Biggest "bang for the buck" audio gear you have owned(in your history)?


This is very subjective, and your opinion on your own systems/items is all that really counts.

From the beginning to now, these would fit that category for me: (in no order)

Original Large Advents
Dahlquist DQ-10
Conrad Johnson ART pre.
Original Monster interconnects and speaker wires.
Nakamichi SR-3a
AR Turntable
ADC XLM II
Audio Research LS-12
Magnepan 1.6
Magnepan 20
Wireworld Gold Eclipse III
Audio Technica Electret Condenser headphones 
Magnum Dynalab Etude and 108 tuners
Magnum Dynalab Receiver (original)
And in those "early days" special pressings and imported Jazz albums. 

There may be others I am forgetting, but these were very good items along my journey. 





jusam
$3 improved the sound more per dollar than any improvement I’ve added. That’s a pretty big bang.

Your right it belongs in the biggest bang for $3 bucks
Back to the beginning...
1-AR turntable
SME 3009 tonearm w Shure V15 Type III
Hafler DH-220
Spica TC-50s
Dynavector 10X5 MKII MC cartridge
Oppo BDP-93 3D Blu-ray Player
Magnepan MG-1.5QR
2-Linn Klassik (office system)
Grado SR 60, 80, 225, 325 (office system)

Conrad Johnson PFR
Stax Lambda headphones


I had already given up on tubes for amplifiers.  The PFR made me open my eyes for solid state in the preamplifier stage. All for the outrageous sum of $850 (used) on ebay.  Incredible bargain IMO.  
AR turntable,Shure V-15,JBL 100s......the place to buy was Crazy Eddie's in Bklyn.NY,his prices were Insane.
Naim Nait 2
Magnum Dynalab Étude
Sota Sapphire

... all bought new over 2 decades ago and still running fine
Nakamichi 410 preamp.

Picked up one used for $90 10 years ago. Worth it for the stepped volume control alone. Still use it foday.
Absolutely, and without a doubt, two pieces come to mind for me. 
- Rogue Cronus Magnum II Integrated Amp
- Audioquest Niagara 1000

Couldn't live without them.
The biggest improvement I made, and not for killer dollars, was when I bought my first pair of serious speakers--Magneplanar MG -I.
1. Vintage tubes. For around $100 each I’m not sure there is a better bang for the buck out there.

2. Empirical Audio Off-Ramp 5.  This USB converter absolutely transformed my digital system for less than $1k used.

3. Audience aR2p power conditioner for $695 new. I’ve since moved on to the TSOX version at considerably more money but the incremental improvement really didn’t justify the cost. The entry level version is a tremendous value.
Thorens TD-160 paired with a Stanton 681EEE cartridge. I paid around $300 total in the mid-70s, best money ever spent for ROI.
After a number of years fiddling with audio I settled on an AR turntable with a Shure v-15 type iii, a Dynaco PAS 3x (bypassed tone controls), a kit-built ST-70 with Mullards, and FMI stand mount speakers (using their own heavy gauge wire). That modestly priced system woke me up!  I had by far the best sounding system in the whole dorm!
Forty years later, I'm blown away daily by a pair of Harbeth P3esr speakers driven by Odyssey electronics and a Hana SL mounted on a Technics SL-1200GR. For my listening habits and room this system is amazing.
Some may blush at the thought of a $10k system being as good as this. I don't obsess about my system at all and just listen to the music.
I downsized my $100k+ all Shindo rig to a pair of Kef LS50 Wireless II with matching KC-62 Sub. I'm not about to say it's better, (it's not) But running Roon directly into them it does blow the doors off most other systems I've heard at similar to double the price. None of which is important, what is important is that I now listen to it daily vs. having to find time to fire up and sit down to listen to the "big rig". Now I can sit and listen, have it in the background, crank it so I can hear it out on the deck, impress the neighbors etc...
Equitech 2RQMade my whole system sound like it was twice as expensive.That, or iFi Zen Blue bluetooth DAC. $129 streaming front end.$129 source connected to $18,000 worth of other components.Sounded pretty dang fine! Lumin U1 mini was big upgrade but cost 16 times as much. Doesn't sound 16 times better. Haha.
Rockwool. About $900. 
Made at least a 30% improvement to sound that I thought was already very good. 
I think the Thorens TD-160 I bought around '75...can't recall the price.  And most recently DQ 10's-$375 and a vintage Proton D540 with the Dynamic Power on Demand feature-$159.  Biggest sounding little amp I've ever heard.
Yamaha NS 1000's
Dayton Wright XG 10 Mk III's
Dayton Wright LCM1's
Threshold 4000
Citation FM Tuner

The Best Values in Audio? The Starke AD4-320 four channel amp and the Magnepan LRS!
Surprised no one mentioned the Advent 300 with the Tom Holman designed preamp section. $279 back in the 70s.  Great foot in the door to high end:  you could add a power amp (I did with a Marantz8) and used it as a preamp. I kept mine for decades, and used the pre or power sections when my primary gear was out for service, or in between upgrades.
Currently, I am blown away by the magnepan LRS.  I have 25k of electronics driving them, but they still amaze me. I feel like I am in no hurry to find my next “forever” speaker, as these make me happy while I look.
So many great bits of hifi, but because I loved them and had them for 20 years my choice is a pair of Royd Doublets bought for AUD$1000 in 1997, finally sold them in 2017 for AUD$450. Thats AUD$27.50 a year, 50 cents a week?
meiatflask,  thank you for the mention of the Advent receiver and Tom Holman.  At that time I worked at an audio shop that was an Advent dealer and I met Mr. Holman at the CES in Chicago.  Later had his APT pre-amp and of course he went on to much success with his THX used in movies/films.  When I met him he was a very genuine and straight forward man.  He and Henry Kloss were the two of many that I met that left lasting impressions.  I did meet Saul Marantz and other, but many were very quiet people....as in, "still waters run deep", Jim Thiel and others. 

1. Lenco L78 turntable.
2. Croft Micro preamplifier/phonostage.
3. Duelund DCA16 bulk wire as speakers cables. 

Cambridge Soundworks Tower 1 speakers (pre Newton) bought in 1998.  Still sound amazing.
A vintage Velodyne 15 servo. which I picked up at a sale from a storage unit facility for $20.   ,Made my day for sure. It even came with the remote. 
Superphon Revelation II Preamp 
Job 225 amp (still in use)
ART DiO dac (modified) collecting dust in basement.
The wonderful thing about stacked/double Advents, was an actual version of what some have called the "Phil Spector wall of sound". 


I'm going to echo a couple of previous posters and say the APT-Holman pre-amp. 
Without doubt, for $2400 I completely transformed my system with Townshend Seismic Podiums under my speakers. The improvement in SQ is more than any component. Followed closely by AGD Audion mono blocks. By far, the best amps I have experienced in 50 years.
Then, for sure, bang for the buck is Silversmith Fidelium speaker cables. At $1200, they can be favorably compared to the $80K ones.
@ tooblue

B&K ST140 power amps....

I knew the B&K guys back in the mid to late 80s, and owned a Discrete Technology LS-2, which was a modified ST-140. I was thrilled to find one of the latest versions of ST140 power amp for $140 recently. Mint shape....added it to my son’s system as a grad school graduation gift. Great amp, great guys. Was sorry to see them pack it in.
 B and K  - Pro10 MC. 
Old pair realistic 12 inch floor speakers, been in garage for 20+ years, dry rot surrounds, but low volume, still sound good.
must be over 30 years old easy!
    Who made the realistic speakers? Mach 1, 2 etc etc. 
they were good speakers, they bested many of the so called upper echelon loudspeakers of the 80s’. 


Ilumnia Magister MK2 speakers ( the best !!!)
VAC phi 300.1
Metronome Technologie C6
Daniel Hertz M6L 
Audio Note CD 2/two
Moon streamer (drive)
Audio Note M6
Ear audio by Paravicini !!!
Wavac M 805
Weiss

Never again:
McIntosh
Musical Fidelity 
Unison research …
Ikea Lack is best deal in audio I know. I have owned five racks, including fairly expensive to me Finite Elemente and SRA. The lack makes high performance shelving accessible for everyone.

