GENERAL

Heritage CABS

CLASSIC CABS

SVT-CL

V-4B

HERITAGE SVT-CL

MICRO SERIES

PF-20T/PF-50T

Portaflex Cabs

PRO Series

BA Series V2

External Power Adapter

General

In dating Ampeg Amplifiers, there are several different schemes to be used. The good thing about Ampeg is that when they changed their models, they all changed at the same time. This means that it is fairly easy to determine the range of year by just looking at the outside of the amp. Like all U.S.A. made amps, the speakers, transformers, and potentiometers have date codes on them. This along with the serial number on the amp can help narrow down the year of manufacture.
There are six distinctive periods in the Ampeg line. Each period has a different way of identifying the year made. Note that each different period is approximately during each different ownership. The chart here should be of some help.

Pre 1953: These amps can only be dated by the EIA (Electronics Industries Association) codes on the speakers and other parts. No serial numbers were used during this time.

1953-Mid 1965: In 1953, the first Serialization system was introduced. This was a six-digit number like this: YMMNNN, which was the last digit of the year, month, and number of production. Since there is a possibility of overlap here, cosmetics are a huge factor in determining the year. The year 1953 could be 1963 since only the last digit was used. Ampeg changed their cosmetics several times in the late '50s and by determining whether the amp is black, blue, grey, or tan will identify the year.

1965-1969: In early 1965 a new serialization system went into effect. The old one lasted on certain models for about six months. This system was also six digits. This system here was strictly numerical and started at 000001. It ran for about five years and ended with 092000. This chart is fairly accurate:

    000001-020000 - 1965
    020000-049000 - 1966
    049000-075000 - 1967
    075000-080000 - 1968
    080000-092000 – 1969

The EIA date codes of original components should be used to confirm an approximate date of manufacture.

1970-1979: The third serial number system was implemented in 1970. Not enough information is available to determine the year of manufacture by serial number. An added variable is that during the Magnavox years, Ampeg may have used separate serial number systems for each model or for models that shared the same chassis, like the VT-22 and V-4. The features of the amps from this period can be used and compared to the following table.

Feature Years Used
Blue control panel graphics 1968-72
Black control panel graphics w/square corners 1972-75
Black control panel graphics, horizontally split w/rounded corners (solid-state amps) 1973-79
Black control panel graphics, horizontally split w/rounded corners (tube amps) 1976-79
Distortion control knob 1976-79
White rocker switches (solid-state amps) 1973-79
White rocker switches (tube amps) 1976-79
Black rocker switches 1968-75
Metal “A” logo 1968-75
Plastic “A” logo 1973-79


1981-1985: The MTI-era amplifiers cannot be dated by serial number. Sorry, buddy!

1985-2005: The St Louis Music era. A new serialization system was developed and it became a code used for many years. This is the best way to identify the date of manufacture during this period. A 10 digit number is used as a serial number, which contains lots of information. The number is set up like this: LLLCYMNNNN. LLL stands for the model, C stands for the country. (U is U.K., Y is Europe, W is Worldwide, and D stands for domestic or U.S.). The Y is a year code that is a letter, starting with A as 1988, (see chart below). What happened before 1987 for the year is unclear as very few amps were made because of bankruptcy for MTI. The M is a number code for January-October. (Jan is 1, Feb is 2, Oct is 10, fill in the blanks.) For November and December the letters A and B were used respectively. The last 4 numbers (N) are the actual serial number for the instrument.

A= 1988 F= 1993 K= 1998 P= 2003
B= 1989 C= 1990 G= 1994 L= 1999
Q= 2004 H= 1995 M= 2000 R= 2005
D= 1991 I= 1996 N= 2001  
E= 1992 J= 1997 O= 2002  


2006-2018/19: In 2006 Ampeg was purchased by Loud Technologies Inc. The serialization scheme continued from the SLM era, with recent crossover and slight variations over the years.

XXXXBBYMNNNN, where XXXX is model, BB is build location, Y is year (see chart below), M is 2-week period (A is first week of January, B is second week of January, C is first week of February, you can figure out the rest), and the last numbers (N) are the actual serial number.

