AKAI is a Japanese consumer electronics company founded in 1929. Known for quality components and precision engineering, Akai is a name that comes up repeatedly when discussing reel-to-reel tape recorders. Akai recorders were the very top of the domestic tape recorder market in their day and were even used professionally. Today's digital equipment is vastly different from the warm and natural analog sound.

ST-1

The Model ST-1 is a handsomely designed precision sound recorder and reproducer. It employs an advanced four track system, where the width of a tape is divided into four sections for recording, so that the tape may be used more efficiently. The ST-1 operates on two tape speeds, 7 1/2 and 3 3/4 ips. Pre-recorded tapes should not be run on a different tape speed than the one they were recorded with, otherwise the sound may become distorted.

Model 345

The Akai Model 345 is a portable tape recorder with an in-line 4-strack stereo recording system. With an adaptor, reels up to 10 1/2" can be used.

Ampex recorders are well known as some of the best built and highest quality American professional reel tape recorders. The Ampex Electric Company of Redwood City, CA was the premiere manufacturer of tape recording equipment following WWII.  

Model 1260

This magnetic tape recorder was engineered to play at two standard operating speeds, 7 1/2  and 3 3/4 ips. 3 3/4 ips is recommended for voice and other long recordings, while the 7 1/2 is used for music and other high fidelity sounds. It utilizes three separate precision dual-track stacked heads for 4-track playback, recording, and erasing.

Model 1270

This model provides the same operational features as the Model 1260, with the added feature of a self-contained 3-watt stereo amplifier-speaker system. This amplifier-speaker system provides flexibility and utility for stereo monitoring. In place of the output jacks featured on the Model 1260, the Model 1270 provides an additional connection panel containing a left and right channel external amplifier jack and a left and right channel headset jack.

Fine Line F-44 Series

This model is a 4-track stereophonic and monophonic recorder. Rather than being mass-produced, the recorders in this series are individually optimized at every stage of production to allow for maximum performance.

Ampex recorders are well known as some of the best built and highest quality American professional reel tape recorders. The Ampex Electric Company of Redwood City, CA was the premiere manufacturer of tape recording equipment following WWII.

AMPEX 300

Ampex Model 300, the mechanical parts were designed by Harold Lindsay and electronics by Frank Lennert. It used 10.5 inch reels, 1/4-inch tape facing inward, and was a two-speed machine switchable to either 7.5 or 15 ips. Harold designed a new head that, when compared to the one for the 200A, was less expensive, performed better and was more uniform from head to head. The new head made tapes more easily interchangeable from machine to machine than was possible between 200A recorders. The first production Model 300 was shipped in late spring, 1949. A 15/30 ips version, the Model 301, was introduced shortly after that. The 300 transport became the platform for many versions of both audio and instrumentation recorders. Overall about 20,000 of these transports were produced.

Source: www.historyofsoundrecording.com

Model 600

In the mid-50s, Ampex introducted the Model 600, which was the first small portable recorder that was still high quality. Because of their sustained quality and durability, they said their recorders were ideal for professional and non-professional users in custom home installations or studio uses. This model can be operated either horizontally or vertically. It is designed to handle 7" or smaller reels and to operate at a tape speed of 7 1/2" per second.

Model 601

The Ampex Model 601 is a lightweight, portable, magnetic tape recorder designed for professional use. It operates at 117 volts, at 50 or 60 cycles per second. It has a tape speed of 7 1/2 or 3 3/4 ips, and has a full or half track head assembly. It can be operated in either a horizontal or vertical position. The microphone input is conveniently located on the control panel, and accommodates any high impedance microphone.

Model 612

The Ampex Model 612 Tape Phonograph is a tape playback machine which has been especially designed for the stereophonic reproduction of magnetic tapes. This model is also capable of playing back both the conventional half track and full track recorded tapes. It is composed of a tape transport mechanism and an electronic assembly. The transport mechanism handles 7" or smaller reels and operates at a tape speed of 7 1/2" per second. The electronic assembly provides two identical but separate preamplifier channels.

Ampro Corporation was founded by Axel Monson who was born in Sweden in 1883. He coined the name Ampro from Axel Monson Products. In the early to late 1950's Ampro produced a line of consumer reel tape recorders. Because the company originally produced projectors, the tape recorders were advertised as being able to bring a thrilling new dimension to silent 8mm. and 16mm. motion pictures, as one could record their own sounds and commentaries.

