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Thursday, October 3, 2013

Watch BigDWiz interview Mark @ CarAudioFabrication!

BigDWiz Interviews Mark at CarAudioFabrication

Check out this detailed interview of the man behind CarAudioFabrication!

The video is over an hour and a half chocked full of interesting content and insight behind the man who tells the "secrets" of car audio. Be sure to check the information below the embedded video...you'll be able to jump to a specific question in the interview. I wish everyone would, but doubt most people will watch the entire 1 hr and 38 minute interview, so to make it easier, I added links to the exact point of the video for each question I asked Mark.

We discuss everything from where to buy fiberglass material to what we think about Steve Meade's success! I had a great time interviewing Mark and think you guys will enjoy watching the archive.

Check out Mark's Website:
http://www.caraudiofabrication.com
And the Car Audio Fabrication YouTube Channel
http://www.youtube.com/CarAudioFabrication

Watch the entire 1 hour and 38 minute video on YouTube
or embedded below:
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Sunday, May 13, 2012

OldSchoolStereo.com Updates - May 2012

Thanks to everyone who visits the website, leaves comments, sends emails and subscribes to my YouTube Channel! The past several months have been extremely busy in my personal life and I haven't had the time to dedicate to the website. I hope you understand this is still a passion of mine, just had to take the back burner for a while. I'm hoping to be back in full force in the upcoming months and have TONS of planned videos, demos, tutorials and other goodies. In the meantime, anyone who has pictures of old school installs (they have taken or have rights to) or do any videos on old school car audio, please let me know and I'll be glad to link to them from here. You can reach me at oldschoolstereo (at] gmail dot com. It may take me a few days to get back with you, so please be patient.

As many of you know, I've been talking about the 1990's 25x2 cheater amps for almost a year now. Well, I recently came across two new additions for the shootout and will hopefully have time to test them soon. I actually have an unboxing video and will post below for one of the amps...MTX Thunder 225 HO. It is rated at 25x2 at 4ohms, but has 90A, yes 90A worth of fusing!!! The epitome of cheater amp status! It may be the amp to beat in the group, we'll see...

MTX Thunder 2300 (left) and MTX Thunder 225 HO (right)

See the video of me unboxing the MTX Thunder 225 HO and comparing it physically to the earlier generation Thunder 2300:

I also recently found a really neat Rockford Fosgate LED sign for the OldSchoolStereo labs. You can see it in the background of the MTX amps above, but also below in an unboxing video:

Thanks as always for visiting OldSchoolStereo.com and please bookmark this page and sign up on the right side of the page for email alerts when a new article is posted. I look forward to your participation in the forums and keep it Old School!

-BigD

Sunday, February 19, 2012

Old School Polk Audio C4 Subwoofer - Fourth Order Bandpass Enclosure

Polk Audio C4 Subwoofer - Fourth Order Bandpass Enclosure with Four 6x9 Subwoofers in Isobaric Configuration

Wow, a true survivor here! An early 90's Polk Audio C4 subwoofer. This enclosure is one of the most unique factory car audio subwoofers of all time. It uses four 6x9 subwoofers mounted in a compound isobaric configuration. The center chamber is sealed, while both outer chambers are vented with a 3" x 5" port. Dual binding posts offer either 4 ohm stereo, 8 ohm mono or 2 ohm mono configuration.

Here are the technical specs provided by Polk:

Driver complement - Four 6x9 drivers monted in a isobaric push pull configuration
Enclosure type - 4th order bandpass
Frequency response - 25 to 150 Hertz
Sensitivity - 94 db @ 1 Watt @ 1 Meter
Recommended amplification - 25 to 200 Watts per channel
Impedance - 4 Ohm stereo, 2 or 8 Ohm mono
Dimensions - 8" H x 26.25" W x 17.125 D
Weight - 26 pounds

Bottom Panel of C4 Removed

Now, looking cool is nice, but sound quality and bass output is what's really important. After reviewing some of the magazines in the OldSchoolStereo library, I found a test of this subwoofer by Car Stereo Review (March/April 1992). Since I don't have the equipment to compile technical measurements of speakers, I was intrigued to see the reviewer was able to get 119dB out of this unit. I've been using a JL Audio 12w6v2 for the past few weeks and although I haven't had my system measured, I feel pretty confident I'm pushing 125dB with only 300w. I guess what I'm alluding to is right off the bat, I wasn't expecting to obtain the output I'd become accustomed to over the past few weeks. However, I have been using a single Kicker Solobaric s10c the past year or so and it has been sufficient for my tastes so the C4 may be enough for my needs.

