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PEQ-503 EQ - 500 Series Equalizer

2010-11-19T12:00:52.0770000-06:00

Back in July, I showed you how to design an Eagle CAD Library for a switch. After a month or so, I've released a new product. My PEQ-503 EQ, which incorporated this switch library I designed.

Here are some photos:

The FiveFish Studios PEQ-503 is a beautiful, high-quality, single-channel three (3) band Inductor-based equalizer, designed for the popular API VPR500 Rack format.

Each frequency band has two (2) selectable frequencies, and a bypass switch. It also has an overall EQ In/Bypass switch to let you easily make sound comparisons.

The equalizer's smooth broad curves makes tonal adjustments easy and fast. You can go from small, subtle changes to extreme carving or boosting up to +/- 18dB per band. The SUB and AIR frequency bands can give your tracks the chest-thumping punch you want, and that extra sparkle at the top end without sounding harsh. The mid frequencies band takes care of adding that extra bite to your sound to make it pop.

The PEQ-503 Equalizer uses the following:

A balanced line level receiver using InGenius® high-common mode rejection technology.
An ultra-low distortion, low noise, operational amplifier optimized for high performance audio is used in the EQ section, along with imported Carnhill inductors from the UK, to perform the musical tone shaping and sculpting of your sound.
Using OutSmarts technology for the Balanced output driver, thus capable of driving difficult loads, with short-circuit protection.

The PEQ-503 is all about choices. You can outfit the EQ with optional Discrete 2520/990 type op amp*, and an Output Transformer*. You can also request special panels colors*, just email us for availability. There are also on-board jumpers on the EQ that allows you to experiment and change the Low Frequency and Mid Frequency bands from the factory default setting, to better suit your taste or musical style. Output Bypass jumpers also allow you to change between an active balanced direct output, or transformer output coupling.

Join the other professionals that have discovered the PEQ-503 Equalizer's quality performance. The PEQ-503 is equally at home for use in the mix bus, or individual tracks and channels. You will love it!

* Available separately, extra charges may apply.

FiveFish Studios and the PEQ-503 Equalizer is part of the API VPR Alliance.

The VPR Alliance is a program of standardization and consistency guidelines set by API Audio for manufacturers, to make our products physically fit and electronically conform to API's 500 series rack specifications. As stated on API's website, "Customers benefit from the VPR Alliance through the elimination of any confusion as to which products are endorsed for placement in API racks. Customers also benefit from a wider range of module choices for their racks, safety in the knowledge that the specification of the third party unit is correct, and that there is no risk of damage occurring. "

PEQ-503 Features:

3-Band EQ - Inductor Based EQ
Two Frequency Selection switch per band + independent flat/bypass position
12K/AIR HF control +/- 18dB gain
1.1K/3.2K MF control +/- 18dB gain
SUB/120Hz LF control +/- 18dB gain
EQ On/Bypass switch
Relay-controlled Bypass
Electronically Balanced Inputs using inGenius Technology
Electronically Balanced Outputs using OutSmarts Technology
Output Tranformer option
Discrete OpAmp option, or PDIP chip
Using Carnhill/UK VTB inductors for LF and MF control
WIMA caps for EQ filters
1% metal resistors
Bourns Potentiometers
Solid Machined Aluminum Knobs
CNC-milled/engraved/paint-filled front panel
Double-sided, plated through PCBs
Low Noise Equalizer
Jumper settings for experimentation, changing the EQ filter frequencies

You can buy this EQ using this link.
http://fivefishstudios.com/500-series-modules/peq-503-equalizer

This Is My Workflow When Designing A New Eagle Part Library I Like To Buy The Part Before

2010-07-28T14:59:14.8585000-05:00

This is my workflow when designing a new Eagle part library.

I like to buy the part beforehand, if possible. This gives me the chance to touch it and visually inspect the part and verify that the part dimensions match the working drawings from the manufacturer.

If working drawings from the manufacturer are not available, I use my digital caliper to make detailed dimensions of the part outline, and pin spacing and pin diameters.