Model 730

The Ampro Model 730 combines a tape recorder and playback unit. It magnetically records on 1/4" wide tape. It has a dual track, which allows for double the playing time of one. It has a recording speed of 3 3/4" per second. It allowed the user to make recordings from the microphone, or use the radio phonograph adaptor cord to record radio programs. It functioned on a power supply of 105-120 volts, 60 cycles AC.

MODEL 800

Freq Response 30 to 18 kHz

Signal to Noise 50 db

Speed 3.75 & 7.5 ips

Heads 6 - 3 each direction

Motors 3

Reels up to 7 "

Timing accuracy 0.2%

Weight 41 lbs

Source: http://museumofmagneticsoundrecording.org

Imperial

Crown Imperial tape recorders are made up of two different sections, which are the tape transport and the amplifier.  The tape transport allows for all sizes of reels to be used, up to and below a 10 1/2" reel. It has tape speeds of 15, 7 1/2, and 3 3/4 ips. The amplifier contains the necessary features for powering the erase and record heads of the recorder. All of the mechanical as well as the electrical functions necessary for the tape drive to operate within this unit are self contained.

Prince

The Crown Prince recorder is designed to operate from a 110-120 volt AC, 60 cycle power source. In this unit, dual or full-track recording heads are optional. To select speeds between the unit's 15, 7 1/2, or 3 3/4 ips speeds, the speed shift knob is turned to the desired speed.

The DNEPR is a Russian reel to reel tube tape recorder from the 1950's.

Все магнитофоны «Днепр» — катушечные, ламповые, с питанием от сети переменного тока (кроме «Днепр-8»), работают с магнитной лентой шириной 6,25 мм.

«Днепр-10»

Модель 1958 г., усовершенствованный «Днепр-9» с частотным диапазоном 50…10000 Гц

Магнитофон "Днепр-10" Киевским заводом радиоаппаратуры с 1958 года.. Магнитофон ''Днепр-10'' создан на базе предыдущего магнитофона ''Днепр-9'' и по конструкции и внешнему оформлению практически совпадает с ним. Магнитофон предназначен для записи и прослушивания двухдорожечных фонограмм на скорости протяжки магнитной ленты 19,05 см/сек. Ёмкость катушек с магнитной лентой типа 1 или СН - 350 метров. Время звучания или записи 30 мин. на каждой дорожке. Магнитофон "Днепр-10" имеет ускоренную перемотку магнитной ленты в обе стороны.

Регулировка тембра раздельная на низких частотах. Диапазон записываемых и воспроизводимых звуковых частот на указанных выше типах магнитных лент 50...10000 Гц. Номинальная выходная мощность 2,5, максимальная 6 Вт. Питание от сети 127/220 В. Потребляемая мощность 100 Вт. Габариты магнитофона 510х350х320 мм. Масса 28 кг.

Магнитофон был последним в серии «Днепр» похожим то ли на приемник, то ли на сундук с бабушкиным приданным. Уже трудно найти в конструкции его корпуса какие-то дизайнерские навороты, все предельно лаконично, но еще округло, уже наметилось торжество пластмассы над деревом и железяками. Режим работы управлялся кнопками, взятыми будто с ракетного пульта подводной лодки. А главное техническое новшество магнитофона, в отличие от старшего брата Днепра-9, заключалось в пути магнитной ленты, капиталистическом пути, как у недобитых буржуев- рабочий слой внутрь и возможность переставлять катушки местами. Запись 2-дорожечная. Одна дорожка - половина ширины ленты, стандарт бывший единственным до массового появления стерео записей. 

Именно на Днепрах 5-м,9-м и 10-м сформировалась вся советская бардовская песнь. 

«Днiпро-14»

Это модернизированный «Днiпро-12Н», 1967 г. Предусмотрена возможность наложения записей, введена кнопка «пауза» с возможностью дистанционного управления (в этом магнитофоне она называется «Стоп-миг»), переключатель входов.

Магнитофон "Днiпро-14А" с 1969 года выпускал Киевский завод "Маяк".

Магнитофон "Днiпро-14А" (Днепр-14А) рассчитан на двухдорожечную запись звуковых фонограмм с микрофона, звукоснимателя, приёмника, телевизора, другого магнитофона или радиолинии.