Now, I've only tested out the C4 for an hour or so total, so I won't leave my final impression until I've been able to give it a few weeks in my car. For now, I'll just say my initial impression is the C4 is quite impressive. It won't flex your windows or take your breathe away, but it will provide clean, hard-hitting, dynamic bass good enough for those looking to add some low end to their modest systems. I'll update the article in a few weeks with my overall impression. I've posted the video overview including demo below. Enjoy!

Make sure to Subscribe to my YouTube Channel to stay updated of my latest videos. You can also follow me on Twitter @oldschoolstereo.

See the video on YouTube in 1080p HD or embedded below:

Thursday, February 16, 2012

Old School Car Audio Bookshelf Speakers? DIY Audiophile Project

Custom Rockford Fosgate AUDIOphile Bookshelf Speakers

Ok, I admit it....I'm an old school car audio junkie! Much of my equipment is in mint condition and actually using this gear is really cool. You guys may recall my Rockford Fosgate AUDIOphile RFA-414 component system from the Old School Boombox article. I was going to need the 4" mids in enclosures anyway, so why not use some small bookshelf cabinets? Exactly! I just needed some patience, a few tools and wallah...my first set of car audio based bookshelf speakers.

The donor bookshelf speaker cabinets were taken from an early 90's surround sound system by a company called Universal. The particular cabinets I used for this project had a 4" speaker, but no tweeter. No problem. A quick trip to the hardware store to get a 2 1/8" hole saw (per Rockford's RFA manual) and the mounting hole for the tweeter was done. It is interesting Rockford recommends a 2 1/8" hole as I found it slightly large....oh well, I digress.

In addition to cutting holes for the tweeters, I also had to line the interior of the cabinets with sound deadening material. The metal enclosures without the dampening material would cause some unwanted coloration (is that a word?). Anyway, I think you know what I mean. After adding the deadening material, the enclosures had a "thud" instead of a "ting". Still not as dead sounding an MDF based enclosure, but much lighter and smaller.

As with many inexpensive speakers, the donor Universal's had tiny 22ga internal speaker wire. This was easily remedied by de-soldering the factory wire and upgrading to some 16ga Phoenix Gold OFC speaker wire. I also used hook and loop tape to mount the AUDIOphile crossovers. The flush mount tweeter pods were mounted using silicon sealant and some custom brackets. Everything came together very well and I'm happy with the results.

Now, I can write all day about the process, how they sound, etc., but if a picture is worth 1000 words, then a video is worth 10,000. I created a video build log of this project and also give a sound demo of the speakers. They are very transparent, but as expected, somewhat weak on the bass output. This component system was designed to be used with a subwoofer and maybe even a midbass. My plans are to cross them over at 150Hz and other plans TBD...

Make sure to Subscribe to my YouTube Channel to stay updated of my latest videos. You can also follow me on Twitter @oldschoolstereo.

See the video on YouTube in 1080p HD or embedded below:

Sunday, January 1, 2012

Alpine 7288 Cassette Radio/CD Changer Controller - Vintage, Old School!

Alpine 7288 Cassette Radio / CD Changer Controller - Pull Out, same Era as 7909

Take a journey back to 1989 with this Alpine 7288 Cassette Radio / CD Changer Controller with Pull Out functionality for security. This was not Alpine's top of the line unit, but at $500US MSRP, it was still a very pricey tape deck. The 7289 was Alpine's most expensive Cassette Radio at the time, $550 (with internal amplification), while the 7390 was the top end Cassette Tuner (no built-in amp) and would set you back a mere $600US. These high-end Alpine head units could control the 5952 and 5959 CD Changers.

So, why would one pay $500 for a Cassette Radio when the Alpine 7904 CD Tuner could be obtained for the same price? Well, you must recall, at the time (1989/1990), most people had cassette collections, but only a few CD's. Alpine was betting most people would opt for a nice cassette radio up front, then add a CD Changer when the funds became available. The 5952 CD Changer was a mere $650, so adding one was a big purchase for most folks. Now, if you had mad cash, you could just trash your cassettes, buy an Alpine 7909 CD Tuner for $1200, then add a 5952 CD Changer for many hours of listening pleasure!

