Head-Fi Amp Guide -- Submissions

[KrooLism]

Originally Posted by Edwood

Pictures of amp:










Amp manufacturer Grace Design
Amp name/model Model 901
In production? (yes/no) Yes
List price (final list price if no longer in production) $1495.00 USD
Current "street" price (used only if no longer in production) $1199.00 - $1395.00 USD
Type of amp (solid state/tube/hybrid) Solid State, Bi-Polar Class A Output, Class B Input
Stock tubes (only if tubed) n/a
Crossfeed? (yes/no, how many levels) No
Other processors? (yes/no, type, details) Built in DAC, Crystal CS43122, 24bit 32k to 96K
Portable? (yes/no) No
Power supply (batteries/AC) AC, Linear Regulated, Toroidal, 115VAC 0.16A, 230VAC 0.08A
Detachable power cord? (only if AC, yes/no) Yes, IEC
Number of headphone jacks 2
Jack output impedance (per jack, if more than one) 1Ohm
Jack output (per jack, if more than one -- include @ #Ohms)
Jack type (mini, 1/4", per jack if more than one) 1/4"
Inputs (line, etc., how many) 40K Ohms balanced XLR, 20K Ohms unbalanced RCA, coaxial SPDIF, optical, and AES3
Other outputs (line, pre-amp, speaker, etc., how many) n/a
Speaker output rating (only if speaker out -- include @ #Ohms) n/a
Possible upgrades/upgrade path (tubes, power supply, electronics, etc.) internal DAC board
Housing material (plastic, steel, aluminum, etc.) Machined Aluminum and Clear coated Front Beze, Powder Coated Folded Steel Chassis
Size (dimensions) 8.5" x 8.5" x 1.7"
Weight 5.8 lbs

Grace Design M902.

Pretty much same specs except:
Digital in also has USB option.
Two headphone jacks and one unbal out at +20db gain.
DAC can sample up to 192khz with S-Lock for low jitter.
Still in production - MSRP is $1695 USD

[amb]

(AMB prototype shown, actual appearances vary depending on case used)

DIY design developed by AMB.
Inquire about having one prebuilt by MisterX or thrice.
Assembled and tested circuit board modules are also available from SFT.

-Amp name/model: β22 ("beta 22")
-In production? Yes
-List price: DIY: varies; Prebuilt: contact builders for pricing info
-Current "street" price: n/a
-Type of amp: Solid state class A, all-discrete fully complementary, JFET input stage, BJT voltage amplification stage, high current MOSFET output stage. All stages dynamically cascoded. 2-channel passive ground, 3-channel active ground or 4-channel fully balanced options.
-Stock tubes: n/a
-Crossfeed: None
-Other processors: None
-Portable? No
-Power supply: Companion σ22 ("sigma 22") all-discrete, complementary dual rail tracking regulated PSU, ±24V to ±30VDC.
-Detachable power cord? Yes
-Number of headphone jacks: 1 or more
-Jack output impedance (per jack, if more than one): < 0.01Ω
-Jack output (per jack, if more than one -- include @ #Ohms) n/a
-Jack type: 1/4" phone (unbalanced) or dual XLR (balanced)
-Inputs: Line in (unbalanced RCA or balanced XLR)
-Other outputs: Speaker output (optional)
-Output power (unbalanced): 18Wrms/ch into 8Ω, 5.6Wrms/ch into 32Ω, 0.75Wrms/ch into 300Ω
-Output power (balanced): >50Wrms/ch into 8Ω
-Possible upgrades/upgrade path: See websites
-Input Sensitivity: n/a
-Maximum Gain: 8 (20.8db) default, can be built to other gain settings
-Input Impedance: 47.6KΩ (depends on volume pot/attenuator used)
-Output Impedance: < 0.01Ω 20Hz - 20KHz
-Total Harmonic Distortion: 0.0010% (RMAA)
-Intermodulation Distortion: 0.0072% (RMAA)
-Frequency Response: 0Hz - 2.5MHz, +0, -3dB
-Slew rate: 198V/µS @ 43Vp-p output, 100KHz square wave
-Rise time: 175nS 10%-90%, 100KHz square wave
-Signal to Noise Ratio: 90dBA (RMAA)
-Stereo Crosstalk: -86dB (RMAA)
-Housing material: Various choices
-Size (dimensions): Various choices
-Weight: n/a

[P A R A D O X]

picture of amp:


www.paradoxaudio.prv.pl

DIY design based on X-cans MF amplifier

Amp manufacturer: Paradox Audio (Poland)
Amp name/model: Standard, SE, Extrema
In production: yes
List price: 150 EUR - 1000 EUR
Type of amp: integrated hybrid headphone amplifier
Crossfeed:
Other processors: no
Portable: no
Power supply: internal (220-240V)
Detachable power cord? yes
Number of headphone jacks: 2
Jack output impedance: 12~600 ohms
Jack output: 1,5 watts
Inputs: 1/2
Other outputs: no/tape loop
Upgrades: STD to SE to Extrema
Housing material: Steel chassis, aluminum front panel and knobs
Size: 325 x 100 x 345 mm (W x H x D)
Weight: 7 kg

[RubberDuk]

Sorry if this is the wrong place, thought this seemed like an appropriate thread..