Скорость движения магнитной ленты 9,53 и 4,76 см/сек. Длительность записи с катушками № 15 вмещающих 250 м. магнитной ленты типа 6 на большей скорости 2х44 мин., меньшей 2х88 минут. Номинальная выходная мощность 3 Вт. Диапазон частот воспроизводимых громкоговорителями на большей скорости - 63...10000, меньшей 63...6300 Гц. Напряжение на линейном выходе - 0,25 В. Имеется раздельная регулировка тембров по НЧ и ВЧ. Питание от сети напряжением 127 или 220 вольт. Размеры магнитофона - 620х320х305 мм, вес 25 кг

В магнитофоне имеется шкала расхода магнитной ленты, кнопка наложения записи, дистанционный пуск ЛПМ, переключатель сигналов на запись, кнопка паузы. В ЛПМ установлены 3 двигателя, ведущий типа ЭДГ-2К и два перемоточных ЭДГ-2ПК. Схема магнитофона выполнена на семи лампах включая и оптический индикатор. В АС стоит 2 громкоговорителя 2-ГД-19 спереди и 2 1ГД-19 по бокам.

Series 4

The "Ferrograph" is a versatile magnetic tape recorder. It is a machine of high quality, yet simple to operate. In its time, it was marketed as useful to both those who are technically unskilled as well as to engineers or those who use tape recorders professionally. The tape it uses is 1/4" wide. Model 4A has two tape speeds, 3 3/4 and 7 1/2 ips, while Model 4AH has speeds of 7 1/2 and 15 ips. It features components including an amplifier for magnifying weak microphone signals, a recording head for the conversion of electrical energy into magnetic energy to impress upon the tape, and a playback head for picking up the magnetic impressions made on the tape and converting them back into electrical energy.

Series 6 

The Ferrograph was semi professional machine seen many times in films and used by the BBC. This version of the Series 6 is a half track stereo machine with 8.25 inch reels and using standard 1/4 inch tape. A quarter track version was available. It had three motors, two used for fast forward, rewind and back tension and one, a split phase capacitor induction motor, for the flywheel and capstan. This type of motor is almost immune to small variations in voltage or load and is controlled by the mains frequency after reaching its synchronous speed. Three speeds were provided 7.5, 3.75, and 1.125 inches/second. It was extremely heavy using valve amplification and built on a sturdy frame.

TK 20

The GRUNDIG TK 20 Tape Recorder is simple to operate. It operates on twin tracks at a speed of 3 3/4 ips. This unit allows for reusal of tape through erasing recordings, and the old recording is automatically wiped out with each new one. This tape recorder can be used on 50 or 60 cps AC mains with voltages of 117, 200, 220, and 240. Recordings are played back by first sending the tape back to its original spool, then once the recording is ready to be played back it is heard through the unit's internal loudspeaker.

TK 46

The GRUNDIG TK 46 Tape Recorder is deemed the all purpose stereo tape recorder, rated as one of the outstanding tape recorders in the world in its day. It records and plays back both mono and stereo. It is a four-track recorder and has three tape speeds: 1 7/8, 3 3/4, and 7 1/2 ips. It uses 7 inch reels, and has up to 16 hours of recording and playback time. It features 3 separate heads, to erase, record, and playback or monitor the recording.  It can be used on 50/60 cps with 110-240 volt AC.

TK 200

The GRUNDIG TK 200 Tape Recorder is designed for home and family recordings. It has two speeds, 3 3/4 and 7 1/2 ips.  The system has dual tracks and uses 7" reels. It has a recording and playback capacity of up to 4 hours, with a built in "lock" that minimizes the chance of accidental erasure during a recording. Recordings can be played back through the famous GRUNDIG permanent dynamic hi-fi speaker, or through an external speaker with the use of a connecting jack.

TK 830

The GRUNDIG TK 830 Tape Recorder has two speeds: 3 3/4 and 7 1/2 ips. The faster speed (7 1/2 ips) is designed to be used with the Dynamic Microphone for high quality musical recordings, while the slower speed (3 3/4 ips) is more suited towards recordings that do not need to be of such a high caliber, such as speeches or radio plays. The slower speed allows for an extra hour of recording and playback time, as each one of the dual separate tracks runs for 30 minutes at the faster speed and 60 minutes at the slower speed. This tape recorder is regarded as being suited for setting amateur films to music.