Ok, sorry, back to reality. We are talking about the 7288 Cassette Radio, so I'll try to stay on topic. Let's see some of the technical specifications of the 7288:

MSRP: $500US
Pull-Out for security
4 RCA Pre-Amp Outputs for adding external amplifiers
16W + 16W Built-in amplifier
GR Full Lock Tape Mechanism
Auto Reverse
Tape Frequency Response: 20Hz-20kHz
Dolby B Noise Reduction
CD Changer Controller
12FM and 6AM Radio Presets
Dimensions: 7in x 2in x 6in

Click HERE to See FULL Size picture

I recently picked up a MINT Alpine 7288 and thought it was important to write an article and create a demo video showing off the unit. Click HERE to see the full specifications.

Although I was able to test the unit for functionality, I did not do a full test. The tape mechanism sounded rather loud to me, it may have always been this way, but I didn't want to stress it out. It most likely needs a new belt for the tape drive, but I don't know for sure. I was extremely impressed all features appeared to work properly and the FM tuner was working even without an antenna plugged in...now that's a sensitive tuner!! Unfortunately, I didn't have a 5952 or 5959 CD Changer to test out the controller functionality, but hopefully I'll come across one soon.

See more up close and personal pictures below:

Alpine 7288 Left Front Side

Alpine 7288 Front Right Side - Classic "chicklets"

As you can see in the pictures, the display is bright and clear. The buttons show very little wear, even less than my near mint Alpine 7903 CD Tuner. I used a soft brush to remove the dust, you may be able to see I missed some....dang those DSLR's!

One last picture I'll show before the video is the DIN plug and RCA Pre-Amp outputs. See below:

Alpine 7288's DIN Plug for CD Changer and RCA Output Jacks

Alright, so we all know a picture is worth 1000 words, so how much is a video worth? Well, for me, it all depends on the quality. The video below was captured in 1080/24P using my Canon 7D. I was planning on recording audio using an external device, but decided the internal mic would suffice for the tape sounds and output sounds. As I note in the video, I was using a small 4" dual-cone speaker, so don't expect any impressive sounds from the Tuner and Tape playback tests. Enjoy the video!

Make sure to Subscribe to my YouTube Channel to stay updated of my latest videos. You can also follow me on Twitter @oldschoolstereo.

See the video on YouTube in 720p HD or embedded below:

Tuesday, December 13, 2011

Rockford Fosgate Power 650 Mosfet - True Old School Powerhouse

Late 80's Rockford Fosgate Power 650 Mosfet

Think old school power....think names like Orion, Precision Power and Rockford Fosgate. Up for review today is a late 80's Rockford Fosgate Power 650 Mosfet. This amp is an icon of the infamous Mosfet Power series by Rockford. People know the Power 300 as the "entry level" power series amp (MSRP $999*) and the "ultimate" power series as the Power 1000 Mosfet (MSRP $2650*). But why no respect for the big brother, Power 650? It's always tough to be the middle child! The Power 650 retailed for $1575* in 1990 and was available from approximately 1985-1993.

(*Pricing above was verified in an April 1990 Car Audio & Electronics Car Stereo Directory)

Here are the specs of the Power 650 Mosfet:

Power Ratings: 4 Channel

4 Ohms: 125 watts per channel continuous power into 4 Ohms, 4 channels driven, from 20 to 20,000Hz, with less than 0.05% THD + N (Total Harmonic Distortion & Noise).
2 Ohms: 162.5 watts per channel continuous power into 2 Ohms, 4 channels driven, from 20 to 20,000Hz, with less than 0.1% THD + N.

Power Ratings: 2 Channel (bridged) 4 Ohms: 325 watts per channel continuous power into 4 Ohms, 2 channels driven, from 20 to 20,000Hz, with less than 0.05% THD + N.
Frequency Response: 20 to 20,000Hz, ± .5dB
Bandwidth: 15 to 20,000Hz, ± 3dB.
Damping Factor: greater than 200 at 50Hz.
Slew Factor: greater than 2.5.
Slew Rate: greater than 10 volts per microsecond.
Protection: The Punch also employs thermal switches which protect the amplifier from overheating damage. Fuses are provided for speakers which are directly connected with no crossover components.
Dimensions: 18 3/10” long x 8 1/10” wide x 2” high, exclusive of knobs and wiring. 19 3/10” long x 8 1/10” wide x 2%” high, minimum mounting requirements.