If official PDF working drawings/datasheet are available, I use it though. Trust, but Verify.

Today, we're creating an Eagle part library for a switch.

Opening the datasheet, we look for the part dimensions.

In this case, we also take note of the switch positions, to see which terminals are connected depending on the switch position (up or down).

Next step is creating the schematic symbol for the part. In this case, an SPDT switch.

We also add "pins" to the schematic symbol. I use a "point" when defining pins on the schematic symbol.

I also like to match the "pin numbers" with the actual pin numbers used by the manufacturer.... makes life simpler.

Next, is creating the physical outline of the part. This is the FUN part for me. I like to make the part looking as authentic as possible. We also take care that we're following the part dimensions specified by the manufacturer. Don't forget to check pin spacings, and most importantly... pin DIAMETER. Since the PCBs will have plated through holes, I make the pad diameters just a hair-thin slightly bigger.

To make working easier, make sure to set your snaps and grid to 0.05" square, and 0.01" for the fine grid spacing.

And make sure holes/pads are centered on each "snap."

Make a print out your part and overlay the real part against your "printed part outline." Check if the holes, dimensions are correct and aligned. You may need several passes to get this right if you don't have official working drawings and just relying on caliper measurements.

If everything looks good, then we proceed to the next step.

Now, we tie together (match) the pin#s we created in the schematic symbol with the actual pin#s in the part outline.

This is also a good time to enter a part description field. I try to include Mouser or Digikey part #s in the description.

Next step is I try to use the new part library in a test schematic.

I want to verify that when I connect other components to this new part, that the correct pins correspond with the PCB design.

This is a good time to catch any errors you've made in pin-matching.

Here's our test schematic. R1 is connected to terminal #1 of the switch, R2 connected to terminal #2 and R3 connected to terminal #3.

Then we switch to the Board Layout view and verify that it's correct.

And we see that everything is OK. The pin #s in the schematic match the pin#s in the board layout.

In Eagle, the text ">NAME" and ">VALUE" are special. Eagle will substitute these text with the actual part name and part value in your schematic.

So in the symbol editor, let's add these text. Put the ">NAME" in the NAMES layer and put ">VALUE" in the VALUES layer.

In the Device Editor, click the Prefix button. Enter a prefix text.

Since this is a switch, we could use the prefix "SW" or "S". Now when you add multiple parts in your schematic, it will be renamed "SW1", "SW2", "SW3".... (Of course, you need to have ">NAME" present in the symbol, see step above.)

And we're done.

MX5 Mic Preamp - FiveFish Studios - API 500 Series Lunchbox Preamp

2010-06-01T14:37:17.3580000-05:00

MX5-mk500 Mic Preamp

Meet the newest member of the FiveFish Studios line of 500-Series preamps... the MX5 mk500 Mic Preamp.

Just like it's brother, the X-72mk500, the MX5 Mic Preamp features the same UK-made Carnhill Input Transformer to deliver that big, punchy, lots of low end mojo sound.

A custom made output transformer takes care of balancing the beefy outputs, and also adding it's own sonic signature.

Mil-spec Grayhill 12-stepped gain switch, and a separate Output Trim knob gives you fine control over this preamp. Lighted push-button switches gives a visual indicator for the status of your 48V phantom power, -20db Pad and Polarity Reverse switches.

Custom-made, solid machined aluminum knobs gives the MX5 preamp an expensive look. But don't let it's features and expensive looks fool you, the MX5 is priced very attractively to fit the budget of every home, project or recording studio while still delivering on performance and features!

You also have the option to use Discrete Op Amps (DOA) like 2520/990 type opamp with the MX5 preamp. Just swap out the stock chip, with a Discrete OpAmp for a slightly different flavor.

Photo showing the MX5 preamp along with our SC-1mk500, X-12mk500 and X-72mk500 Mic Preamps.

The MX5 sound is BIG, PUNCHY, and HUGE. It adds a deep, nice, WARM coloration to the sound. Really deep-sounding huge. And low frequencies come out punchy and TIGHT... thanks to the UK-made Carnhill Input Transformers.