First founded in 1912 as an aircraft company, Heath Company manufactured electronic kits following WWII. The electronic kits included radios, stereos, televisions, amplifiers, and many other products. After being absorbed and bought several times by other companies, the company finally ceased operations in 2012.

Image and more information can be found at www.museumofmagneticsoundrecording.org

KB 100

The magnetic tape recorder KB 100 has been designed to be connected solely to the AC mains and operated on voltages of 110, 127, 155 and 220 volts. It is recommended to switch in the KB 1000 some minutes prior to use to give the tubes sufficient filament power and to permit the oil to distribute uniformly in the bearings. This necessary particularly in the cold season.

KB 100 is also in position to impose additional speech and music on tapes bearing already recordings without erasing them.

A suitable microphone is manufactured by VEB Funkwerk Leipzig.

The Kometa is a Russian tape recorder, and one of the most popular tube tape recorders with the design is taken Grundig.

Комета МГ 201

Катушечный магнитофон "Комета МГ-201" с 1962 года выпускал Новосибирский завод "ТочМаш". Магнитофон является модернизацией предыдущей модели ''Комета''. Параметры и внешний вид магнитофона остались практически такими же как у старой модели. Небольшой модернизации подверглась электрическая схема, коммутация, были уменьшены размеры и вес аппарата. Магнитофон предназначен для двухдорожечной записи и воспроизведения звука, а также различных шумовых эффектов. и рассчитан на использование магнитной лены типа 2 и 6, намотанной на катушках по 250 метров. Скорости: 19,05, 9,53, 4,76 см/сек. Магнитную ленту типа 10 использовать не рекомендуется из-за неприспособленности к ней ЛПМ. Переход с одной дорожки на другую производится перестановкой и переворачиванием катушек с лентой. Выходная мощность усилителя 1,5 Вт. Потребляемая мощность 65 Вт. Габариты модели - 400х350х220 мм, вес 14 кг. Претерпев за годы выпуска три усовершенствования электрической схемы в начале 1968 года магнитофон модернизирован в модель ''Комета МГ-201М''.

«Маг-59»

Катушечный магнитофон "МАГ-59" выпускал Горьковский завод имени Г.И.Петровского с 1959 года. Стационарный односкоростной магнитофон ''МАГ-59'' предназначен для записи и проигрывания двухдорожечных фонограмм. Ёмкость применяемых катушек вмещает 350 метров магнитной ленты типа CH или 1. Скорость ЛПМ - 19,05 см/сек. Есть ускоренная перемотка ленты в обе стороны. В магнитофоне применены раздельные усилители записи и воспроизведения что позволяет прослушивать фонограмму во время записи. Частотный диапазон канала записи - 50...10000 Гц. Номинальная выходная мощность усилителя НЧ - 3 Вт. Потребляемая мощность 300 Вт. Питание магнитофона от сети переменного тока напряжением 110, 127, 220 В. Применено 4 громкоговорителя.

При дистанционном управлении можно на расстоянии включать магнитофон на запись или воспроизведение или останавливать движение ленты. Дистанционное управление позволяет использовать магнитофон в качестве диктофона.

Габариты магнитофона 490х450х260 мм, его вес 38 кг. Схема магнитофона несколько раз модернизировалась и по номиналам деталей и по построению, а сам магнитофон выпускался до начала 1967 года.

Magnecorder Vacuum Tube Reel to Reel Recorders
Magnetic tape recorders of this type started around 1948 and become readily available and were used in studios and radio stations in the early 1950's.

PT6

Magnecord PT6 1/4″ is a full-track tape machine. PT6-A basic recorder in portable carrying case. Includes 15" and 7 1/2 ips capstans and pressure rollers. Oscillator tube. 3 speeds. PT6 recorders also available with 2-speed motor for 3 3/4", 7 1/2" and 15" operation. PT6 recorders have half-track heads.

M-33

The Magnecord M-33 tape recorder is mechanically alike. Model M-33 uses the M-33G amplifier. This recorder is designed to record and play back two tracks of material on standard width recording tape, which doubles the recording and playing time on a reel of tape. Recordings can be made from a radio, television receiver, or phonograph, in addition to those made directly from a microphone. Magnecord M-33 operates on 110-125 volt, 60 cycle AC only.

