Friday, December 30, 2011

Santa Visited OldSchoolStereo - More Old School Goodies!

Yes, it's true...Santa dropped off some Old School Car Audio for everyone to enjoy!

First up is the Rockford Fosgate PBR300x4 "boosted rail" amp to match the PBR300x1 I already have and have tested in a previous video. The 300x4 is a 4 channel amp rated at 75 watts for each of the 4 channels and is not bridgeable. It is the same TINY size as the 300x1 and will work great for a stealth install. More details coming soon on this...

Next up is a rare Infinity Nucleus KPX-2 tri-mode crossover system. This item also came with the optional FC-1 fader control for Front/Rear control. Take an old school 2 channel amp and power an entire system with mids/highs up front, mids/highs in the rear and a subwoofer. The Nucleus KPX-2 offers a 12dB low pass crossover slope at 75hz and a 6dB high pass filter at 150hz.

Last, but not least is a Soundstream Dealer's manual from the mid 90's called the "Heavyweight Boxing" Subwoofer Enclosure design installation manual. It is an extremely detailed with specs of the Soundstream subs of the time (SSR, Granite and SPL models). This extra large manual was for Soundstream dealers and had an original MSRP of $249 and even has a serial number!

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

See 3 of the latest items arriving at the Labs. I show off two subwoofers and an ultra-rare NIB set of Boston Acoustics 767 coaxials.

First, you'll see an early 90's Rockford Fosgate PCH-812 "The Punch" Classic 12" 8 ohm subwoofer in MINT condition. Next up is an ultra-beefy 10" sub from Eclipse, the 8810.6. This is a single 6 ohm subwoofer made by TC Sounds. 600 watts RMS, 3" peak to peak excursion and an original retail price of $370 make this a desirable sub, especially in it's very good condition!

Last up is the unbelievable...a BNIB set of Boston Acoustics 767 6.5" coaxials. Per Boston's website, these were made between 1987 and 1993. So, these speakers have been sitting in the box, untouched for possibly over 20 years? Simply amazing!

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

See my latest amp arriving at the labs....a MINT Rockford Fosgate Power 500m amplifier, in the box complete with birthsheet! According to an April 1995 Car Audio & Electronics Directory, the 500m retailed for $929 back in 1995. This amp and the 250m2 were Rockford's most expensive amps as the infamous 4 channel Power 300, 650 and 1000 had been retired from Rockford's lineup around 1993 or 1994.

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:

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:


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


Sunday, December 4, 2011

700 Watt Mini Amp? Lepai LP-V3 Tested and Reviewed

Lepai LP-V3 Mini Amp

The Chinese Mini Amp Invasion continues!! Next up is the Lepai LP-V3. This mini amp touts use of a BOSE power IC. In fact, the non-grammar corrected text "This Amplifier is use BOSE Power IC" is silk-screened on the amp. You'll also see "700 W Max Music Power" labeled on the amp. The LP-V3 uses the exact same enclosure as the LP-2020A+, I reviewed earlier.

See a size comparison w/ the LP-2020A+ below:

Lepai LP-2020A+ and LP-V3 Mini Amplifiers

In addition to touting a BOSE IC, the LP-V3 promises an RMS Power Output of 25 Watts. No clarification if this 25 Watts is per channel or total watts...

The next two pictures below show both ends of the for the controls, the other for the connections. Here again, the LP-V3 is a clone to the LP-2020A+:

Lepai LP-V3 Controls; Power, Tone/Direct, Bass, Treble & Volume

Lepai LP-V3 Connections; RCA, 1/8" inputs, Spring-Loaded Speaker Terminals and 12v5A DC  Power Input

Well, enough about the connections and controls, how does the LP-V3 sound? Well, in a nutshell, weak. I was expecting much more dynamic and punchy sound as delivered by the LP-2020A+. The LP-V3 appeared to run out of steam quickly and obviously didn't put out anywhere near the power of the 2020A+. In fact, the LP-V3, reminded me greatly of the tiny and unimpressive Kinter MA-150 I tested earlier. Very disappointing, especially considering the supposed "Real" RMS output of 25 watts. I was beginning to seriously doubt the validity of this claim. Fortunately, I have an easy way to determine the actual RMS output of this amp...

Results? Not impressive and not even close to the 700 Watt, or the 25 Watt RMS ratings. Using a 12V 35Ah Sealed Lead-Acid battery showing 13.0V of charge, I was able to obtain:

Output Test Results:

  • 4.43V RMS of Unloaded Output at the speaker terminals
  • 2.0 Watts RMS / channel at 8 ohms
  • 3.6 Watts RMS / channel at 4 ohms
  • 5.1 Watts RMS / channel at 2 ohms
  • 11.9 Watts MAX / channel at 2 ohms

(tests above were conducted using a 1kHz 0dB Sine Wave Test Tone from the SMD DD-1 test disk and output was verified by the DD-1, which detects distortion at 1%. The resistive loads of 8, 4 and 2 were conducted with BOTH channels loaded)

Stay tuned for more tests of these mini amps and see which one (if any) you should buy. Check out my video review of the Lepai LP-V3 below. 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: