I got a steal on this pristine condition ARC SP4 while shopping for a sub $500 option as a backup preamp. Not having experienced any ARC products before, I was completely amazed at the build quality, fit and finish considering that this was a product from the 70s. The preamp is built like a tank and is quite heavy considering how slim and shallow the unit is. The switches, knobs, connectors etc seemed to have this air of precision and finesse. Once I hooked it up the first impressions were definitely positive. The soundstage that this device produced was amazing. Cymbals, guitars and vocals had this separation that was quite captivating. There was this depth in sound which I hadn't experienced before and the bass had this unique feel to it. Am not sure what solid state preamps were popular back in the 70s however, if it sounds so good today, it definitely justified the $1200 price tag back then. There are few things that I would like to point out:
- It might sound much better with amps that have the option to control the sensitivity.
- There are only two non MC/MM inputs that you can use. I find that limiting at times.
- There's no loudness control unlike Macs so listening at low levels might not be possible.
- It's very transparent so your source is going to be critical. The music from my ipod sounds good until I play the same music from my CD player and then I realize the difference.

Although there have been some remarks about the SP4 not being as good as the tube line of ARC, these units are hard to come by and when they do they are gone in a heartbeat. That says a lot...

Exceptionally musical and warm. Excellent imaging/soundstage. Plenty of 'body' in the music - never sounds thin.

Not much, if anything. Perhaps a little on the warm side for those desiring an analytical sound (although I love its warmth) Compared to the SP6E, does not have the level of detail and accuracy. Although soundstage and imaging are first rate, just falls short of the SP6E, which is capable of generating a more substantial 3d image. But then this is to be expected given that the SP6E sold for more than twice its price back in the late '78 - '79 timeframe. One slight annoyance - if using source devices with no variable outputs, the volume control increments are to broadly stepped for my liking. If I would change anything on this preamp, it would be to allow for smaller incremental increases in volume levels. If using a high output source without variable outputs, you have to settle for listening at levels a little too low, but move the volume control one notch, and the DB level becomes a little too high. That said, I dearly love this preamp.

I currently also own an Audio Research SP6E tube preamp, and Carver C-4000t preamp I got this for a steal. First off, the build quality is to be marvelled at. Yes, the SP6E is also built like a tank, but when I removed the cover from the SP4 I was staggered at how good the build quality of this preamp is. In this regard, especially when compared with contemporary preamps, the SP4 demonstrates ARC's obsessive attention to detail and quality. Although not as big as either the SP6E or C4000t, it is very heavy. Although I'm fond of my C-4000t, the build quality of the SP4 leaves it in the dust. Sonically, its interesting to compare the different attributes of these preamps. The SP6E is without doubt sonically superior to both the SP4 and C-4000t. It has a slightly laid back rather neutral character, but it brings out all of the music, accurately, with superior imaging. That said, the SP4 sounds amazingly good. It is more forward than the SP6E, and has a slightly warmer signature. soundstage/imaging is superb, but not quite at the same level as the SP6E (which is one of the very best preamps ever made IMHO). In comparison to the Carver C-4000t, the SP4 is clearly more musical, and just better overall. It must be said that the C-4000t can't be faulted where detail is concerned. But it is far less musically involving than the SP4. The SP4 is so good all round, and its strongest point as far as I'm concerned, is its musically engaging quality. It really is a joy to listen to. Considering just how good this preamp is, I got it for practically nothing. I've heard several other preamps in addition to my own, and the SP4 really shines. In fact I'd hazard a guess that in reference to new products today, it would be difficult indeed to better this preamp's exceptional performance and build quality characteristics.

Similar Products Used:

ARC SP6E, Carver C4000t, Yamaha RX-Z9 flagship processor/receiver. Heard but not owned Sonic Frontiers SF-1

Built like a tank, solid-state so no expensive, hard-to-find tubes to replace, awesome sound experience.

None.

What can I add that others have not said of the fine SP series such as SP-4 and SP-7. The first ARC preamp I heard was in 1973, it was an SP-3 and it made "Goodbye Yellow Brick Road" sound infinitely better than it sounded with my Sansui receiver. Detailed, sweet, warm, punchy and subterranean bass. Sonic bliss that brings a big smile to your face.

Similar Products Used:

None really come close.

Imaging, Dynamics, Style

None noted

Just a plain wonderful preamp. It takes a little getting used to because it will sound better than most anything you have heard. I like this solid state preamp more than most of Audio Researches Tube preamps. It's hard to explain, it just makes the music feel good without dulling it. I am happy I found this one on Ebay. They don't come around often so snatch one up if you can. I have coupled this with both solid state and tube amps and it sounds great with both. I recommend an amp with a big strong transformer to really get the most out of the low end. Both tube and solid state McIntosh amps are the best with this preamp (IMHO).

Similar Products Used:

NAD, McIntosh, Dynaco

gets to the heart of the music, build quality and reliability

none

There’s not much to say, other than accolades and praise.
My SP-4 was built nearly 15 years ago and performs as if it
came out of the box yesterday. It produces a soundfield that will drop your jaw. This is a full feature solid-state preamp, with dual pre-outs, fabulous dual phono inputs, and phono head amp, tuner, dual auxiliary inputs, and dual tape loops with monitoring, and dubbing (yes a balance control too), tone controls, tone defeat, a stereo/mono reverse selector, and a subsonic filter. Proportion, presentation, aesthetics, user-friendly controls and labeling are benchmarks of the entire line of AR preamps, in my humble opinion. I'm not going to mince words here: the AR SP-4 is one the best solid-state preamps I've heard. It's balance of sonic virtues, operating convenience; build quality leaves nothing to be desired.
If you find it on the used market (in good condition) buy it asap. Five stars! ! !

Similar Products Used:

rappaport pre-1, superphon revelation-dual mono, sonyes86b,
carver c-1