S= 2006 C= 2010 G= 2014 K= 2018
T= 2007 D= 2011 H= 2015 L= 2019
Q= 2004 H= 1995 M= 2000 R= 2005
U/A= 2008 E= 2012 I= 2016  
V/B= 2009 F- 2013 J= 2017  


2018/19 – Present: In 2018 Ampeg was purchased by Yamaha Guitar Group. The serial number follows the established 17-character alphanumeric Line 6/YGG scheme.

(21)PPPPMYYWWXXXXXC
(21)= UCC 128 Tag
P=Product Code
M= Manufacturer Code
Y= Year of Manufacture (see chart below)
W= Week of Manufacture
X= Weekly Serial Number
C= Check Digit

68= 2018 70= 2020 72= 2022
69= 2019 71= 2021 73= 2023


*This document borrows HEAVILY from the website www.bluebookofguitarvalues.com and the book “Ampeg: The Story Behind the Sound by Gregg Hopkins and Bill Moore. Thanks guys!

Amplifier Output Type/Power Suggested Cabinet Explanation
SVT-CL
SVT 2 PRO		 300 watts all tube @ 2 or 4 ohms 1 or 2 - SVT810E
1 or 2 - SVT215E
1 or 2 - SVT610HLF
1 or 2 - SVT410HLF
2 or 4 - SVT410HE
2 or 4 - SVT15E		 The SVT-CL and SVT 2 PRO has two output impedances at 2 and 4 ohms
You can mix and match the SVT810 with the SVT215 or the SVT410HE with the SVT15
SVT 450H
B2RE		 450 watts MOSFET (solid state)
Solid State Preamp 		1 - SVT810E
1 or 2 - SVT410HE
1 or 2 - SVT15E
1 - SVT410HLF		 The SVT450 and the B2RE are the same exact amps just with different cosmetics. They have a nominal impedance of 4 ohms but can be run a 8 ohms too.
450 watts @ 4 ohms for optimal power.
250 watts @ 8 ohms
SVT 4PRO All tube pre-amp.
MOSFET power section

RMS Power Output (8 Ohms):
300x2/900 (mono-bridged @ 8 Ohms)

RMS Power Output (4 Ohms):
490x2/1200 (mono-bridged @ 4 Ohms)

RMS Power Output (2 Ohms):
600x2		 In mono-bridged mode:
1 - SVT810E
1 - SVT610HLF
1 - SVT410HLF
1-PR410HLF
1 or 2 - SVT410HE
1 or 2 - SVT15E		 !!!EXTREMELY IMPORTANT!!!
PLEASE READ AND UNDERSTAND OWNER'S MANUAL
You must use the supplied mono-bridged cable to take advantage of the full 1200 watts. This cable is wired +1/+2 at the Neutrik Speakon connector coming out of the mono-bridged speaker out of the back of the 4 PRO
SVT 6PRO All tube pre-amp.
MOSFET power section
1100 watts @ 4 ohms
750 watts @ 8 ohms		 1 - SVT810E
1 - SVT610HLF
1 - SVT410HLF
1-PR410HLF
1 or 2 - SVT410HE
1 or 2 - SVT15E		 Quasi-parametric, all tube preamp. Tube Voltage control which controls voltage for the driver tubes that feed the MOSFET power section. Choose anywhere from 100 volts for an all tube sound to 300 volts for a faster solid state power section
SVT 3PRO All tube pre-amp.
MOSFET power section
450 watts @ 4 ohms
275 watts @ 8 ohms		 1 - SVT810E
1 - SVT610HLF
1 - SVT410HLF
1 or 2 - SVT410HE
1 or 2 - SVT15E		 All tube preamp. Tube Gain control which controls the voltage for the driver tubes that feed the MOSFET power section. Choose anywhere from 100 volts for an all tube sound to 300 volts for a faster solid state power section
B4R Solid State preamp MOSFET power section

RMS Power Output (2 Ohms):
500x2

RMS Power Output (4 Ohms):
340x2/1000 (mono-bridged @ 4 Ohms)

RMS Power Output (8 Ohms):
205x2/700 (monobridged@8Ohms)		 In mono-bridged mode:
1 - SVT810E
1 - SVT610HLF
1 - SVT410HLF
1-PR410HLF
1 or 2 - SVT410HE
1 or 2 - SVT15E		 !!!EXTREMELY IMPORTANT!!!
PLEASE READ AND UNDERSTAND OWNER'S MANUAL
You must use the supplied mono-bridged cable to take advantage of the full 1000 watts. This cable is wired +1/+2 at the Neutrik Speakon connector coming out of the mono-bridged speaker out of the back of the B4R


