Some pics of a recent nonlinear circuit module build.
Its a delay -- for gates .. will help to loosen up my rigid drums.
The CV controlled delay has a huge range..... from 7 milli-seconds to 1 minute.
You can get longer times by replacing the 1uF caps with larger values, say 10uF
This module is in Eurorack format.
gET the SMD stuff on first.
RL = 10k
José Luis Torrente is a fictional character created by Spanish actor and director Santiago Segura and the main character in the Torrente scatological and dark comedy-action film series.
The 808 groove sampler came out in 1998 ... it's 21 years old.
There is a whopping 100MB of memory on a zip drive.
{;-)
The SP 808 shares the same digits are its illustrious brother the famous TR 808 drum.
This however was marketed as a workstation
You can still pick these up on Ebay quite cheaply.. if you are into vintage gear, this is still a good buy.
I think the machine is very underrated and I really like how it sounds.
It's a phrase sampler, sequencer, synthesizer, hard disk multitrack recorder with lots of studio quality effects. I think the market were DJ remixers ... musicians who wanted to sample.
In 1988, computers were basic and computer based sampling really difficult and expensive.
Plus, there is nothing like a real hardware machine that hardly ever crashes.
Daft Punk and The Prodigy used this on stage back in the 1990s
The 16 pads reminded everyone of the AKAI MPC
The Sampler is 44.1kHz and 32kHz. It can hold up to 1,024 samples.
This is spread over16 pads x 64 banks.
Max sampling time is 25mins (stereo) at 44.1.
32 mins at 32khz
Roland used zip disks to store the samples. ... this is one of its weaknesses .......the zip can break down and be hard to repair. sadly WAV and AIFF formats aren't supported.
The D-beam controller -- ITS A BIT LIKE A tHERMIN,
Just wave your hands above it.
You can tweak effects, pitch and volume
tHIS is the zip drive
Back in the 1990s, 100MB was a big deal.
Only SCSI drives could compete with this.
The drive is both a blessing and a curse.
Over time , these break down, Its the Achillies heel.
mIDI IN /OUT / THRU
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For more info on the history of Roland Drum Machines click here
I've tried to rank them on historical importance, engineering quality, accuracy potential, reliability, serviceability, innovation and influence—not simply price or prestige.
One caveat: this is a ranking of movement families/calibres, so closely related generations are sometimes grouped.
Let me know if you disagree ?
............................
Rank
Movement
Era
Why it makes the list
My rating
1
Rolex 3135
1988–2020s
Perhaps the definitive modern automatic: incredibly robust, accurate, proven
Jaipur.
It's a beautiful city with wide boulevards. It's the capital of the state of Rajasthan.
Founded in 1727 by Jai Singh II., it was designed during the British Colonial Period.
It's also one of UNESCO's world heritage sites.
It's often know as the Pink City because it was pained that colour to welcome Albert, Prince of Wales in 1876. Albert, later was crowned King Edward VII. One of his many titles was Emperor Of India.
There are lots of attractions to see when visiting Jaipur.
It's also a good base to visit other parts of Rajasthan such as Jodhpur (348 km), Jaisalmer (571 km), Udaipur (421 km)
A must see when visiting is the Hawa Mahal
This is the front. It's constructed of red and pink sandstone.
There are 5 stories. to this pyramid structure.
Built in 1799 by Maharaja Sawai Pratap Singh, the grandson of Maharaja Sawai Jai Singh, who was the founder of Jaipur
Its been described as a behive. There are 953 windows (Jharokhas). Notice the fine latticework..
Royal ladies were not allowed to be seen by the public without face coverings. This latticework allowed them to view the street, and not be seen.
It's a great sampler ... reminds me of the Roland SP 404 or a AKAI MPC
I've been searching for the best midi sequencer to pair with this module.
I've had success with the Arturia Beatstep Pro (the drum sequencer section) and the Roland TR-8
Midi note numbers output from the tr 8.
The Roland TR-8 outputs midi from channel 10. The midi note numbers are as follows:
Bass Drum - 36
Snare Drum - 38
Low Tom - 43
Mid Tom - 47
High Tom - 50
Rim Shot - 37
Hand Clap - 39
Closed HiHat - 42
Open HiHat - 46
Crash Cymbal - 49
Ride Cymbal - 51
Luckily, the bitbox also responds to midi on channel 10.
Midi input can also be used to modulate some parameters in the bitbox.
Ive seen the cirklon sequencer also used very effectively on the 1010.
