. Nice addition still. Then we have the Reverse mode. To my ears, this reverse is better than the one we’ll find in Digitech’s Digidelay. Simpy put, usable reverse delay. The lasts mode is Mod Filter. So we do get a modulation delay in the mix too. The modulation, obviously lacking in controls, isn’t the best modulation delay i’ve heard, but still. A very good one.

This set of features with all the different digital delay tones. Usually cheap does not add up to good. This time is does. While the engineers have been forced to drop a few things out, they have still managed to squeeze a respectable amount of features in a such small package. I have very little negative to say about this pedal.

DOD FX96 Echo FX Analog Delay

Sunday, December 28th, 2014

DOD-FX96-EchoFX

What is it?
DOD FX96 Echo FX Analog Delay from FX series. No serial number, but component stamps suggest the unit is made is USA, 1999. The America’s pedal is once again perfect source for the version details and additional info. So check that out before continuing.

I’ve been partly in love with analog BBD-based delay units for a long time. They all do have their shortcomings and added noises, hisses and relative uncontrollability. While the sole idea of using a small chip with thousands of FETs stacked in such a small device is almost stupid, the sounds these chips are able to keep delayed is something that cannot be achieved in any other measures. Many have tried to model an analog delay in modern digital methods, but as many as there are folks trying it, there are equal amounts of people who have failed in this task. In our modern world, the analog delays are not in the cheap. Mostly due to the fact that manufacturing these chips is expensive and are currently produced in limited numbers. Sure there are a few types that are still in production, but not the ones we really want to see and hear in a effects pedal.

Everything about FX96 looks and feels like every other pedal in the series. Quality through hole components and the touch of hand labour is just glowing with pride. This unit houses the revision B circuit board, which adds a 1M trimpot to the original revision.

DOD-FX96-EchoFX-guts

I’m not too interested in the buffer/mixers or even in the SA571 compander (which is used to compress and decompress the signal sent to the delay line and decompress it again afterwards), but the delay line itself. In this model, the bucket brigade device is the almighty MN3005. A 4096-stage BBD and it’s driven by a MN3101 clock driver. In my limited experience with analog delay units, the MN3005 has most definitely been the crown jewel in the list of all BBD chips ever manufactured. Due to its high number of FETs, it can produce up to 800ms of delay time with very reasonable amount of signal distortion (as a side note, the compander is there to eliminate part of the noise and/or distortion produced by the FETs). So long delay times with little distortion. This is the s*it.

The controls are Mix, or Dry/Tape, which sets the output ratio of buffered clean signal and signal processed by the BBD. Delay/Time is used to set the time the signal is stored in the BBD chip before releasing it. This ranges from a few milliseconds to respectable 800 milliseconds. Regen/Repeat sets the amount of signal being passed from the output of the delay line back to its input – resulting in feel of continuous echo. This control ranges from single slap back to infinite “self-oscillating” repeats. I use quotes for “self-oscillating”, since this feature found in most delay effects isn’t exactly an oscillation. And finally the Tape/Quality knob controls the higher treble frequencies that are being passed in the feedback. More cut on the highs and the repeats will die quicker. Not in completely different manner than what we may hear some old tape echo machines to produce. If the high cut is minimal, then the sound will remind us more of a modern digital delay, while still being all analog.

How does it sound?
From rockabilly slapback to super space wars. I said before that this unit is little distortion. This doesn’t mean that there isn’t any, it’s just that the amount of noise/hiss/distortion is at lower level than with some other analog delay units. It isn’t squeeky clean, but the noise floor level on high delay times is just giving it a bit more character, while it doesn’t hurt tone. At least not that much. Very good range in controls, which let you set the the tone to be anything from real vintage sounding to modern. Sure. It does not sound like those pristine modern digital devices, but it sounds very, very good.

If you are after a studio grade noiseless delay, then look elsewhere. But if you are after the tones from the past and beyond, all the way to reality of space, then this unit is for you. I’m nearly in love with it. If i was to sell my collection, this one would be the very last to go. Once i played with this, i was immediately convinced that this is the unit that is a dictionary example of a keeper.

Ibanez DPL10 Digital Pan Delay

Saturday, December 13th, 2014

DPL10

What is it?
Ibanez PDL10 Digital Pan Delay from 10/Power series. Made in japan in late 80’s.

Got this as a defunct unit from one finnish guy i did some deals and trades with. As it was not passing signal, the previous owner had borrowed the stomp lid to another pedal. Gladly, i happened to have one to spare from a defunct (completely dead) DL10 i sourced long ago in a deal of a few pedals that were not in working order. So. To the debugging. The signal died at the input buffer that was a half of 4558 SIP chip. I initially assumed that the chip was dead and it took a while to me to order a few of those in. As those, obviously, are not that common parts to be had lying around (now i do have a few if i ever need them again). As the voltages on that chip pins didn’t look healthy, my assumption was the chip being dead. The rest of the circuit seemed to be in working order, as when i injected the guitar signal to either one of the M50195P digital delay chips, the output was correct. Swapped the 4558 for a new one and nothing. Still the voltages were off by any standards.

DPL10-guts1

And of course there’s no factory schematic around for this unit. So i had to do some detective work to find out what was wrong.  I noticed there was a separate reference voltage network for the input buffer and the measured voltages on that network were off too. In other words, the reference voltage wans’t there. The chip was getting the supply voltage, but the reference. I widened my search for the cause and everything seemed to be in order. But the input buffer still didn’t get its reference voltage.

DPL10-guts2

Went on to check more and more and tested the continuity of a few key spots for this netork. Finally i found it. It’s not that common for the 10-series to have two sided circuit boards. Most of the designs are utilizing a single sided board with other side for solder and other for components. This is not the case with PDL10. And when i think it more, this is not the case for any of the more complex boards, mainly delays, in this series. So i finally found the reason for the defect and what was causing it.

DPL10-guts3

At one point, this unit has gotten a jolt from reverse polarity power supply. Due to burnt out parallel polarity protection, the diode has been replaced after the incident. The person who serviced the pedal soldered a new 1N4007 diode in place and since that didn’t fix the pedal, he must have deemed it totally broken. But no, it wans’t totally broken. The issue was that the cathode side of this polarity protection diode acts also as an via, which connects the supply voltage to the other side of the board too.

DPL10-guts4

And this via is the spot that takes the supply voltage for the voltage divider of the input buffer’s reference voltage network. And since the diode wasn’t soldered properly on the component side, but only on the solder side, the network wasn’t getting its supply voltage. I then reflowed the solder around the diode and boom. Working PDL10.

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Repairing this unit was a great challenge and i’m more than happy that i could do it. This Pan Delay is already enjoying a “rare” status and the prices are what you would expect from a rare mid-80’s Ibanez pedal. The design is pretty cool, but since it is what it is, a hit it was not. Sure. One can use this in a similar manner than the DL10, which has the same digital delay line inside, but in that case, 50% of the effect is unused. Pan delay in this case means that there are two delay lines constantly out of sync with each other. The input signal is splitted to both lines’ input and the outputs are separate. Meaning that the outputs are meant to be used for stereo. This way the other delay line pumps its repeats in one phase to to the left output and the other pumps its repeats, out of sync, to the right output. And this creates our ping-pong style panning delay.

Not that many panning, or ping-pong delays out there. And at least to me, the reason is pretty simple. Most of us use out pedals with guitars. Guitars tend to have one output and amps tend to have one input. So the stereo use is best to leave with studio experiments.

Either way. It is a beautiful unit with crowded board and neat board design. Definitely a one trick pony, but a rare specimen of this particular trick. Amazing unit to have.

How does it sound?
Good. It can be used as a single delay line, and in that scenario it doesn’t differ much from the sleek and smooth hi-fi digital delay tones of the DL10. Actually is sounds exactly the same. I think one could achieve the same sounding effect by splitting a signal for two DL10s and somehow creating a separate sync for those. It is clean and nice sounding delay with nothing too special in its tone. The ping-pong output is the speciality on this one. Great unit for studio work.