CABINETS SERIES POWER RATING/IMPEDANCE
PR410HLF Pro Series 600 Watts 4 ohms
SVT 810E Classic Series 800 Watts 4 ohms
SVT 410HLF Classic Series 500 Watts 4 ohms
SVT 410E Classic Series 500 Watts 8 ohms
SVT 15E Classic Series 200 Watts 8 ohms
SVT 610HLF Classic Series 600 Watts 4 ohms

Heritage Cabs

You will only need one cable between your head and the cabinet. The second jack is for daisy-chaining in parallel to a second cabinet.

Yes, just use the upper input jack (4x10 Dual Mode). The impedance will be 8 ohms.

The HSVT-410HLF and HSVT-810E have a warranty of 5 years for electronics and 2 years for speakers, effective from the date of purchase. The warranty is non-transferrable. The original receipt / proof of purchase qualifies as the official warranty card.

Classic Cabs

You will only need one cable between your head and the cabinet. The second jack is for daisy-chaining in parallel to a second cabinet.

Yes, just use the upper input jack (4x10 Dual Mode). The impedance will be 8 ohms.

The SVT-112AV, SVT-212AV, SVT-15E, SVT-410HE, SVT-410HLF, SVT-610HLF, SVT-810AV and SVT-810E have a warranty of 5 years for electronics and 2 years for speakers, effective from the date of purchase. The warranty is non-transferrable. The original receipt / proof of purchase qualifies as the official warranty card.

SVT-CL

Yes. Just make sure your impedance switch on the back of the amp is in the 2 ohm position.

Running the SVT-CL at 8 ohms is not recommended. The Output transformer is tapped for 2 and 4 ohms; running anything other than 'nominal' impedance can put excessive strain on the OT and the tubes, leading to a premature failure.

You would need to use an external step-up or step- down transformer that converts your country's voltage to 120V AC.

Having the 2 inputs is more a convenience than a necessity. Some amps have two inputs, one for active the other for passive. Others have a single input with a Gain knob, and some have a padded selector switch. Some even have a combination: input jack with active/passive switch and Gain knob.
These are all different ways of accomplishing the same thing: preventing a high-output active bass from pushing the amp into unwanted distortion/clipping. When set to Active, the signal is reduced, aka "attenuated", or "padded". A nice feature is a clip light or VU meter that tells you when the amp is clipping. (Note: for some of us, clipping can be a good thing, especially with tube amps or preamps).

At the end of the day, use your ears and pick the one that sounds the best to you.

Yes, plugging in to the 'power amp in' jack completely bypasses the preamp circuit.

The SVT-CL has a warranty of 5 years for electronics and 90 days for tubes, effective from the date of purchase. The warranty is non-transferrable. The original receipt / proof of purchase qualifies as the official warranty card.

V-4B

Yes, just make sure your cabinets are plugged into the '2 Ohms' output jacks on your amp.

Having the 2 inputs is more a convenience than a necessity. Some amps have two inputs, one for active the other for passive. Others have a single input with a Gain knob, and some have a padded selector switch. Some even have a combination: input jack with active/passive switch and Gain knob.
These are all different ways of accomplishing the same thing: preventing a high-output active bass from pushing the amp into unwanted distortion/clipping. When set to Active, the signal is reduced, aka "attenuated", or "padded". A nice feature is a clip light or VU meter that tells you when the amp is clipping. (Note: for some of us, clipping can be a good thing, especially with tube amps or preamps).

At the end of the day, use your ears and pick the one that sounds the best to you.

Since the V-4B is a tube amp, you want to make sure that your speaker impedances are matched to correct outputs of the amp. SPEAKER CABINET IMPEDANCE divided by NUMBER OF CABINETS = TOTAL LOAD

    8 Ω cabs / 1 cab = 8Ω load. For this application use the 8Ω speaker jack.
    8 Ω cabs / 2 cabs = 4Ω load. For this application use the 4Ω speaker jacks.
    4 Ω cab / 1 cabs = 4Ω load. For this application use the 4Ω speaker jack.
    4 Ω cabs / 2 cabs = 2Ω load. For this application use the 2Ω speaker jacks.
    2 Ω cab / 1 cabs = 2Ω load. For this application use the 2Ω speaker jack.