Disassembled Power 650 Mosfet - Fan Shroud, Amp "guts", bottom plate and fuse cover

You young kids out there don't know much about Class A/B subwoofer amps with the $300 1500-watt Class D amps you have today. The Power 650 and Power 1000 were classic subwoofer amps in their day. Instead of using DVC subs with "fat" surrounds, we had 15's, 18's and even 30" subs (See Wayne Harris' 1985 Terminator Hearse)!!! No mention these old school subs in many cases were 8 ohms, used in multiples and had an x-max of 10 or 12mm if you were lucky...We still appreciate the "Made in the USA" quality of these amps and the pride the workers put in each and every amp. Shoot, the Rockford amps were even smacked with a rubber mallet to ensure they could handle the "punch" as part of their QA process!

One feature lacking on the Power 650 you would find on the Power 300 was bass and treble controls. For the most part, if you could afford a Power 650, you could most likely also afford a matching "Z or ZX" preamp. These preamps had EQ adjustments and even fancy LED lights as a VU meter.

Bottom side of the Rockford Fosgate Power 650 Mosfet

In addition to being a powerful four-channel amplifier, the Power 650 is also a very flexible amp. In the mid to late 1980's there were only a handful of amplifiers with built in crossovers...the Power 650 being one. Unlike modern amps, the crossover settings are set at certain frequencies (instead of being fully-variable). Also, note the high crossover's cutoff begins at 140Hz, whereas the low pass could be set as low as 70Hz. It could be used in four, three or two channel operation. My initial RMS wattage tests have shown the Power 650 ratings to be conservative, more on this in an upcoming video and article.

Early Rockford Fosgate Power 650 Mosfet with DIN and RCA Inputs

Those familiar with the Power 650's know in addition to there being DIN/RCA and RCA only models, there was also a short run of the last Power 650's with a 4-inch fan as opposed to the 2-inch model available since the mid-1980's. From my research, the 4-inch models were the last production Power 650 mosfets and were produced in low numbers. See pictures and some more detail here: http://www.gamblin.net/power650.html

Stay tuned for the RMS wattage output demo of the Rockford Fosgate Power 650 Mosfet. Make sure to Subscribe to my YouTube Channel to stay updated of my latest videos. You can also follow me on Twitter @oldschoolstereo.

See the video on YouTube in 720p HD or embedded below:

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See the Old School Rockford Fosgate Power 650's in ACTION! Wayne Harris' "Terminator" Hearse Vintage 1985

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Friday, November 18, 2011

SMD's DD-1 - New School Tool for Old School Amp Testing

SMD's DD-1 "Distortion Detector" vs. Velleman HPS50 Oscilloscope

Many of you who follow my blog and videos, know I've had a Velleman HPS50 oscilloscope for a while now and keep adding components to enhance the capabilities of my test bench. My primary focus now is testing amplifiers for maximum continuous RMS wattage output. We all know most of the ratings we see on amps today are not RMS, but MAX output. This is a marketing ploy, not useful at all in determining the actual output of an amplifier. I'll soon get one of these amps on the bench and show you actual RMS wattage output vs. the value claimed on the amp. You may be amazed and not laugh so much at the old school amps and their low wattage ratings...

I recently decided to pick up a SMD DD-1 "Distortion Detector". This device was developed by the brains at D'Amore Engineering in conjunction with the KING of car audio on the Internet, Steve Meade (www.stevemeadedesigns.com). Steve Meade (meade916 on YouTube) is famous for his 30,000 watt custom Chevy Tahoe and has several hundred videos. Steve is also the largest car audio channel on Youtube with over 100,000 subscribers and over 100 MILLION video views. Impressive to say the least, but this DD-1 is not hype, it is a truly powerful and affordable tool for everyone from electronics enthusiasts to car audio shop installers and many in between.

