80's Technics Integrated Amps

In 1987 the V45A V55A and V65A were introduced ( these all SVI400* current drive setup same as the V40/50/60) power output was up over the predecessors as minor refinements were done and larger power transformers were used.

The V85A carried over unchanged

1988 saw radical revision of the V series amp. The SVI4003 and SVI4004 power ic was retrenched in favour of a discrete wheatstone setup, which saw in the SVI320* series power IC rolled out. The all new lineup was the V450 V550 and V650.

Of interest here is where cutting costs on heatsinks become a fork in the road.
The V660 running a SVI3205 could happily supply 2x 140W into 4 ohm, where in the later V78/V98(Z780/Z980 all used the same SVI3205 which was rated to 110W into 8 ohms only ( one only has to see the heatsink difference in the V660 and a V98 to get this)

Also the V85A was retired and replaced with the again discrete output V90D. The big difference here was Digital Inputs ( fiber optic and coaxial) with an onboard 18 bit D/A converter. Power out was on par with the V85A

The cheaper V78/V98(Z780/Z980 came out mainly bought as part of a system)

1989 saw in revised models V460 V560 and V660 with the V90D unchanged.

1990/91 again small changes with V470 V570 and V670 revision and power supplies being the main changes. (G50 and G70 amps took over from the V78/98)

1992 this daw in the VX series VX500 600 700 and the monster VX820. At this point the SVI series were replaced with those awful BC power modules.

From hereon in it simply got cheaper as the march of the BPC invaded the once serene offerings. Later models like the VX920 and their pre and power combos still carried on till the mid 90s.


So my su_v650 is still a good amp :) . Yeah still run it
 
I got Technics su-7700II few weeks back, not sure where it stands and what are the sound characters, I picked this unit against SU-7, not sure whether I made correct decision??
Cool! The II-version of the 7700 was sold in eastern Asia only.
I cannot compare well since I have never heard either of the mentioned ones, but I suspect that they are more or less up to par against each other. Note that the SU-7 has a midi form factor. Also, material-wise the 7700 II might be a bit more sturdy (front and controls with less plastic).
 
Hi all....newbie here on the forum.I have seen the light and recently purchased some Technics gear in the form of a SU-VX920 coupled with a SL-PS900 and the sounds come out of a pair of NZ made Boland Acoustic BTX180 speakers(beautiful sound) made in the 90s by speaker designer Peter Boland and when the pace or mood changes I swap to a pair of Klipsch RF-82's.
I am super happy with the Technic's gear but just curious as to what experience's or views you people out there have in regard to these Technic models...also why did they make this model with no remote transmitter?where as they had one for the SU-VX620 ?? (only want the volume) cause its nice just to hit the volume when you want, without getting off your butt.....cheers Dave
 
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Hi all....newbie here on the forum.I have seen the light and recently purchased some Technics gear in the form of a SU-VX920 coupled with a SL-PS900 and the sounds come out of a pair of NZ made Boland Acoustic BTX180 speakers(beautiful sound) made in the 90s by speaker designer Peter Boland and when the pace or mood changes I swap to a pair of Klipsch RF-82's.
I am super happy with the Technic's gear but just curious as to what experience's or views you people out there have in regard to these Technic models...also why did they make this model with no remote transmitter?where as they had one for the SU-VX620 ?? (only want the volume) cause its nice just to hit the volume when you want, without getting off your butt.....cheers Dave

Remotes, ah the bane of the vintage gear owner! I love my Denon intergrated amps from the 80's, but am selliing them off because I bought one with a remote!

Enjoy the gear for what it is, Technics made some GREAT stuff, it sounds like you did good.
 
I had a rack around the SU-G50. Overall, a decent system, but a step down from the Kenwood KR-8050 I had before it. All that's left of it is the eq (in the closet) and the SL-BD27 tt, which is in use.
 
Technics su-v85a

I've never owned an integrated amp before, but I purchased this the other day (pic from the web), a Technics su-v85a.

attachment.php


It was mentioned here that these amps use some sort of Wheatstone coupling to speakers.

Would anyone be willing to explain what this means?