Yes, plugging in to the 'power amp in' jack completely bypasses the preamp circuit.

The V4-B has a warranty of 5 years for electronics and 90 days for tubes, effective from the date of purchase. The warranty is nontransferrable. The original receipt / proof of purchase qualifies as the official warranty card.

HERITAGE SVT-CL

Yes. Just make sure your impedance switch on the back of the amp is in the 2 ohm position.

Having the 2 inputs is more a convenience than a necessity. Some amps have two inputs, one for active the other for passive. Others have a single input with a Gain knob, and some have a padded selector switch. Some even have a combination: input jack with active/passive switch and Gain knob.
These are all different ways of accomplishing the same thing: preventing a high-output active bass from pushing the amp into unwanted distortion/clipping. When set to Active, the signal is reduced, aka "attenuated", or "padded". A nice feature is a clip light or VU meter that tells you when the amp is clipping. (Note: for some of us, clipping can be a good thing, especially with tube amps or preamps).

At the end of the day, use your ears and pick the one that sounds the best to you.

The HSVT-CL has a warranty of 5 years for electronics and 180 days for tubes, effective from the date of purchase. The warranty is non-transferrable. The original receipt / proof of purchase qualifies as the official warranty card.

You would need to use an external step-up or step- down transformer that converts your country's voltage to 120V AC..

PF-20T, PF-50T

1. Push the line cord securely into the amplifier's IEC connector and plug the other end into a grounded AC outlet.
2. Make sure both switches are in the down (OFF and WARM UP) position.
3. Turn the amplifier on by pressing the power switch to the ON position.
The light on the front of the amp will illuminate RED.
4. Wait 30 seconds.
5. Press the Standby switch to the up (PLAY) position.
The light on the front of the amp will illuminate RED.
6. While playing the instrument, adjust the gain and volume knobs to the preferred level.
7. Adjust EQ to taste.

Power Off is the reverse of Power On

Portaflex Cabs

You will only need one cable between your head and the cabinet. The second jack is for daisy-chaining in parallel to a second cabinet.

The PF-115HE, PF-115LF, PF-210HE, and PF-410HLF has a warranty of 2 years for electronics and 2 years for speakers, effective from the date of purchase. The warranty is non-transferrable. The original receipt / proof of purchase qualifies as the official warranty card.

MICRO VR & MIRCRO CL

The audio going into the Audio In jack is routed directly to the Headphones jack, meaning it can ONLY be heard through the headphones and NOT your speaker.

Having the 2 inputs is more a convenience than a necessity. Some amps have two inputs, one for active the other for passive. Others have a single input with a Gain knob, and some have a padded selector switch. Some even have a combination: input jack with active/passive switch and Gain knob.
These are all different ways of accomplishing the same thing: preventing a high-output active bass from pushing the amp into unwanted distortion/clipping. When set to Active, the signal is reduced, aka "attenuated", or "padded". A nice feature is a clip light that tells you when the amp is clipping. (Note: for some of us, clipping can be a good thing, especially with tube amps or preamps).
Use the -15db pad if you notice that the peak/mute LED comes on regularly.

At the end of the day, use your ears and pick the one that sounds the best to you.

The head is actually rated for a MINIMUM of 4 ohms, meaning you can run an 8 ohm cab, two 8 ohm cabs, one 4 ohm cab, a 16 ohm cab, two 16 ohm cabs, etc., etc.
The 8 ohm cab will work fine.

The Micro VR and Micro CL have a warranty of 2 years for electronics, effective from the date of purchase. The warranty is non-transferrable. The original receipt / proof of purchase qualifies as the official warranty card.

Pro Series

Having the 2 inputs is more a convenience than a necessity. Some amps have two inputs, one for active the other for passive. Others have a single input with a Gain knob, and some have a padded selector switch. Some even have a combination: input jack with active/passive switch and Gain knob.
These are all different ways of accomplishing the same thing: preventing a high-output active bass from pushing the amp into unwanted distortion/clipping. When set to Active, the signal is reduced, aka "attenuated", or "padded". A nice feature is a clip light that tells you when the amp is clipping. (Note: for some of us, clipping can be a good thing, especially with tube amps or preamps). Use the -15db pad if you notice that the peak/mute LED comes on regularly.