So, what's the deal with this DD-1 and why might you want one? The SMD DD-1 is marketed as an amplifier gain matching tool. Matching your car audio head unit and amplifier has been a black art for many years. Without an oscilloscope and test tone, setting gains was really just a guess for most folks. The DD-1 costs only a fraction of most oscilloscopes and offers simplicity in setting/matching gains for your car audio equipment.

Here's what's included in the package:

The Distortion Detector (DD-1)
Protective silicon rubber boot
Calibrated Test Tone CD
Harness
Printed owner's manual

According to the manual, the DD-1 has the following specs:

The DD-1's circuitry is 100% analog
Distortion Detection trigger level > 1.0% Harmonic Distortion
Guaranteed operating range of input signal is 1.2Vrms - 125Vrms (15,000 Watts at 1 ohm) Autoranging
Signal Present LED trigger voltage 750mVrms
Low Battery LED trigger battery voltage < 5.6Vdc
Auto shut-off timer 8-10 minutes after on button is pressed

Now, I must be honest. The unit's ability to match gains is a great feature, but I've had this ability with my Velleman HPS50 portable o'scope for a while. A recent video on Steve's channel about the upcoming AD-1 "amp dyno" got the wheels spinning in my old school head. This DD-1 can be used for more than just matching gains...it can be used to assist in amplifier output testing! This feature in a sub $200 device is unheard of. A bench version of a THD analyzer can cost MANY thousands of dollars. I've been watching eBay for a year or more hoping to find a deal on one of these THD analyzers so I could verify distortion during my amplifier tests. After seeing the AD-1 demo, I was convinced to buy the DD-1 to use as a tool in my RMS output tests.

The DD-1 has proved to be an invaluable tool and will ensure accuracy in my amplifier tests. I have MANY old school amps I plan on testing in the upcoming months. The DD-1 will ensure < 1% distortion in my results which is great. As I mentioned above, not only do many manufacturers rate amps by "Max" output, they also sometimes use distortion numbers up to 10% for their ratings. I think it's important to keep the distortion less than 1%, which should be inaudible for most people.

I have done some initial tests with the DD-1 and have been impressed with it's ease of use and ability to detect low levels of distortion. See some videos below and be sure to subscribe to my YouTube channel to stay updated with the latest amplifier and car audio tests and demos.

Buy the DD-1 Direct at wccaraudio.com

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Sunday, November 6, 2011

Rockford Fosgate PBR300x1 "Boosted Rail" Amp

Old School Orion 222 SX vs. Rockford Fosgate PBR300x1

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As we all know, technology has a way of "shrinking" electronics over time. Have you ever seen an early laptop computer? Or how about a 1st generation iPod? Compared to the latest laptops and iPods, the first generation models are large and clunky.

Transition over to car audio amplifiers. Although this is OldSchoolStereo.com, I still appreciate technology and have been eager to try out one of the new "mini" amps currently on the market. One which grew particular interest is the Rockford Fosgate PBR300x1. This amp measures a tiny 6-3/4"L x 4-1/4"W x 1-1/2"H, small enough to fit in the tightest automotive locations. Here are the full product specifications:

mono subwoofer amplifier

75 watts RMS x 1 at 4 ohms (150 watts RMS x 1 at 2 ohms)

300 watts RMS x 1 at 1 ohm

CEA-2006 compliant

Boosted Rail amp technology

Dynamic Thermal Management cooling system

variable low-pass filter (35-250 Hz, 12 dB/octave)

differential-balanced inputs eliminate noise from your vehicle's electrical system

preamp and speaker-level inputs

optional wired remote bass boost (0-18 dB at 45 Hz)

10-gauge power and ground leads and a 30-amp fuse recommended — wiring and hardware not included with amplifier

no onboard fuses — when installing multiple amps in a system, an additional 30-amp in-line fuse between the distribution block and the amplifier is recommended

6-15/16"W x 1-9/16"H x 4-5/16"D

Something I noticed immediately after opening the box was the inclusion of molex-style connectors for the amp. Am I missing something here or are we going back to the early 1990's? I couldn't help to think of the 1991 Punch 30HD which uses similar connectors. See pictures below for all of the connections, plus a size comparison to the 30 watt Punch 30HD.

