• Daily Deals
  • Gift Cards
  • Sell
  • Help & Contact
  • Shop Deals

Bidding has ended on this item.

Ships to:
United States
Ships to:
United States


See original listing
Item Sold
Item condition:
For parts or not working
Mar 04, 2012
Winning bid:
US $155.89
12 bids ]
$41.15 Economy Shipping | See details
Item location:
SE Michigan, United States


eBay item number:
Seller assumes all responsibility for this listing.
Last updated on  Feb 27, 2012 05:50:24 PST  View all revisions

Item specifics

Condition: For parts or not working Channels: 2 Channel

For Parts or Repair

CEC AMP 3300

  Pure Class A Single-Ended Amp

The AMP3300 is a Class A amp that features an extremely pure single-ended circuit

with each one single transistor for the non-inverting and inverting lines,

that handles all music signal processing.

Earlier Class A amps were inefficient, had extremely low output and generate considerable heat when operating,

but the AMP3300 uses a load effect free (LEF) circuit to successfully combine high-efficiency power with high-quality pure Class A amplification.

The primary technology of the LEF is to avoid various sources of nonlinearities.

CEC's Original LEF Circuit

The AMP3300 features CEC's unique load effect free (LEF) circuit to avoid completely all factors that result in deterioration of sound quality.

The LEF circuit makes possible pleasing and detailed playback as well as a high efficiency.

Every amplifier should be a perfect voltage source in theory, while the current into the speaker is likely out of phase in relation to the voltage.

The phase relation varies with the frequency and is even dynamically moving. NFB amplifiers are sensitive to this matter, specifically to the dynamic changes.

The LEF's current control stage is not linked to the signal voltage,

and just checks the current requirement that depends on the speaker load without "knowing" about the phase relation to the voltage.

This "phase independent operation" is an important reason for the obvious drive ability as well as sound quality.

The AMP3300 also has an automatic bias adjust function for stable signal processing.

Fully Balanced Signal Processing Circuit

The AMP3300 adopts a full-balanced circuit design to achieve extremely high-speed and low-distortion signal transmission.

Unbalanced inputs are converted to balanced in the very first stage of the amplifier with no deterioration of sound quality,

resulting in a fully balanced output signal that drives the speakers.

In addition, the left and right signals are processed in circuits divided into two layers to ensure channel separation and a high-level stereo image.

IGM Volume Control

The newly developed Intelligent Gain Management (IGM) system is used to minimize signal loss during volume adjustment.

Sound volume is adjusted by controlling the gain itself with a knob on the front panel.

The input signal is not degraded by any mechanical volume resistor or CMOS device.

As a result of this, lowest noise, low distortion and highest dynamic performance has been achieved.

No-Feedback Structure

The AMP3300 has an LEF circuit that makes possible extremely stable and realistic amplification, and since a NFB loop is fundamentally unnecessary in the signal path,

the shortest-possible, truly straight signal route is achieved.

The AMP3300 is a completely feedback-free power amp in the signal path that can express

all data perfectly with a single voltage amplification and a single current amplification.

Numerous Input and Output terminals

The AMP3300 has four conventional RCA input terminals (unbalanced) and one XLR input terminal (balanced),

enabling it to connect to high-quality products with balanced outputs such as CEC's CD5300. In addition,

the AMP3300 can be connected to a recording device,

such as tape recorder as well as active sub-woofer.

The speaker outputs are spring-loaded terminals that are simple to connect the cables,

but not come loose easily.

Technical Data

 Rated output: 2x 60 on 8Ω, 2x 100 W on 4Ω

  Frequency response 0.2 Hz to 80 kHz - 3 dB

  Gain: 22 dB / XLR, 28 dB / RCA (max. volume)

  Total harmonic distortion: 0.025% / 50 mW

  Signal to Noise ratio: 102 dB (1W/8 Ω)

  Channel separation: > 100 dB at XLR output, > 90 dB at RCA output

   Input terminals: 1x balanced XLR, 4x unbalanced RCA

  Output terminals: Tape rec. (RCA), speaker

  AC power voltage: 120 / 230 V / 50 / 60 Hz

  Power consumption: min. 32 W, max. 300 W

  Dimensions: approx. 435x100x360 mm (WxHxD)

  Weight: 9,2 kg

  Color: Black.

Originally sold for $975





LEF technology: The future just begins!

Avoiding a mistake instead of correcting a mistake

Distortions and other sound degradations of amplifiers are due to one main reason: The signal is

running through the non-linear characteristic of transistors or tubes. (Other distortion sources,

like poor power supply and component parts, are avoidable by proper engineering.) Triode tubes,

pentode tubes, FETs and transistors have different characteristics, but one common fact: They

are all non-linear! If their characteristic would be linear, it would be easy to build good sounding


The common way to reduce measurable distortions is negative feedback (NFB). At the first look

this method seems to solve the problem, but only for static test signals, not “random” music signal

– looking good on measurement equipment and paper, but with the usual limitations in sound we

all got used to.