Would it make sense for someone to compile another list of amp recommendations for some of the most common headphones? There are some usual recommendations that are mentioned in almost every post asking for an amp for a certain headphone. There are also a lot of threads asking for amp suggestions for headphones many here are very familiar with. The list could be something like this:

Headphone

Recommended tube
Amp 1

Recommended SS
Amp2

[fraseyboy]

Originally Posted by RubberDuk

Sorry if this is the wrong place, thought this seemed like an appropriate thread..

Would it make sense for someone to compile another list of amp recommendations for some of the most common headphones? There are some usual recommendations that are mentioned in almost every post asking for an amp for a certain headphone. There are also a lot of threads asking for amp suggestions for headphones many here are very familiar with. The list could be something like this:

Headphone

Recommended tube
Amp 1

Recommended SS
Amp2

Great idea! I was thinking of this the other day. Someone should do it... BUT WHO? O_O

[RubberDuk]

Preferably a seasoned head-fier who'd keep it up-to-date. I almost started doing it, but can't I figure out how it should actually be composed. More on that below.

It should at least include separate categories for SS/Tube/DIY, Sennheiser/Grado/Beyerdynamic/AKG etc. most common headphone brands and so on. It would probably need several tables divided either by amp technology, headphone brand, or some other factor. Get complicated quickly. Especially 'cause you would possibly even have to bundle some individual headphones together (such as Grado SR -series separate from RS). Guess it could be one huge table too, but it would have to be made well to be readable enough.

[speedy.steve]

http://www.china-highend-hifi.com/prod01123412233.htm

Amp manufacturer: China-highend-hifi
Amp name/model: G&W TW-J1
In production: yes
List price: ~£55 or $105 in China, 145 Euro on website
Type of amp: integrated headphone amplifier
Crossfeed:
Other processors: no
Portable: no
Power supply: A/C 230 V ± 10% / 50 Hz, for US version 110V power supply - please ask.
Detachable power cord? yes
Number of headphone jacks: 1
Jack output impedance: 32~600 ohms
Jack output: 2x800mw
Inputs: 1/2
Other outputs: no/tape loop
Upgrades: -
Housing material: Steel chassis, aluminum front panel and knobs
Size: 82×27×115 mm (DxWxH)
Weight: 2.5 kg

[dharma]

LAKE PEOPLE PHONE-AMP G99/2

discrete amplifier design
outputs with relais controlled switch-on delay

Picture of amp: ImageShack - Hosting :: lp992frontjb3.jpg
Amp manufacturer: Lake People electronic GmbH (Willkommen bei Lake People Elektronic GmbH)
Amp name/model: PHONE-AMP G99/2 (STEREO HEADPHONES AMPLIFIER G99/2)
In production?: yes
List price: about 350 euro
Current "street" price (used only if no longer in production): -
Type of amp: solid state
Stock tubes (only if tubed): -
Crossfeed?: no
Other processors?: no
Portable?: no
Power supply: AC
Detachable power cord?: yes
Number of headphone jacks: 2
Jack output impedance: 16-600 Ohm
Jack output:
610mW @600 Ohm, 1100mW @200 Ohm, 900mW @50 Ohm, 420mW @16 Ohm (by data on official website);
653mW @600 Ohm, 864mW @300 Ohm, 900mW @240 Ohm, 980mW @100 Ohm, 1040mW @60 Ohm, 1056mW @40 Ohm, 750mW @32 Ohm, 422mW @16 Ohm, (by data on paper user manual included with shipped amp);
1100mW @600 Ohm, 1300mW @300 Ohm, 1500mW @240 Ohm, 1800mW @100 Ohm, 1100mW @50 Ohm, 850mW @32 Ohm, 630mW @16 Ohm, (by downloadable older? G_99Manual.pdf)
Jack type: 2 x 1/4''
Inputs: 2 x XLR (L/R) female, electronically balanced; unbalanced 2 x Cinch(RCA) with priority
Other outputs: no
Speaker output rating: -
Possible upgrades/upgrade path: ?
Housing material: brushed Stainless Steel
Size (dimensions): 130 x44 x 170 mm (W x H xD)
Weight: ?

more:

Nominal input sensitivity: +6dBu
Max. input: +22dB
Gain: +20
Impedance: 10 kohm
Frequency range: 0-50 kHz (-0,5 dB), 0-150 kHz (-3 dB)
Dynamic range: at 2x600R >116,5/120,5 dB (A-wtd), at 2x100R 112/114,5 dB (A-wtd)
Noise: < -86dBu / -90dBu (A-wtd)
THD+N: < 0,0016 % (1kHz / 2x800mW /100R)
Crosstalk: -103 dB (1kHz) / -93 dB (15 kHz)
volume control: ALPS RK 27 with optimized channel balance