The custom output transformer also gives the preamp a slight mid-forward, smooth sound character. A very fast video buffer driver chips (spec'd at 2000V/usec) drive this custom Output Transformer.

You can say the MX5 is a hybrid of our X-12 and X-72 preamp. The MX5 exhibits qualities that can be found on both preamps - I'm sure you will love this new preamp!

MSRP: $625 (with Carnhill/UK Input and Custom-made Output Transformer)

Using UK-made Carnhill Input Transformer
Custom Output Transformer
12-step Gain from 22dB to 68dB, at 4dB/step
-20dB Input Pad
High-quality parts
Option to use Discrete OpAmps with the 990/2520 format
Using high-performance chipsets, currently the best chip around
Using High-speed 2000V/us, video buffer, high-current transformer line driver
Using Grayhill switch - high quality mil-spec
with output trim Bourns potentiometer - so you can overdrive the input trafo and be able to trim the output of the pre.
Null offset trimmer adjustment
LED-lighted push buttons for 48V phantom, pads, and polarity reverse
Relay Controlled Polarity Reverse
Relay Controlled -20dB Pad
Soft-start/Ramp-up 48V Phantom Power
Includes on-board voltage regulators
Professional PCB, Rohs PCB with double-sided, plated-through holes, 2oz. copper
with soldermask, silkscreen layout,
Includes everything... 5-LED VU Meter, spacers, screws, knobs

NOTE: The MX5-mk500 Preamp requires an API 500 Series Rack or compatible rack.

You can also use discrete opamps with these preamps.
Discrete OpAmps not provided with preamps.

MX5-mk500 Mic Preamp (INTRODUCTORY OFFER)

For USA Buyers

For INTL Buyers

$495 - MX5-mk500 Mic Preamp

IT'S BACK!!! My FIVEFISH STUDIOS CRAZY DEAL SALE again... !!!

2010-02-01T14:11:17.0463750-06:00

IT'S BACK!!! My FIVEFISH STUDIOS CRAZY DEAL SALE again... !!!

LIMITED QUANTITY OFFER! I have designated a certain number of units for this SALE. LIMITED QUANTITIES AVAILABLE. If my stock runs out in 5 days, or 2 days, that's it. The SALE will be discontinued.

SAVE MONEY!!! $300 for a pre-assembled X-12mk500 preamp.... $300 ready-made (not a kit). Hurry and don't miss out again on this offer!

Please allow 3-4 weeks for delivery. We're still waiting for the trafo shipment from the factory. LIMITED QUANTITIES AVAILABLE for this sale. Sale may be discontinued at any time once stock runs out.

Link and BUY button on this page... http://www.fivefishstudios.com

Low Wattage Guitar Amplifier Kits

2010-01-04T11:02:59.2810000-06:00

Featured above are working builds of the 8 Watt Ardmore and 1/2 Watt Gilmore Jr Kits designed by Gerhart Amplification tone wizard, Gary Gerhart. Everything is included except solder (use 60/40 rosin core solder, no flux). The chassis are finished for the Customer with all holes being drilled and punched. Note the stainless steel PEM nuts press fitted into the chassis for a solid, quality build. Kits feature a Mil-Std black anodize chassis, Mercury Magnetics power transformers, Gerhart Amplification's proprietary output transformers manufactured by Mercury Magnetics and all stainless steel chassis hardware. The assembly manual guides the builder through each step. The Gilmore Jr or Ardmore Kit are an excellent choice for those who are building for the first time, yet challenging enough for those who have built kits before. Guytronix stands poised and ready to assist the builder throughout the assembly process.