As there are no common ways to test short time (transient) distortions, which happen during fast

signal changes, most engineers assume they don’t exist. Prof. Mati Otala developed a way to

measure TIM – Transient Intermodulation, which this is only a small part of the whole story.

Carlos Candeias succeeded in proofing these short time distortions, which origins from NFB

limitations. As a consequence the development of amplifiers without negative feedback, as well

as very low dynamic and static distortions was initiated. (There are already amplifiers without

NFB on the market, but with sound influencing distortions.)

LEF avoids degradations of sound instead of “correcting” it afterwards.

The breakthrough of LEF circuit is: The signal transistor does not pass through its voltage

characteristic Vce nor the current characteristic Ic.

Passing the voltage characteristic is avoidable by using floating cascode circuit. This is known,

but causes s loss in efficiency and power when using traditional circuitry.

As the signal transistor in LEF circuit does not handle the current requested by the speaker, loss

in efficiency is negligible.

LEF’s most important progress is splitting the handling of the loudspeaker’s current request from

the music signal voltage output stage!


LEF means load effect free. This means: The signal transistor is not loaded by the speaker’s

current request, because he has strong current handling “assistants” – thus no sound

degradation effects due to the load happens.

With today’s common amplifiers it is easy to hear whether it sounds like an airy ballet dancer or a

heavyweight bodybuilder, because the music signal has to pass the more or less “heavyweight”

output transistors.

In LEF technology the fast, airy and delicate signal transistor and the heavyweight current

assistants work, supporting each other. However, the current assistants are not “allowed” to take

part of the signal voltage. This means: The signal transistor does not pass through his current

characteristic Ic. The load, usually the speaker, “sees” only the signal transistor, but no “current

assistants”. This is due to the signal transistors very low output impedance, combined with the

very high output impedance of the “current assistance”. In case of some small current

imprecision that may occur, the “current assistants” are safely “overruled” by the signal transistor.

Unlike usual amplifiers the LEF amp sounds like unlimited power, as long as it works within the

designated power range; combined with speed and colourful elegance.




Volume control -- ( IGM - Intelligent Gain Management )

The non-feedback LEF circuitry allows a new way of volume control. Instead of losing more of less

signal quality IGM increases the sound quality.

An IGM amplifier varies the gain through the whole range of required music volume, without

wasting any music signal. As a result IGM achieves higher a signal-to-noise ratio, higher voltage

amplifier stability and therefore better dynamic performance, stable stereo image and more power


One channel does not play,   the other produces the most incredible sound!

For Parts or Repair

Payment in three days or less.


Questions and answers about this item

No questions or answers have been posted about this item.

Place bid

Time left:
Current bid:
(Approximately ##1##)
Import charges:
Your max bid:
Your max bid:
By clicking Confirm bid, you commit to buy this item from the seller if you are the winning bidder.
By clicking Confirm bid, you are committing to buy this item from the seller if you are the winning bidder and have read and agree to the Global Shipping Program terms and conditions - opens in a new window or tab. Import charges previously quoted are subject to change if you increase you maximum bid amount.
Resume bidding, if the page does not update immediately.
Place bid
Review and confirm your bid
Bid confirmation
FREE shipping
See item description
(Approximately ##1##)
(Enter ##1## or more)
(Enter more than ##1##)
Your max bid:
Increase max bid
Place bid
Confirm bid
Increase max bid
Change bid
, you've been outbid. Don't let it get away - bid again!
, you're the highest bidder on this item. Hope you win it!
, you're the first bidder. Hope you win!
, you're currently the high bidder, but you're close to getting outbid.
, this auction is almost over and you're currently the high bidder.
, you're the high bidder, but the reserve price hasn't been met.
Please enter your bid again.
Please enter a valid number as the bid price.
Enter an amount that is equal or greater than the minimum bid required. This can be found under the bid entry box.
Maximum bids can't be lowered once they're submitted.
This seller requires the buyer to have a PayPal account to purchase this item. Get a PayPal account here .
Your bid is greater than or equal to the Buy It Now price. We recommend you purchase this item via Buy It Now. If you still wish to bid, you may do so below.
Time left:
Current bid:
(approximately ##1##)
Your maximum bid:
(approximately ##1##)
Increase your maximum bid:
By clicking 1 Click Bid, you commit to buy this item from the seller if you're the winning bidder. Learn moreabout 1-click bid - opens in a new window or tab
(approximately ##1##)
Winning bid:
Starting bid:
Congrats! The auction has ended and you're the winner.
The auction has ended, but the reserve price was not met.
Sorry, the auction has ended and you were outbid.
Good news, you're the high bidder.
Sorry, you've been outbid.
You're the high bidder, but the reserve price is not met.
Please enter a higher amount than the current bid.
Maximum bids cannot be lowered once submitted.
Please enter a valid number.