Let me know if you of any other sequencers that pair well with the bitbox
note
TRS MIDI B
Arturia (e.g. Beatstep Pro and Keystep) and Novation (e.g. Circuit and
Launchpad Pro) , Music1010 (MX4, blackbox, bitbox, synthbox) use ‘TRS MIDI B
When building a synthesizer power supply, there are two choices:
1. Regulated Linear Power supply
2. Switch Mode Power Supply (SMPS)
----------------------
1. Regulated Linear Power supply.
These are quite simple in design.
Low noise ... most supply types produce no high-frequency interference.
But they are inefficient when compared to a SMPS . Output voltage is regulated by dissipating excess power as heat resulting in a typical efficiency of 30–40%.
Often uses heavy line-frequency transformers
It's hard to find AC Linear Wall Warts larger than 2A. This is a problem if you are building a large modular.
This is a NLC linear power supply. It's very easy to build.
aND ANOTHER example of a DIY linear PSU. One advantage is their ease to build. The components are cheap.
I use a 2A AC brick with both of these.
Something like this:
I find that powering 3U to 6U (max) of Eurorack is OK with these ... check your modules power requirements of course.
You could of course use something like this if you needed more juice:
This is a power one HCC 15-3A
This transformer based design has a center tap to give the centre ground. Both voltage outs are rectified and regulated to create dual voltage
rails
Its very very heavy and would be hard to fit into a eurorack case. I used this in a Serge case.
Above is a doepfer A-100PSU2
Its a Linear PSU with ring core transformer
Output voltages/currents: +12V DC/1200mA, -12V DC/1200mA
Input voltage: 230V AC or 115V AC
Below is the L1 linear PSU
It's a great kit. 1.5A per rail. 5V regulator on busboards.
2. Switch Mode Power Supply (SMPS)
These first came out in the 1970s They are very efficient and their performance is much higher than linear regulators. SMPSs use PWM (pulse with modulation) to regulate the output voltage.
Their efficiency is very high, but the process is extremely complicated & creates high frequency noise.
They use diodes & capacitors to produce high voltage DC. This high DC voltage is then decreased and converted into a steady DC output using a system of transistors, capacitors, diodes, inductors & ferrite transformers.
The power bricks (wall warts) are a modern example of SMPSs. You will find them powering computer laptops and mobile phones.
This is a ATX SMPS from a desktop computer.
The advantages of this type of regulated PSU are that its smaller. There is very little heat generated.
Noisier due to the switching frequency of the SMPS. An unfiltered output
may cause glitches in digital circuits or noise in audio circuits.
Above is the Doepfer A-100SSB. Its a small switcher PSU, suitable for up to 8 modules. (380mA)
Below is the Doepfer A-100PSU3
It's a +/-15V switching supply (wide range input 100...240V for mains voltage) followed by
a linear regulation circuit that generates +12V and -12V. The +5V is a pure switching
supply without linear regulation.
Really interesting design as it combines both linear & switching supplies. The black boxes are Meanwell switching supplies. They create +15v, -15v, and +5v. The +/-15V must be passed through linear regulators to get +/-12V. I can't see the regulators in the photo ...maybe they are under the heat sink fins ???
The transformer in a switching power supply is also smaller than a
traditional line frequency (50Hz or 60Hz depending on region)
transformer,
If you need a high current wall wart a SMPS PSU will be easier to find. I use a 10A brick to power one of my Buchla cases.(though the OEM brick is expensive).
A great switching PSU which seems ideal for a small eurorack case (around 200HP)
5 VDC(5A)
12 VDC (2.8A)
- 12 VDC (0.5A)
You can use a Bus board with filtering to remove the PSU ripple noise.
Use something like a LC filter.
This consists of an inductor ( represented by the letter L)
connected in series with the power flow and a capacitor (represented by the letter C) from the filtered voltage
to ground.
I guess before you do this you need to ask the questions;
Are you better off filtering the noise, or preventing noise in the first place?
Is there actually much noise ?
Is the LC filter making more noise than it is removing?
------------------------------------------------------------------------------------------------
Below is another example of a switching PSU
Its a Meanwell PD2515
Mouser: 709-PD2515
It supplies : 24W 15V/0.8A -15V/0.8A
iTS ok FOR a small buchla system
-----------------------------
Finally, this is the PSU for my amalgamod Eurorack system:
WAM Active Limited (ASX: WAA) operates as a Listed Investment Company (LIC), meaning its financial metrics look very different from a standard operating business. [1, 2]
Because it functions as an investment fund, its "profit" is entirely dependent on market cycles, and it traditionally carries 0% debt. [1, 2]
Over the last 10 years, WAA has maintained solid consistency, punctuated by an absolute record-breaking year in FY2026 driven by heavily concentrated bets in small-cap resources, critical minerals, and artificial intelligence
....................