PBR300x1 connections including crossover, gain, hi/low input and Remote Punch EQ

PBR300x1 Speaker output and Power connections

2011 PBR300x1 vs 1991 Punch 30HD - 300 watts vs. 30 watts!

Ok, so an amp almost small enough to fit in your pocket can deliver 300 watts? Well, according to the birthsheet included with my PBR300x1, it will actually do 315 watts RMS at 1 ohm (14.4v)! Impressive numbers from such a small amp, but how does it sound powering subwoofers?

Well, you can see (and hear) first hand by watching my video below. I auditioned the PBR300x1 on my test bench with subwoofers including; 8" JL Audio 8W1, 10" Kicker Solobaric S10c and 12" JL Audio 12W6v2 D4. The results were impressive, to say the least. I'm really looking forward to getting the amp in my daily driver for a true test of this little beast and how it performs in the harsh automotive environment.

Stay tuned for an upcoming power output test of this amp. Make sure to SUBSCRIBE to my YouTube Channel to stay notified of my latest video uploads.

See the mystery "unboxing" of these Old School Gems below:

Video in 720p HD

or embedded below:

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Sunday, October 2, 2011

Soundstream Reference 300 Power Output Test

Soundstream Reference 300 on the OldSchoolStereo.com Test Bench

I recall back in the early 90's patiently awaiting my monthly Car Audio magazines so I could see amp tests. It was very rare to come across a test I actually cared about, but maybe once a year or so. I drooled over the Phoenix Gold MS series, Rockford Fosgate HD series, Soundstream Reference series, just to mention a few. Well, these days, I spend some of my free time bench testing some of these amps I always wanted back in the day.

I recently picked up a Soundstream Reference 300 and couldn't wait to add it to my old school 150 watt (75x2 RMS) amp tests. If you've missed it, I've already done an overview and RMS watt output test of the Phoenix Gold MS-275 and Rockford Fosgate Punch 150HD.

The Reference 300 is a no-frills old school amp. It has no internal crossover and as with earlier Soundstream amps, all connections are made on one side. There are also two openings on the bottom of the amp with switches. One switch controls high power or high current mode, while the other allows switching between mono / coherent stereo / mixed-mono modes. The Reference 300 is rated to handle 1/2 ohm loads in stereo or 1ohm modes in mono, while in the high-current mode. High power modes are designed for loads down to 1 ohm stereo or 2 ohms mono.

See power output specs from the manual below:

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Soundstream Reference 200/300/500 Power Ratings at 12v

Also, here are some of the design specs of the Soundstream Reference Series amplifiers:

Soundstream Reference Series Design Features

The ability to drive 1/2 ohm loads was a rarity back in the early 90's. Only a handful of amps were rated to handle these loads. Orion HCCA models come to mind, but there were others from US Amps and Phoenix Gold, to mention a few.

As for the power output test, I was anticipating Soundstream to rate the Reference 300 conservatively. As you may have seen already, the Rockford Fosgate Punch 150HD was rated at the same 75x2 at 4 ohms and delivered nearly 120x2 at 4 ohms on the OldSchoolStereo.com test bench. Many manufacturers during this time rated their amps based on 12v, not the 14.4v you see today.

150 Watt Old School Amps from Phoenix Gold, Rockford Fosgate, Orion & Soundstream

So, enough talk already, how did the Soundstream Reference 300 perform on the bench? Well, now that you asked, here are the measurements (All taken based on 100Hz test tone and 13.8v input).

Continuous RMS Wattage Output:

4 ohms Stereo - 105.6 watts/ch (both channels driven)
2 ohms Stereo - 134.1 watts/ch (both channels driven)
4 ohms Mono - 267.3* watts (in high-power mode)
2 ohms Mono - 224.7 watts (in high-current mode**)

*See the update video below for the updated 4 ohm mono test
**The Reference 300 popped it's 30A fuse when I attempted 2 ohm mono testing in the high-power mode.

See the power output test in in 720p HD or embedded below:

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UPDATE: One more demo to see if the 4 ohm bridged mono mode would yield the rated 300 watts:

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Keep watching and subscribe to my YouTube channel to stay updated with my latest Old School Car Audio tests and demos.

-BigD

Thursday, September 22, 2011

Unboxing Old School Car Audio Gear

I will be the first to admit, unboxing videos do not appeal to me. Why? Mainly because people do unboxings for things like cameras, camcorders, computers, etc. and there is no excitement factor there. Now, take a plain brown box (with unknown goodies inside), open this up on camera and share your excitement with the world! This is how BigDWiz does unboxings at the OldSchoolStereo labs!