Model 375

The Masco Model 375 Tape Recorder is designed to magnetically record on a standard 7" reel, .248" width ribbon. The capstan and balanced flywheel provides constant tape speed of 3.75 ips – one hour of playing time to a standard reel. The mechanism is equipped with a fast-forward or fast-rewind speed, requiring 2-1/2 minutes each. A monitor jack is provided for plugging in head phones in listening to a recording. The unit has two input channels – Microphone and Radio-Phono, and two amplifier controls – Volume and Tone.

This recorder will record from microphone, radio or phonograph. Provisions are also made for using a larger external speaker. The internal speaker is automatically disconnected when used with external speaker. Operating power is from 105 to 125 volts, 60 Cycle AC. Manufactured by: Mark Simpson Manufacturing Co., New York

Model 52

Dual speed, Dual track tape recorder Manufacturer: Masco Mark Simpson Company Inc., Long Island (USA). 1953. Two track monaural open reel tape recorder, 3,75 ips or 7,5 ips. Metal case, two-piece carrying case. 16 x 11.5 x 14.5 inch Contains 5 vacuum tubes. Has a very good sound when you play back mono two or one track tapes.

Model SM-310

World's most advanced portable Stereo Tape recorder. Virtually a studio in a suitcase, the Newcomb SM-310 combines all the features wanted by professional in a compact stereo tape recorder. Each channel has two inputs, each input its own control. All pre-amplification needed for recording and playback is built in. A four-digit counter pinpoints tape position. Precious tape is handled with extraordinary gentleness. The SM-310 is a half-track, two channel, two speed machine for either stereo or monophonic recording and playback.

Lugavox 1158

ACEC, Atelier de Construction

Belgium,  1958–1962

Valves / Tubes:  ECC83, ECC83, EL95, EL84, EM71

3 motors, 2 speeds (4.75 and 9.5 cm/s), 3 heads (erase, record and playback). The two reels are stacked on top of each other. Similar to Radiobell model 16-2A.

15.5 kg / 34 lb 2.3 oz

MP 410

From the company that was Sweden's largest manufacturer of electronic equipment in its day, the Luxor MP 410 model is a four-track tape recorder for stereo or mono operation. It operates at three speeds, 1 7/8, 3 3/4, and 7 1/2 ips. This model also features self contained playback speakers within its unit.

Pentron HF-400 tube Reel to Reel.

Made in 1956. Weighs 41 pounds. Manufacturer: Pentron Corporation; Chicago (IL) Called the "Emperor" model. There are 2 speakers in the cabinet and one external speaker. According to the instructions the external speaker was a "tweeter" that only came with the HF-400 model. There are 7 tubes - 6SL7, 12AU7, 6AQ5, 6AQ5, 6V6, 6X5, and 5879. 110-120 Volt. 3 Loudspeakers / Ø 6 inch. Measures approx. 13.25"W x 9"H x 13.25"D

Pentron "Aristocrat" Reel-to-Reel Tape Recorder

Manufacturer: Pentron Corporation; Chicago (IL). 1958 Weighs 38 lb (38 lb 0 oz) / 17.252 kg. 7 Valves / Tubes:  6J7 6SL7GT 12AU7 6AQ5 6AQ5 6X5, 4 Loudspeakers

Pentron Model 9T-3C

Multi-speed Pentron tape recorder with full width heads. Range – 50 to 8000eps at 7-1/2" (1 hour) – 50 to 5000eps at 3-3/4" (2 hours). Interchangeable Heads – single or dual track. Push-button Control for speed change. Amplifier – Auto, equalization at both speeds. Weight – 27 lbs.

Made in Switzerland, beautifully crafted machines.

Information based on www.prestohistory.com

PRESTO Recording Corporation was an important company in the broadcast and recording industry, and most radio stations and networks that made use of disc recorders for delayed broadcast, or air checks, etc., were users of PRESTO EQUIPMENT. All of the major broadcast network headquarters, as well as many recording studios used PRESTO recorders.

During WWII, PRESTO was based in New York City, and was involved in military production, including location/range finding equipment, radar installations, long range navigation. Presto was awarded the Army-Navy E award for its contribution in the war effort.

After the war, PRESTO started developing tape recorders. Since AMPEX was ahead and on its way to developing consumer tape recorders, PRESTO never reached its success. Instead PRESTO focused on developing 3 disc tape recorders for broadcast and professional use.