Anyone with any experience with this series of integrated from Technics?

This is the original quote....

Originally Posted by SVI2004A
1978-1987
The SU-V series was Technics full sized HiFi line that introduced new class A circuitry in 1978. Their other offering was the SU-Z series (Z1 and Z2) which were not quite as wide. The Later Z series also become full width (43cm).

The first lineup of the V series consisted of V2 V4 V6 and the flagship V8. The V4 also was known as V4A and V4K. The V2 and V4 were both based on STK80*0 output ICs, the V6 and V8 on transistor outputs. All featured the synchro bias outpit stages.

In 79/80 the lineup was the V3 V5 V7 and the flagship V9. All these amplifiers were discrete output, with the V9 using high current outputs. All were new class A with synchro bias.

In 82/83 Technics developed computer drive in their amplifiers where a microprocessor could alter ICQ levels in the output stage calculated by signal and thermal sensing, also doubled as a protect circuit for overtemp overcurrent and some cases overinput.

These were released as V303 V505 V707 and the flagship V909 again all were discrete output with the V909 having the same high current outputs.

In 84/85 Technics had simplified the computer drive circuit with the MN1421STA being retired with a MN1404STE appearing in the new lineup except the SE-A3MK2.

Also Heatpipe heatsinks were introduced. The new lineup being V1X V2X V4X V8X. In this lineup the V1X introduced Technics 1st own developed hybrid IC, the SVI2003 which was a 50 watt per channel ic that had synchro bias. The V1X didnt feature computer drive.

The V2X featured computer drive but the chances of getting synchro bias was hit and miss as alot of the earlier V2X amps were fitted with STK2038IV wich had no synchro bias, and others recieved the SVI2003.

The V4X was computer drive and all were synchro bias with the SVI2004A power IC, this amp I consider to have the best sound.

The V6X and V8X were discrete outputs with synchro bias.

In 1986 the V7X and V10X were late additions to the series, both having computer drive discrete outputs with synchro bias.

Also in 86 the V40 V50 and V60 were produced. This phased in class AA amps which have a very different setup with a voltage control amp and current drive amp with a wheatstone coupling to the speakers.

These amps are not featuring synchro bias. V40/50/60 have discrete voltage control amps with SVI400* current drive IC that has the wheatstone resistor bridge inbuilt.

In 1987 the V85A was added class AA discrete output with no synchro bias. The amps from 86 were still in production

All these amps were very well made, all had metal faces. The BPC had not entered the SU-V series. Though it surfaced in the 1986 with the SU-500 and the SA series recievers
 

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The SU-V series was Technics full sized HiFi line that introduced new class A circuitry in 1978. Their other offering was the SU-Z series (Z1 and Z2) which were not quite as wide. The Later Z series also become full width (43cm). The first lineup of the V series consisted of V2 V4 V6 and the flagship V8. The V4 also was known as V4A and V4K. The V2 and V4 were both based on STK80*0 output ICs, the V6 and V8 on transistor outputs. All featured the synchro bias outpit stages. In 79/80 the lineup was the V3 V5 V7 and the flagship V9. All these amplifiers were discrete output, with the V9 using high current outputs. All were new class A with synchro bias. In 82/83 Technics developed computer drive in their amplifiers where a microprocessor could alter ICQ levels in the output stage calculated by signal and thermal sensing, also doubled as a protect circuit for overtemp overcurrent and some cases overinput. These were released as V303 V505 V707 and the flagship V909 again all were discrete output with the V909 having the same high current outputs. In 84/85 Technics had simplified the computer drive circuit with the MN1421STA being retired with a MN1404STE appearing in the new lineup except the SE-A3MK2. Also Heatpipe heatsinks were introduced. The new lineup being V1X V2X V4X V8X. In this lineup the V1X introduced Technics 1st own developed hybrid IC, the SVI2003 which was a 50 watt per channel ic that had synchro bias. The V1X didnt feature computer drive. The V2X featured computer drive, earlier V2X amps were fitted with STK2038IV and others recieved the SVI2003. The V4X was computer drive and all were synchro bias with the SVI2004A power IC, this amp I consider to have the best sound. The V6X and V8X were discrete outputs with synchro bias. In 1986 the V7X and V10X were late additions to the series, both having computer drive discrete outputs with synchro bias. Also in 86 the V40 V50 and V60 were produced. This phased in class AA amps which have a very different setup with a voltage control amp and current drive amp with a wheatstone coupling to the speakers. These amps are not featuring synchro bias. V40/50/60 have discrete voltage control amps with SVI400* current drive IC that has the wheatstone resistor bridge inbuilt. In 1987 the V85A was added class AA discrete output with no synchro bias. The amps from 86 were still in production