First off, I must say not all of the unboxings I do on my YouTube channel are from purchases. Many are from trades and barters for other gear. This is a part-time gig for me and I don't have unlimited funds to buy all of this cool, old school equipment. Well, since I know opening these packages is exciting for me, I thought you guys might enjoy the experience?

OldSchoolStereo.com Mystery Box!

Finding nice, old school car stereo gear is exciting in itself, but opening a package with unknown contents (well, unknown to you) is fun for all. Those of us who enjoy the old school gear also love to see "timeless classics"...the amps, speakers, head units, etc. that have either been babied or unused all of these years. I still find it amazing to see the condition of some of my 25+ year old equipment.

Most of these videos will just show the unboxing process, but in some cases, I may hook up and test the contents. Honestly, it just depends on how I'm feeling at the current time (and how much space is remaining on my iPhone's internal storage!). This brings up another interesting point....some of you may wonder what equipment I use to record and produce these short videos. Well, I have two words for you; iPhone and iMovie (we won't count "and" as a word!).

Recently, I've discovered making videos with the iPhone 4, is not only a simple process, but also gives a pretty good output video for viewing online. I also ensure use of the included ear buds / mic combination to get better audio, while still leaving both hands free to tear open the boxes. Once I capture the segments on my iPhone 4, basic editing is handled by the iMovie app for the iPhone. This $5 app turns your iPhone into a VERY powerful hand-held editing machine. If there is any interest, I may show the process I use to capture, edit and upload my videos to YouTube. You guys just let me know by making comments here or on my YouTube Channel.

While you are visiting, please Subscribe to my channel so you can get notification when I upload a new video. My intentions are to upload a new video every few days. As I've mentioned before, the more subscribers, comments, likes, etc. I have, the more videos I'll put up. I appreciate your enthusiasm as being an "old school nut" is addictive!

Unboxing Old School Car Stereo Gear
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Unboxing Old School Car Stereo Gear #2
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Unboxing Old School Car Stereo Gear #3
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Unboxing Old School Car Stereo Gear #4

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Thursday, September 15, 2011

Old School PPI Pro Mos Amps - Precision Power!

Most of you old school car audio fans know the early 1990's was a time when aftermarket car audio was getting extremely popular. At this time, it was rare to find a factory CD player and the factory speakers were weak at best in most cases. Manufacturers such as Rockford Fosgate, Linear Power, Precision Power (PPI), Autotek, Orion and Soundstream (to name a few) were some of the very popular aftermarket car audio brands at the time.

The competition between the manufacturers was intense and each one was trying to best the other. Orion's HCCA series amps, released in the late 1980's were extremely popular and had an edge power wise on most other amps with their rating and ability to handle extremely low ohm loads. These low-wattage rated / low ohm handling amps came to be known as "cheater amps". The cheater amps could put out as much as 8x their rated 4 ohm power rating at lower loads. PPI hit the "cheater" market in 1990 with the Pro Mos 2050. Pro Mos was short for Professional Mosfet. This first gen Pro Mos amp was rated to handle loads down to 1ohm and would provide 4x it's rated 4ohm power at 1ohm. Cough up around $800 for a 50x2 amp, and get a 400x1 monster when loaded down. Interestingly enough, Orion's 25x2 "cheater", the 225 HCCA was stable down to 1/2 (some even say 1/4) ohm loads and would put out in excess of 400 watts and cost less than $600.

I've shown a comparison of the Orion 225 HCCA and the PPI Pro Mos 25 in a previous posting and video. You can see my preliminary power output results HERE.

PPI Pro Mos 2050 (top), Pro Mos 12 & Pro Mos 25 - Image (C) OldSchoolStereo.com

These Pro Mos amps were available up until around 1995, adding additional models including the Pro Mos 12, 24 and 50 (replacing the 2050) beginning in 1991. They also released 4 channel models; the Pro Mos 425 and 450. These Pro Mos amps were no frills, offering no internal crossovers or bass/treble controls. They offered a DIN connection for powering a PPI pre-amp or crossover in addition to the standard RCA input jacks. The Power and Ground connections were made via 8 or 10 awg leads and the speaker/remote connection was made by an infamous molex connector. I say infamous because this connector has been a huge failure throughout the years. The wires don't stay inside the connector and the molex connector itself breaks very easily. Many people created terminal strips or soldered the leads to the circuit board.