📊 Financial Breakdown Over the Decades
1. Profit & Investment Income
The Trend: WAA’s net profit fluctuates significantly from year to year because it relies on the realized and unrealized gains of its stock portfolio. Historically, it captures modest single-digit millions in quieter market years (e.g., $5.8M in FY23, $7.4M in FY24). []
Recent Performance: The company recorded its strongest financial year since its 2008 inception in FY2026. Driven by an astronomical portfolio return of 75.5%, operating profit before tax surged 360% to $48.1M AUD, while operating profit after tax grew to $33.8M AUD. [1]
2. Debt Levels
The Trend: WAA has consistently maintained 0% debt/equity leverage.
Why it matters: As an LIC focused on an active trading style with small-cap equities, it manages liquidity entirely through cash reserves rather than debt. During volatile patches in 2026, its cash holdings peaked at 35.5% to mitigate risk and maintain buying power. [1, 2, 3]
3. Return on Equity (ROE) & Management Effectiveness
The Trend: ROE generally hovers between 9% to 13% during normal market conditions (e.g., 9.1% in FY23, 10.4% in FY25).
Recent Performance: Trailing Twelve Month (TTM) figures place its Return on Equity at 17.29%, driven by the aggressive tailwinds of its underlying portfolio allocations. [1, 3]
4. Dividends & Capital Management
The Trend: Providing a regular income stream via fully franked dividends is a core objective. WAA has a 10+ year track record of paying robust, fully franked dividends. [1]
Recent Performance: Capitalizing on the FY26 windfalls, the board distributed a total of 9.4 cents per share (6.4¢ full-year dividend + 3.0¢ in special dividends), offering a grossed-up dividend yield of roughly 12.7%. [1]
⚠️ The Catch: The Share Price vs. NTA Discount
When looking at WAA's 10-year trajectory, a crucial metric for investors is the relationship between its share price and its Net Tangible Assets (NTA). [1, 2]
Even though its underlying portfolio grew at an annualized rate of 13.3% since inception, the Total Shareholder Return (TSR) over the past 5 to 10 years has slightly lagged behind the actual portfolio performance. For instance, while its 5-year portfolio return to mid-2026 was a massive 20.6% p.a., the actual shareholder return was 9.6% p.a. [1, 2]
This lag is due to WAA shifting from trading at a 7.5% premium to NTA back in 2021 to trading at a persistent 9.5% discount to NTA. The stock market has historically undervalued its explosive asset gains, creating an environment where investors can currently buy the underlying assets at a discount
.................
The Net Tangible Assets (NTA) per share for WAM Active Limited (ASX: WAA) typically fluctuates around $0.90 to $1.15 before tax over a rolling 10-year period. [1, 2]
Because WAA operates as an active trading Listed Investment Company (LIC) that distributes a significant portion of its profits as regular fully franked dividends, its NTA does not show a linear capital growth curve. Instead, gains are continuously recycled and paid out to shareholders. [1]
📊 Long-Term NTA Trend Overview
While month-to-month figures move dynamically with market conditions, historical snapshots outline how the pre-tax NTA generally moves:
Recent NTA (Mid-2026):$0.96 (as of July 31, 2026), recovering strongly after an exceptional year where the investment portfolio grew by 75.5%.
Early 2026:$1.02 (February 2026).
Mid-2021:$1.00 to $1.03.
Historical Base (approx. 10 years ago):$1.01 (September 2015). [1, 2, 3, 4]
💡 Key Contextual Mechanics
When evaluating WAA's NTA history over a decade, it is crucial to account for two main wealth-degrading impacts on the asset value itself, which are instead passed to investors as total return:
Dividend Decretion: WAA has distributed over 108.9 cents per share in fully franked dividends since its inception. Because paying a dividend directly lowers the company's cash balance, each dividend payout permanently clips the NTA down by that exact cash amount. [1, 2, 3]
Performance Fees & Tax: In high-performance periods (such as FY2026), sizable corporate tax obligations and performance fees create a variance between gross investment portfolio returns and the ultimate net tangible assets reported to the market. For example, in FY2026, the portfolio returned 75.5%, but performance fees and tax narrowed the pre-tax NTA increase to 51.7%. [1]
