Sumo Nine Plus Amplifiers

4.58/5 (12 Reviews) MSRP : $1200.00


Product Description

650 Watt Push-Pull Power Amplifier (1982-1991)


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Reviews 1 - 5 (12 Reviews Total) | Next 15

User Reviews

Overall Rating:5
Value Rating:5
Submitted by Human2 a AudioPhile

Date Reviewed: January 8, 2016

Bottom Line:   
I cannot recommend this amplifier enough. I had 3 of them including an original prototype. I was also a friend of James so let me share a couple things he said. First off he always claimed the output was 75wpc. Also the opamp in this is a special order higher voltage custom LF353 and not a stock IC. The power supply is rather special and referred to as the cyclotron by my electronics guru. I believe I have had this amp, a silver faced rack-mount model since about 1999. I sold the ugly prototype and standard black model a few years ago and so glad I hung on to this one.
The tweak upgrade IMHO is to replace the opamp with an AD823 which I have done as well as replace the captive refrigerator power cord with an IEC socket. I've also replaced the rca input jacks with Cardas and the speaker binding posts with Eichmanns. In direct comparison this amp made a Krell Integrated amp sound broken. The difference in the mids and highs was stupefying. Adding Hifi Tuning Fuses for the AC and DC rails took this even farther. Quite surprised how loud this drives my 89db Induction Dynamics ID1s but my ears are more sensitive than most; 100db is painful.
The fan is a big issue however and I am about to replace it with a 26dba modern model; fingers crossed. James told me that not a single one of these models ever came back to the factory for warranty repair. It was the lease expensive amp they produced yet the quality is superb.
I actually preferred it compared to the Sumo Gold. It blew away my Andromeda as well which disgraced a Macintosh, Audionics, and Yamaha amps I had. However I also got to compare it to a Sumo The Power which knocked me out of my seat but good luck finding one.
Others are right in recommending a tube preamp to drive this. the combination is staggering if you have the source, speakers, and cables to match. Loves Stealth Audio power cords but I also had wonderful results with DIY DH Labs cord kept as short as possible. The chassis is a bit live and I use some mass loading on top and good cones underneath. Absolutely scary real and completely enveloping sound field which is my thing as I do record a local symphony here. I believe the SRP was only $600 and of course the 650W push-pull description is way way off. Class A all the way!

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Used product for:   More than 1 year

Duration Product Used:   AudioPhile

Product model year:   Pre 1995



Overall Rating:5
Value Rating:5
Submitted by Ken a AudioPhile

Date Reviewed: November 8, 2015

Bottom Line:   
Have owned the Sumo The Nine amplifier for decades. Purchased used at The Listening Room, Westchester Cty, NY. Actually I purchased 2 of them. Has played reliably and beautifully for many, many years. Had it recapped about 15 years ago. Really didn't need the new caps.
Drove Dalquists DQ 10s, Quad 63s, Quad 57s, Sound Dynamics 300ti.
And has been submerged in my flooded basement more than once.
Still playing my 63s as I write this note.

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Used product for:   More than 1 year

Duration Product Used:   AudioPhile

Product model year:   Pre 1995



Overall Rating:4
Value Rating:5
Submitted by Hans Huber a AudioPhile

Date Reviewed: July 2, 2010

Bottom Line:   
I origionally purchased the Sumo Nine in 1984 along with the Sumo Electra preamplifier. I was initially driving a pair of Tannoy Windsors which gave way to a pair of Acoustat 2+2 electrostatic panels which I still have. I still use the Nine and just replaced the preamp with a Blue Circle BC3. The BC3 really works well with the Nine - very musical combo. The BC3 took my system to a new musical level and the Nine shines more. The Nine is very capable and deserves a fine preamp. I also have a sub which you need with panels. The Nine is very easy to listen to hours on end. There are better amps out there but for the money ($1400 new) there is nothing that can touch it. It is a class A design with 65 watts into 8 ohms and 120 into 4. It does run hot and the only drawback is the noisy fan. It is the class A design that makes the sonic differene. Other class A amps have the same beautiful sound as the Nine but cost far more and are somewhat better. The Nine will sound close to a tube amp just not as sweet. I have yet to do any service work on it and have been running it for 26 years. Don't know what I'll do should it ever bite the dust. If you find one, seriously consider it. Anyone can get great music out of $5000.00 amps. You will get close with a used Nine at the fraction of the price (spend the difference on a tube preamp - I should have swapped preamps years ago). The thing to remember is the Nine is only 65 watts into 8 ohms. If you have inefficient speakers, the Nine might not have the omph to drive them if you like loud.

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Used product for:   More than 1 year

Duration Product Used:   AudioPhile

Product model year:   Pre 1995



Overall Rating:5
Value Rating:5
Submitted by roadierider a Audio Enthusiast

Date Reviewed: May 9, 2006

Bottom Line:   
I've been using a SUMO Model Nine amp for my main system for about 4 years now. It is a fabulous sounding little amp! I think solid state "class A" is the way to go if you want a somewhat tube sound without the eventual maintenance issues.

I orig. used a Sumo Andromeda II amp for the mains. Great amp, but overkill on the powerfor my efficient speakers. Now I go thru an active crossover and use the Nine amp down to about 65 HZ . The Andromeda II is now running a homemade NHT driver (#1259?) subwoofer. I quit tinkering after this setup. It sounds great!

FYI, I feed the amps via an AVA "Audio by Van Alstine" hybrid SS/ tube pre amp, then an Audio Control active crossover that I bought about 10 or 12 yrs ago. I think those were the last pieces of gear that I bought new. After that I got addicted to good deals on used vintage stuff.

As far as the fan..... It drove me crazy. I like zero background noise when I 'm listening, so I took the fan and top off and made a new cover. I bought a piece of heavy expanded steel mesh at Lowes. (available in 2 x 2 ft sheets and has 1/2 inch diamond shaped openings). I shaped it perfectly, painted black to match and bolted it on. It looks great and has max open air flow. It gets very hot, but so far it's been fine. The up side with a class A amp is that they make great space heaters in the winter months....:-)

BTW, It's 60 wpc "class A", not 650 wpc, as the above heading states.

Jeff

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Used product for:   More than 1 year

Duration Product Used:   Audio Enthusiast

Product model year:   Pre 1995

Price Paid:    $450.00

Purchased At:   Ebay



Overall Rating:4
Value Rating:4
Submitted by dynalead a AudioPhile

Date Reviewed: March 6, 2005

Bottom Line:   
Bought 2 Sumo Nines when they were first produced (early 80s?). Have been using since then driving Dahlquist DQ10s, Magnapans, and now Sound Dynamics 300ti.
Amps were stored for a time in basement that flooded. Cleaned them up, still operating! Only problem was tendency to blow the power rail fuses.
Fan was noisey. I removed the fan and the case. Amps have been operating like this for years without a problem and no overheating. Keep children and cats away!

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Used product for:   More than 1 year

Duration Product Used:   AudioPhile

Product model year:   Pre 1995

Price Paid:    $1000.00

Purchased At:   The Listening Room




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