Amp Quest - dual mono or mono at a decent price point

[scoran]

Hello,

New member whose poor 2-channel system has been woefully lacking and has finally decided to make amends with his ears. First stop is power amplification. My criteria seem to be at odds with the market (and possibly my wallet), and I could really use some sage advice.

Criteria after lots of homework:

- Solid state
- Mono amp pair (preferred) or possibly dual mono, probably used
- 125W-130W per channel (ideal)
+ happy to look within 100W-150W or lower if really right
+ will also consider lower-wattage Class A under the right conditions
- finesse over muscle
- relatively easy to service by a competent tech
- slight preference for Japanese manufacture
- under $1000

This amp will be the foundation of a modest but thoughtfully-designed 2-channel system. For now this will go in a home office lined with bookshelves and office furniture, but we're planning to move. That said, I don't want more than 150W per channel for this setup. I am fully aware some will see this as a constraint, but my wife and I both prefer more intimate listening to rocking the house.

Here's what I've found interesting so far:

- Harman Kardon HK-775 mono amps
- JVC Victor M-3030
- Pioneer M22
- Denon POA 4400 or POA 6600 mono amps

If any of you have owned or listened to any of these, I'd be interested to hear your thoughts. So far I've only heard the HK-775's and really liked the detail they offered.

What else should I be considering?

Many thanks,
Scott O.

 

[rlisin]

A few you might want to look at: Philips AH 5781, Philips AH 380, INKEL MD2200 / Sherwood S-6040CP. All 100 WPC into 8 ohms. The Philips amps have single transformers, but other than that they are dual mono I think. Also, there are non-dual mono amps that you can get 2 of well within your budget, so maybe consider that. I used sets of 2 stereo power amps as mono blocks in my systems with good results - Philips AH309 in one system, Siemens RE 666 in another system. These are also excellent amps, but lower power (50-60WPC).

Just remembered: there are very good sounding NADs 2100. These have lower power on paper (50WPC), but with 6 dB headroom, which means that in real life condidtions they are as good as most 100+ WPC amps, and they are bridgeable (you can turn each into a 100 WPC mono block).

 

[scoran]

Rlisin, thanks for the recommendations. Philips made good equipment in that era, so if I see either model I'll definitely check it out.

I would not have considered Sherwood, but I like the look of the S-6040CP. Do you know if they made a mono version?

 

[PPstereo]

Your post is an interesting one for the criteria and models put forward. Quite the unique bunch.

What speakers will you be driving with the destined amp?

First off, just my and many others opinion I imagine... Theres really no need for even thinking about differences in 100-150 watt class AB amps. For most designs in this range the difference would be inaudible for all practical reasoning. And you specifically state nothing over 150. Thats all good and well, just I assume you know inadequate power kills speakers not too much in practical use (not saying 500+ watts here LOL). I assume this pertains to your remark about listening for detail not volume.

For what its worth... In my years of playing with allot of gear, speakers and volume levels, WITHIN REASON the more the merrier. It was kind of funny as recently I was going through allot of my excess receivers and testing them through some small 3 way speakers. These little speakers probably had a 20 watt RMS max rating. After listening to these speakers with many 10-100+ watt receivers I got around to hooking up my dynaco 416 power amp. Clearly not in the same realm for many reasons. Well I was floored what a difference it made in the sound/quality at all listening levels. That said I also heard why folks love the cap coupled little HK 330B receiver. Many of those old school cap coupled design units have a lovable tube like charm to them IMO. Quite honestly you might like them too.

Anyway unless your comparing all class A amps like that Pioneer you listed, the wattage difference in such class AB amps within 50 watts (once past 100) is not even worth considering IN GENERAL. That said you have 4 amps, of which only 2 are of similar design. The HK and Denon. The JVC Id never seen for ages if ever. Neat design with its transformer coupled output. And the class A pioneer. Also the mono / dual mono design is cool but not really needed for good build and sound. A power supply is either well engineered / ample or not so much so.

Personally tho hearing your likes and desires Id highly recommend the HK citation 19 or 16. IMO the only downfall of these amps is their looks. But beauty is in the eye of the beholder. They both sound amazing and are VERY well made (dual mono designs. And OMG it doesnt get much easier to work on these. Also they can be bought for reasonable money with room for rebuild work. Right now I saw a few 19s on the bay for decent money overall. The 16s go for more and hearing what I have from you prob wouldnt be necessary for the added cost and size. American made which is a plus in my book.

