Audio Asylum - Inmate Systems

akltam's 3 way Electronic crossover. System
IP Address: 222.166.160.27	Last Update: August 19, 2009 at 18:40:42
Amplifier:	Tri-Amp with electronic crossover. A DIY mono block with Lundahl interstage to drive the mids. A pair of Papworth M100 to drive the bass. (the Papworth M100 has got a very vintage sound like characteristics which sounds very layback. Since it has got 2 pairs of EL34 per channel, I use this to drive the bass). I have discovered manufacturing faults of the M100. The 2 caps from the second 12AX7 to the 12BH7 use two different specs of capacitors. In theory they should be the same type. Fortunately these caps are still above the required specification. User be aware). Also I feel that the quality of the component used in the M100 is not up to Audiophile standard. The two 0.47uf 630V coupling cap to the EL34 is only those 1 dollar value cap. I am very disappointed indeed about the quality of parts used. I will change these parts later. Also I discovered from the schematics that there are 4 stages where they are all coupled by capacitors. So there are 3 sets of capacitors in this amp. I find this design not my cup of tea. One should not expect to get transparent sound from this amp. For me good enough to drive the bass. For the Treble, using a MOSFET DIY amp.
Preamplifier (or None if Integrated):	Self made - Circuit based on Euridice. 6C45 with Output Transformer. Output transformer is Lundahl LL1654. Mono Block setup with Step Ladder Volume. Active crossover - 2 way active using SRPP circuit, mono block PS design. Design Freq 700 Hz.
Speakers:	Three Ways - DIY Setup 1 - Dyna D21, D54AF, 2xSCAN 8535 Setup 2 - Raven 1, Escotar 560D, bass same as above Setup 3 - Scan 2010, Dyna D76, bass same as above The active cross at 700 Hz and 5500Hz. 24 db Linkwitz Riley slope.
Sources:
CD Player/DAC:	DVD player - Pioneer S6D, (Obsolete soon current using it in the bed room) DVD Player - Onkyo DV-SP1000 purchased in July 2004. Video performance is not acceptable as in 2009 standard. This now my CD and SACD player. DAC kit from David Bathurst. Upsampling with CS8420 and with DF1704 DAC, I/V conversion done passively using a 35 Ohms resistor and then SRPP Tube buffer stage. A Separate Transformer for the CS8420, a transformer for the DF1704 and the crytal Clock and separate transformer for each 1704 DAC. The SRPP stage is also mono block design. (This is now also phasing out from system as the Marantz 8260 with tube output takes over even with CD.) PS3 for general music player and server.
Turntable/Phono Stage:	None.
Other Accessories/Room/Misc.:
Speaker Cables/Interconnects:	Non expensive type normal cables. Also DIYed using Cello cables.
Other (Power Conditioner, Racks etc.):	Isolation transformer for the CD player and Pre-amp and active crossover.
Room Comments/Treatments:	Carpet
Music Preferences and Comments:
Music Used (Genre/Selections):	Classical, Jazz, Easy Listening POP.
System Goals/Comments:	To DIY and tried to achieve Hi-End with Minimal cost. But find that this does not work because the cost to experiment is too high.
System Strengths:	Musical, easy listening without sacrificing the clarity and analytical behaviour. Very Dynamic sound using 3 way electronic crossover.
System Weaknesses:	...
Video/HT System: Integrated
TV/Projector:	Hitachi 32PD5000TA plasma - since May 2004. Sony HS20 projector - since June 2004. OS screens 80inch 16:9. (now obsolete) Panasonic AE3000 using 100 inch OS screen. since April 2009.
Processor/Receiver/Amplifiers:	Onkyo 706 receiver. Since 2009. Driving a pair of external DIY amp with 4 paris of MOSFET per channel (mono block). Also using a QUAD 405 driving the mid channel using one LS3/5a.