Presto design never changed much over the years.

You can find the interesting history of Presto recorders by going to www.prestohistory.com

PRESTO 908

PRESTO's last machine that debuted in 1957-8 was the A 908 which was available in Stereo as well as 1/2 track mono. Presto was finished by 1965-ending a long history of recording equipment.

Frank Sinatra famously owned and used PRESTO tape recorders.

More specification can be found at www.historyofrecording.com

Advertisement image and more can be found at www.museumofmagneticsoundrecording.org

Tandberg was an electronics manufacturer located in Oslo, Norway, and New York City, US. The company began in the radio field, but became more widely known for their reel-to-reel tape recorders and televisions. The original company went bankrupt in 1978 after a sharp financial downturn. The following year, the company re-formed whilst their data division was split off as Tandberg Data, including the tape recording division, which reduced its scope to data recording. (https://en.wikipedia.org/wiki/Tandberg)

Tandberg Five Stereo A

The tape recorder with dual channel tape electronics equal in efficiency to the finest amplifier components... the new Tandberg is designed to place the stereo recording and reproduction of tape and disc on the highest possible plane. To 'Record' Stereo Disc on Tape—To Preserve the Original Quality • Stereo Disc Inputs built-in to take the output of any stereo changer or turntable. To Make Live Stereo Professional Recordings • 4-Track Stereo Recording at all three speeds provide maximum versatility and economy To 'Record' Stereo Off the Air from Any Broadcast Source • Four 'Record' Inputs meet every recording requirement, including the mixing of any inputs. To Playback Stereo with a Quality That Meets the Test of the Most Critical   Ear • Two Amplifiers Built-in for portable stereo—plus two cathode follower outputs for tape deck stereo. To Be Completely Versatile in Operation • Exclusive Tandberg 4-Track Design sets a new standard in professional record/playback   quality. To Provide Top Performance and Unprecedented Tape Economy • Slow-Speed Quality cuts tape costs 75%. • Exclusive Tape Motion provides professional performance at 1 7/8 i.p.s. and 3 3/4 i.p.s.

Tandberg 74 Stereo Tape Deck (1964-65)

The Tandberg model 74 is a complete quarter-track, three speed stereo, record, and playback unit with two heads. The model 74B is similar to the model 74, but is furnished with a playback pre-amplifier output stage, for each channel, in addition to the combined record/ power output amplifier, and a center channel output. Track system: 4-track, 2-channel, stereo/monaural system Heads: 1 x combined record/playback, 1 x erase Motor: four-pole asynchronous Reel size: up to 7-inch reel Equalization: NAB Tape speeds: 1 7⁄8, 3 3⁄4, 7 1⁄2 ips Valve complement: 1 x ECC82, 2 x ECC83, 2 x ECL86, 2 x EAM86 Dimensions: 15-3/8 x 11-13/16 x 5-7/8 inches Weight: 27.6lbs Finish: teak cabinet Year: 1964

Tape recorder Model 70-C

Manufactured by Premier Electronic Laboratories, NY

A complete high-fidelity professional tape recorder with 3 motors. Three separate heads which is a must in a professional recorder, allows one to monitor the tape while recording without using external amplifiers.

Dual track, will play 6 hours at 3 3/4 ips. Electro dynamic brake action and tape tension, never requires adjustment. Separate bass and treble controls. A separate switch sets equalization for the selected speed.

Telefunken Model Magnetophon 77 Tape Recorder (1959)

This is a four-tube, four-track, stereo recorder. The Magnetophon 77 was produced from 1959 to 1963. It was, although it's very tiny, rather expensive, so it's not so easy to find today, compared to its monophonic brothers M74, M75 and M76. By the way, the M77 was the first full stereo tape recorder by Telefunken.

Telefunken Model Magnetophon 85 - Two Speed Monophonic Tape Recorder (1959-68) 

The tape recorder Magnetophon 85, produced by Telefunken is a recording and playback machine especially designed for pretentious recordists. The advantages of the Magnetophon 85 regarding sound quality are: a high signal to noise ratio,an extremely low rate of flutter and wow, and a remarkable frequency range on both tape speeds.

Track system: 2-track, single channel, monaural system Tape speeds: 3 3⁄4,  7 1⁄2 ips Valve complement: EF86, ECC83, ECC81, EM71a