All these amps were very well made, all had metal faces. The BPC had not entered the SU-V series. Though it surfaced in the 1986 with the SU-500 and the SA series recievers

In 1984 i tried the V505. It was integrated amp of medium power with computer-controlled 'auto protect' circuit. The quality of the sound was there, but would not allow very much volume before it shut itself off. I was running with a pair of Cerwin Vega D7E (European model), so efficiency didn't suck. I don't know if a problem existed, or if I was just pushing it too much. I soon upgraded to a Hafler pre/power combo DH110 / DH220
 
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The Wheatstone was 4 resistors coupling the voltage amp and the current drive amp to the speaker. The voltage amp would feed the speaker, the current amp would keep voltage drop over it to a minimum. (Current correction)
 
The Wheatstone was 4 resistors coupling the voltage amp and the current drive amp to the speaker. The voltage amp would feed the speaker, the current amp would keep voltage drop over it to a minimum. (Current correction)

Thanks SV :thmbsp:
 
Hi
This is my first post in this forum, i joined since I love my set, which was bought by my father in 1982.
It comprises of SL-DL5, SU-C04, ST-C03, RS-M02. And the speakers were bought later, late 80's early 90's, SB-K915.
I always mantained the equipment cool and clean, but anyhow, as these are Micro-series, heat tends to be a problem. So a couple years ago, one of the main transistors needed replacing.
Even though I love this set, and love the sound it produces, I'm looking at a couple replacements, specifically for the amp, that is the component that gets the more usage these days.
I'm looking at a SU-V95, SU-V5 and SU-V505.
I was wondering which are the pro's and con's of each one, and how they compare between themselves, any help will be really welcome :D
Thanks a lot
Juan
 
The very first integrated amp I owned was a 505. Wow it had a great sound, but had a tendency to go into protection mode at about high noon. I was running them with a pair of Cerwin Vega D 7s.
 
Thanks for the reply!
I already bought the V95, now I'm wondering whether to get the V5 or the V505 (can't get them both! jaja)
Juan
 
Yes! I read that on your first post on this same thread.
Which one would you recommend, taking into account sound quality but also (very important to me) robustness.
Thanks!
 
Both are similar. The V5 might be a little more robust (no computer drive IC which could fail), although it eventually doesn't really matter.
 
Hello!!!
I am a new member and i need your help please,if you could.
So,i have a problem with my dad's sound amplifier (Technics, stereo integrated amplifier SU-X520 D PXS cap) and we need a spare part of heatsink which is BC Power module SVI 3204 A.I can't find this spare part anywhere..
Does anybody know where I could find this heat sink?

Thank you very much for your time... :):)
 
My first integrated amplifier that I used back in college in 1980 was a Technics SU-V2. I sold it a few years later and bought me a NAD 7140 which I used for many years. However, that receiver developed a few issues so I took it out of use and now use a Technics SU-V6 which I found for a great deal on the Bay. In the bedroom I am using a Technics SU-V4. Both of them work great and sound great. Also the SU-V6 looks a lot better than the good old NAD. Finally I have an SU-V75 sitting unused. Just love the look of the "first generation" silver face models.
 
Hello!!!
I am a new member and i need your help please,if you could.
So,i have a problem with my dad's sound amplifier (Technics, stereo integrated amplifier SU-X520 D PXS cap) and we need a spare part of heatsink which is BC Power module SVI 3204 A.I can't find this spare part anywhere..
Does anybody know where I could find this heat sink?

Thank you very much for your time... :):)

SVI3205 or SVI3206 will be better
 
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