My MLTL speakers project with Jordan JX92 was waiting for a final touch with some paint or veneer, but instead it ended up with HiVi Research RT1.3 ribbon tweeters. As good as JX92 are, we all know that there is nothing perfect. It was absurd to think that 4-inch driver is capable of reproducing perfectly the whole range from around 30Hz all the way up to 20kHz. That is why I decided to add ribbon tweeter and improve the high frequencies after I cut the bass port to improve the low frequencies, sacrificing those below 40Hz. The good thing is that I chose project which allows me to add second driver – second generation 35″ MLTL. Although I didn’t use Aurum Cantus G2 as Jim Griffin did, the final result is OK with me for now. The photo below shows the tweeter already mounted in the speaker. Its front panel isn’t the most beautiful but at least it sounds good.
After a long pause it is time for something new in my simple web site. At some point in time I decided to build a pair of good speakers, which will be pleasant for listening and at the same time cheaper than a small car like many of those you can buy in audio store. I chose the notorious JX92s by Jordan. This small driver is widely used in DIY builds as well as in commercial speakers. After half a year of thinking over countless enclosure designs, I ended my search at Jordan’s website and the second generation 35″ MLTL.
The following article is devoted to a HiFi headphone amplifier project of mine based on BurrBrown’s (Texas Instruments company now) integrated circuit TPA6120A . This IC consists of two high power operational amplifiers in one package. Both amplifiers have separate power supply pins, placed symmetrically on both sides of the package so developing a high density PCB will be easy. TPA6120 has impressive parameters, which make it fit the usage mentioned in its datasheet. The main parameters as follows:
- 80 mW into 600 Ω From a ±12V Supply at 0.00014% THD + N
- Current-Feedback Architecture
- Greater than 120 dB of Dynamic Range
- SNR of 120 dB
- Output Voltage Noise of 5 μVrms at Gain = 2 V/V
- Power Supply Range: ±5 V to ±15 V
- 1300 V/μs Slew Rate
- Differential Inputs
- Independent Power Supplies for Low Crosstalk
- Short Circuit and Thermal Protection