Click here for more details. http://www.guytronix.com/

Miniature Vacuum Tube Preamplifier

2010-01-03T16:35:23.0930000-06:00

Look at this... A low cost tube preamplifier using two low power consumption Raytheon JAN6418 sub-miniature pentodes. Kit is supplied with PCB and on-board components. Made by Oatley Electronics.com

Push-Pull Vacuum Tube Amplifier

2010-01-02T16:31:27.0460000-06:00

This 6V6 amp was built following the push-pull (PP) EL84 / 6V6 Dynaco A-410 output transformer schematic. There are a few minor deviations from the original schematics. Instead of Dynaco transformers, Hammond 1608A audio output transformers and a Hammond 272HX power transformer were used. The EL84 / 6V6 PP Dynaco A-410 output transformer schematic showed a 1000 ohm feedback resistor which resulted in bad amplifier oscillation. Feedback resistor Values between about 6 and 10 k-ohm worked well and I settled on 10k. A 5Y3 rectifier would have been to small for a stereo amp so a JJ GZ34 rectifier was used. It became necessary to put a 100 ohm resistor before the first power supply capacitor to bring down the B+ to about 325 volts as I was getting in excess of 345 volts (there is less voltage drop through a GZ34 versus a 5Y3).

Click here for project details. http://diyaudioprojects.com/Schematics/DIY-Push-Pull-PP-6V6-Tube-Amplifier/

TS-2 Rev.B Preamp Redesign

2009-12-28T17:04:46.5937500-06:00

A flash of inspiration... I found a smaller footprint output transformer I can use... so I created an Eagle part library for that. (Tip: use a digital caliper when creating part libraries)

After some creative rearranging of parts, and I made this.

This is just the motherboard. Measuring about 6" x 6".

Ch-check it out!

2 Input Transformers - NEW FEATURE
2 Output Transformers - NEW FEATURE
Gain and Trim knob for each channel
2 VU Meters
4 Full size XLRs
Relay Controlled switching - NEW FEATURE
Bigger DC Converters - NEW FEATURE
... and better PCB layout by re-arranging parts.

Also, reduced the number of molex connectors from the original (7) to a single 10-pin Molex! That will be a big time-saver.... plus the use of PCB mounted XLR Neutrik Jacks.

Sound Card Interface / AC RMS voltmeter Kit

2009-12-23T21:19:43.5460000-06:00

This looks like a very interesting project. If you're into audio measurements, this project might also interest you.

From the Pmillett website...

Most of us DIY audio types have been using PC sound cards to make measurements. There are excellent, inexpensive programs available to do test and measurement of audio equipment available. Personally I use Audiotester. If you've been around my web site you've seen FFT plots generated that way.

What has always been lacking is a decent interface between the sound card and the device under test (DUT for you geeks). There has been much discussion in forums like DIYaudio about this, and many proposals and circuits shown, but so far I've not seen anything implemented.

The problem with sound cards is that they are designed for fixed line-level inputs and outputs. Depending on the card this may be between 1V and 5V RMS maximum. They are also not tolerant of overloads - accidentally deliver 20V into your sound card input and you will most likely be looking for a new sounds card.

http://www.pmillett.com/ATEST.htm

Vacuum Tube Amp Kit

2009-12-22T11:37:06.2180000-06:00

DIY'ers today have it good! There's lots of projects available on the net to build. Here's a Tube Amp Kit by OddWatt Audi.

The manufacturers specifications for the kit are as follows:

Rated Power Output: 25 watts (RMS)
Input Sensitivity: 1.5V (at rated power)
Input Impedance 100 k-ohm
Input Terminal: Line Level RCA
Speaker Output Taps: 4 and 8 ohms
Distortion: less than 0.5% through half power, 1% at full power
Frequency Response: 8Hz to 20 kHz +0/-1db at any rated power
Signal to Noise Ratio: less than 80dB
Tubes: Gold Lion KT88, NOS JAN Philips 5751
Supply Voltage: 120VAC 50/60Hz
Power Consumption: 130 watts (each monoblock)
Weight: 6.3 kg (each monoblock amp)
Dimensions: 205 mm (W) X 225 mm (H) X 300 mm (D

http://diyaudioprojects.com/Tubes/5751-KT88-Tube-Amp-Kit/