At the end of the day, use your ears and pick the one that sounds the best to you.

No, this is not recommended, as this amp is rated for a minimum of 4 ohms. Running at 2 ohms could overwork your head and lead to premature failure.

Yes. Both power amps of the SVT-4Pro can handle a load down to 2 ohms, so you can run one 4 ohm cabinet from each power amp (recommended), or two 4 ohm cabinets on one power amp. You should NOT, however, run a 2 ohm load from the Mono-bridge output, as that is only rated for a 4 ohm load.

The SVT-7Pro, SVT-3Pro, and SVT-4Pro have a voltage selector on the back near the IEC input. Make sure the switch is in the correct position for your local AC mains voltage before you plug in the AC power cord.

Yes, plugging in to the 'power amp in' jack completely bypasses the preamp circuit.

Actually, the speaker outputs are Combo jacks, meaning you can use either a Speakon cable or a 1/4" cable. Just plug right into the middle of the jack.

The SVT-7Pro, SVT-3Pro, and SVT-4Pro have a warranty of 5 years for electronics and 90 days for tubes, effective from the date of purchase. The warranty is non-transferrable. The original receipt / proof of purchase qualifies as the official warranty card.

For EFFECTS BYPASS, you can use a single-button latching footswitch like the AFP-1. For GRAPHIC EQ/MUTE, you can use a twobutton latching footswitch, like our very own AFP-2. OR you can use the AFP-3 (3-button latching footswitch) to control EFFECTS, EQ, and MUTE!

The SVT-4Pro is rear and side vented, you should try to have good air flow. A normal rack will be sufficient for most applications (unless you're playing an outdoor gig in direct sunlight in the desert outside of Phoenix in the summer). Here are a few things to try if you have concerns about your amp overheating.

    1. Add a small clip-on fan to facilitate air flow.
    2. Make sure the vents on the rear are clear from obstruction.
    3. Since power tools are fun, drill holes in the side of your rack case (Important note: REMOVE YOUR AMP FROM THE RACK BEFORE DRILLING!)
    4. Use a shock-mount rack case. These have quite a bit more room around your gear.
    5. Throw away your rack.

    If your head starts to consistently over-heat and shut down, you may need to get some compressed air and blow the dust out of it. If your problem persists, get your amp into an authorized service center.

Running your cabinets this way is not recommended. While technically this would be the way to mono-bridge them, the amp specifically calls for a load of at least 4 ohms in mono-bridged mode. A load of 2 ohms will put more strain on the output section and could eventually (maybe even not-so-eventually) damage the output section. You are better off Bi-amping.

Yes. Since the power amps are separate in Stereo Mode, you can run different cabinet configurations down to 2 ohms per side.

BA Series V2

You would need to use an external step-up or step- down transformer that converts your country's voltage to 120V AC.

The Scrambler is an overdrive effect that allows you to dial in the “Ampeg Grind”. It is based on the classic Ampeg Scrambler pedal. Adjust the 'Drive' knob for the amount of overdriven sound you'd like. Adjust the 'Blend' knob to mix the effected sound with the clean signal.

Having the 2 inputs is more a convenience than a necessity. Some amps have two inputs, one for active the other for passive. Others have a single input with a Gain knob, and some have a padded selector switch. Some even have a combination: input jack with active/passive switch and Gain knob.
These are all different ways of accomplishing the same thing: preventing a high-output active bass from pushing the amp into unwanted distortion/clipping. When set to Active, the signal is reduced, aka "attenuated", or "padded". A nice feature is a clip light or VU meter that tells you when the amp is clipping. (Note: for some of us, clipping can be a good thing, especially with tube amps or preamps).

At the end of the day, use your ears and pick the one that sounds the best to you.

SCR-DI External Power Adapter

The pedal requires a 'minimum' of 100mA which is why it's listed in the power requirements section of the user manual that way. However, the optional 'safety approved' power supply we are able to provide is spec'd at 500mA, either of which is fine but will not matter being above 100mA. This is also why the screen art appears with 500mA to match up with the optional power supplies should they be purchased in the future. for those with One-Spot adaptors or generic or Boss brand DC9V power supplies already on-hand, so long as they are above 100mA (One-Spot adaptors are usually rated around 1500mA)with center pin negative, they will work fine.