The Pro Mos amps you see in the photo above are the "art series", finished in white including a unique design by an artist. These amps were also available in black with red lettering.

See the video demo below:

Also, visit YouTube and subscribe to my channel for more exciting OLD SCHOOL car audio gear!

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Saturday, September 10, 2011

Vintage Fosgate Car Amps - PR 220 & PR-250 Pre-Rockford

Fosgate PR-250II and PR 220 Vintage Car Audio Amplifiers

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I decided to dig out some real dinosaurs in the car audio world....the Fosgate "The Punch" PR 220 and PR-250 Type II amplifiers. These amps were produced by Fosgate Electronics, Inc. in the late 1970's before Rockford joined Fosgate. I believe the PR-250 was 1978 or 1979 and this model was also produced in 1980 as a Rockford Fosgate PR-250II (logo was different than the one pictured above). The PR 220 was also late 1970's, found in the 1978 and 1979 Car Stereo Directory issues of Audio magazine, but not in the 1976 issue. I don't have the 1977 issue to see if they are listed there...

These amplifiers were state of the art at the time they were produced. Just think, in the late 1970's, many people were still rocking 8 tracks and a cassette player was "high-end". I don't believe there were many (if any) head units with pre-outs at the time. You definitely were lucky to have one of these back then. Don't forget, 3-way 6x9's were considered high-end at this time! Take your PR-250, power up the Sony tape deck and Jensen or Sparkomatic 6x9's and you were rockin'!!

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Another view of the Fosgate "The Punch" PR-250 Type II / PreAmp & PR 220 Amplifiers

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The Fosgate PR-250 Type II had a matching Pre-Amp, which controlled the unit's volume, bass and treble controls. The volume knob was a smooth rotating potentiometer, while the bass and treble controls had a "clicking" type potentiometer (meaning you had only a certain number of positions, by turning these knobs, it would click into position). The PR-250's pre-amp had only two connections, both DIN style plugs. One DIN cable would be integrated in with your head unit and the other would carry the signal from the pre-amp to the PR-250 amp. Then, you would need some speakers capable of handling 50 watts RMS per channel, not the easiest task in the late 70's...The PR-250 was also bridgeable or capable of handling loads more demanding than 4 ohms.

The Fosgate PR 220 was much simpler and less powerful than the 250. It was rated at 20 watts x 2 channels into 4 ohms, no options for bridging or lower ohm loads. It also came without a pre-amp, all controls (bass and treble) were on the amp itself by 3-way sliders. Your options were low/mid/high for bass and treble adjustments. Again, speaker level inputs were the only signal source allowed into the amp and since most head units were only good for a couple of watts, the 20 watt PR 220 was a decent upgrade and would drive efficient speakers to loud (at the time) levels, around 110dB. Fosgate had a warning in the manual, "Sound levels of 110 dB have been recorded inside a car using the PR-220 and High Efficiency speakers. This is loud enough to lead to permanent loss of hearing after long periods of exposure. So use common sense.."

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So, you know me, I'm good for putting up video demo's right? Well yes, I have posted an overview of the amps below. That said, don't get too excited about seeing these amps in action as I'm a little hesitant to power them up. The PR 220 at least needed to pull power from the head unit for the remote turn on.

Quote by tomtomjr, one of if not the US's largest Fosgate/Rockford Fosgate collector and radio/amp technician:

" ...ALSO, on the turn on remote wire (red) , you will need to draw power from it to turn on the amp. We used to use a 12V light bulb and a switch. Put the remote wire (red) to the positive of the bulb, then the switch between the 12V ground and the 12V ground of the bulb. Flip the switch, and it will come on. These have the power-draw on the remote wire rather than the power input like modern amps... Hope this info helps........Tom"

See the video demo in 720p HD or embedded below:

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Thursday, September 8, 2011

Video Overview of the Rockford Fosgate Punch Power 360

I recently created a video overview of the Rockford Fosgate Punch Power 360 I wrote about before. Enjoy the video demo below:

View in 720p HD or watch embedded below:

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