Overall from what Ive heard first hand and read, much of the HK power amps from the 70s into the early 90s are sought after for a reason. Allot of design, build, country of manufacture so on between em. But overall many seem to feel they sound good. Those monos you mentioned sure appear nice for all reasons. Pretty straight forward layout inside too. They dont appear very common on the net tho. But quite honestly other than your mentioned denon amps none are very common. Theres allot of denon amps out there on the matter. And if you dig japan made your set. Just Im not sure how easy all are to repair and if they have any leg up on their HK counterparts sound wise.

I know you mention your power requirement but you might like the HK citation 12. Dual mono, no lights, amazing sound by many accounts. Can be found and rebuilt for well under your budget. Id personally love to get my hands on one to hear first hand all the hype. But again, 60 vs 100 watts AB.... not much especially at lower listening.

Again be interesting to know the speakers at hand and listening room size.

All cards on the table overall Im a big power guy when possible. Only because I still like to crank it up time to time when I can. And even at moderately loud levels having an extra 100 or 2 over that initial 100 watts really goes a long way. Especially with bigger speakers. Not to say good sound cant be had with small power. It can. All depends on amp, speaker, listening desires so on. Lots of good options for every ones wants out there....

 

[scoran]

PPstereo thanks for your input and questions.

My current speakers are bookshelves. As mentioned this is for a 2-channel rig in a shared home office, 18 feet x 18 feet. That being said, the largest speakers in our home theater setup are Ascend Acoustics CBM-340s - 2 woofers / 1 tweeter. All of these are efficient designs, so my specs at 150W or less are more than adequate for these needs. I am not a big power guy in terms of amps or speakers. (I would buy a very different amp if I had Magnepans.)

Having grown up with the warm sound of Pioneer solid state Silver-era equipment, I'm partial to "warm" sounding, conservatively-rated equipment which is far more capable better than specs would suggest.

To me it seems there is a wide gulf in 2-channel audio today, with all the original design effort going into high-ticket, high current amplifiers. I was shocked to see PS Audio's latest lineup, where you start at the $449 Sprout and next jump to the $7499 BHK Signature 250. This is an extreme example, but you get the idea.

 

[PPstereo]

Understandable.

And yes the current new "consumer enthusiasts" scene is both depressing and more so imo comical. I cant fault some manufacturers for letting a fool and his money part ways. There also a few trying to make products with more realistic price points. But in general its gone to the birds. But theres allot of reasons for all this happening. Thats for another thread. But yes vintage is the better deal for us working class folks.

Best of luck on your hunt

 

[keilau]

Rlisin, thanks for the recommendations. Philips made good equipment in that era, so if I see either model I'll definitely check it out.

I would not have considered Sherwood, but I like the look of the S-6040CP. Do you know if they made a mono version?

Don't let the Sherwood brand fool you. It is actually a rebrand of the high end INKEL MD2200 from Korea.

The S-6040CP is one of the best sounding power amplifier in the 100W/ch range. The high current design and good dynamic range sets it aside from other commercial Japanese brands. I am biased toward the Hitachi/Toshiba lateral MOSFET power devices for audio amplifier over regular bipolar designs. I have 3 of them for a 5.1 setup.

The basic circuit is from the Hitachi technical note and similar to the Hafler HD-200/220, but with much heavier construction and beefier power supply than the Hafler. It is a dual mono design that weights 31 pound. It is like buying 2 mono's. The best part is that you do not have to spend a fortune for one. You usually do not get this type of amplifier construction and dual mono design until you get the $1K range.

Depending on the age and condition, you may want to consider a re-cap of the power supply section. You will definitely need to if you hear hum from your unit. It is normal for old audio equipment. Make sure that there is no DC offset at the speaker output. If you do, correct it with the trim pot VR101L/R. The MOSFET amp usually runs hotter than other bipolar amplifier. If you feel the cabinet is too hot, check the idle current too. All these process can be found in the service manual.

http://www.hifiengine.com/manual_library/sherwood/s-6040cp.shtml