Another one is 47 labs OTA cable "kits" with the caveat that need stay under about 2 feet in length to avoid frequency imbalance. For the price, though, their tone is great, they and crush my drawer of high profile branded cables for similar cost.   
This is a great question; one that touches the nostalgia vibe. Not sure this qualifies as best bang for the buck, per se, because, as an impoverished student in 1972, I should have spent this money on my education, instead of my first serious sound system. However, love of music made me do it! So, for me at the time, I guess it was money well spent because this sound system, these components, served me very well for many, many years. The scene of the crime was Tech HiFi in Cambridge, MA. I parted with $350 for a Sansui 2000X and, as best I can recall, around $160 for a Phillips 212 with Shure cartridge. In today dollars, that would be approximately $3,233. I skimped on the speakers, a pair of Studiocraft bookshelves. Can't remember what I paid for those but do remember the entire tab coming to less than $600. A year later, because of the trade-up incentive Tech HiFi offered in those days, I upgraded the Studiocraft with a pair of Ohm C. I upgraded the Sansui (still have it) and the Ohm C in 2001 and the Phillips in 2018. The Ohm C had been re-foamed once and the Philips had a minor repair in the mid 1990's. The Sansui has never been repaired or refurbished but its capacitors & transistors have given their best. How's that for value and solid engineering? Many audiophile friends with systems twice and three times the cost of mine often scratched their heads when visiting, wondering why this system sounded better than theirs. As our parents were fond of saying: "They built 'em good in those days!"
For many years- decades- the biggest bang for the buck was Black Diamond Racing Cones. Now it would be Nobsound springs.  

Only other thing that can touch those was Krissy's Total Contact.
Era/Peachtree D5 bookshelf speakers. Super impressed with these small speakers designed by Michael Kelly. Found a new old stock pair for like $350 bucks. Had Danny Ritchie of GR Research build new crossovers for them. Don’t use them anymore but they’re just too good to get rid of. They’re my biggest bang for the buck though I’ve had much bigger bangs for much bigger bucks.
I had bought Bose 901s in 1972 for $315 ,used then they were fair traded for $575...with out bases....

From above:

"Love to see the large Advent's mentioned.  Mr. Kloss was a pretty smart guy--I mean, he invented the acoustic suspension speaker...where would be be today without that?"

The acoustic suspension speaker was invented by Edgar Vilchur.   

1. Energy 22 Reference Connoisseur loudspeakers that retailed for $2400 USD in 1989 in Teakwood veneer, that I scored for $500 in factory cartons. Still have but replaced them only 14 months ago. Amazing 2-way floorstanding monitors.

2. Full-blown mod of Energy 22’s in 2018 by Agon member, Grannyring. Amazing improvement from top shelf caps, resistors, wires, custom stolen air-core inductors and binding posts.

3. Synergistic Purple fuse in Innuos Zenith Mk 3.

4. Audiocrast Spring pods for under speakers

5. KEF KC62 subwoofer added to Lyngdorf 3400- Audiovector Arrete’-Innuos rig. So amazing. A second one will be installed.

6. Perfect Path Technologies PPT Omega E Mats.
7. Audiovector Freedom Grounding cable.

SonographTT  with Sumiko arm and Talisman S cartridge. $550 1983 Still own TT and arm.

B&K ST 140 with B&K Pro10  $850 1985 sold both in 2011 for $425 (the pair)

BEL 1001 MK5  $1200 2011 Sold it for the same price in 2021.

Magnepan MMG $600 and now the Magnepan LRS + ($1100) If you have enough current and power in your amp. These speakers, decades apart are killer!!!! For the money.

Kingko KA-101 Pro integrated amplifier. Never selling mine. Hard to find as others apparently feel the same way. For both high efficiency speakers and especially headphones.

Kingko KA-101 Pro Tube Integrated Amplifier

I also like the iFi audio Aurora all-in-one system.

iFi audio Aurora